Author Archives: surgeryextra

Parathyroid

  • Anatomy
    • Normal: tan-red brown; reticulo-vascular pattern; ovoid
      • 40mg, 4x6mm, ectopic 15-20% time
    • Blood supplied from inferior thyroid artery (arcade from lower to upper cephalad direction)
    • Inf parathyroid
      • within 1cm of where the RLN crosses inferior thyroid artery
      • Assoc with thymus (styloid to aortic arch)
      • 3rd pharyngeal pouch
    • Sup gland
      • post surface of thyroid at upper and middle third of the gland: morgagni’s tubercle, insertion of sup laryngeal nerve: within 1 cm
      • 4th pharyngeal pouch
    • Physiology: Calcium and phosphate regulation
    • PTH
      • Synthesis begins in the endoplasmic reticulum of chief cell
      • PreproPTH to ProPTH to  1-84 PTH: H3N and COO terminals
      • Excreted by kidneys: implications for accurate measurement of pth
      • Half-life= 3.5 min
  • Normal parathyroid gland turns bad by
    • RB(p53) turns into Monoclonal carcinoma
    • Men1 (MEN1 mutated in 20% of cases) /PRAD1 turns into Monoclonal adenoma (benign hyperactive)
    • low ca, low vitd, high po4, vdr alleles genetics, reduced expression of casr, vdr turns into Polyclonal hyperplasia, monoclonal or oligoclonal hyperplasia, monoclonal adenoma
  • Hypercalcemia
    • In gen population is mc d/t hyperparathyroid
    • In hospitalized is mc d/t malignancy
    • Alternative causes: lithium tx, thiazide diuretics, sarcoidosis, pagets, milk alkali, MEN1, MEN2a
    • Hypercalcemia Ddx
      • Cancer
      • Hyperparathyroidism
      • Immobility
      • Paget’s disease
      • Endocrine: thyrotoxicosis, hypoadrenalism, acromegaly, pheochromocytoma
      • Pharm: thiazide diuretics, lithium, tamoxifen
      • Granulomatous disease: sarcoid, tb, histoplasmosis
      • Millk Alkali, Vit D and A excess
      • Benign familial hypocalcuric hyper calcemia
        • Low grade hypercalcemia, eval with 24 hour urine calcium
    • Diagnosis
      • Hypercalcemia and inappropriately high intact PTH (1-84)
      • If low pth consider PTHrp
    • Other useful data
      • Elevated or normal 24 hour urine Ca
      • Low serum po4
      • Increase in serum cl- (cl-::Po4 >33)
      • Increased serum alk phos
      • Bone densitometry
    • Hypercalcemic crisis
      • Ca >13.5 mg/dl (parathyroid carcinoma)
      • Sx: mental confusion, dehydration, abd pain, vomiting, arrhythmia
      • Tx principles: resuscitate and re-expand vasc space, lower blood calcium level, rarely urgent parathyroidectomy (if hypercalcemia is PTH driven)
        • Hours: normal saline, loop diuretics
        • 1-2 Days: Bisphosphonates, etidronate (first generation) Pamidronate (second generation), Calcitonin
    • Calciphylaxis: ischemia 2’ to calcium deposition in the end arterioles
      • Fatal if on trunk
      • 2’ and 3’ hyperpth
      • dx with punch bx shows onion skinning
      • tx/tx parathyroid and skin graft
  • Hyperparathyroidism
    • Primary: disease due to one or more hyper functioning parathyroid glands
      • 80% adenoma 15 % hyperplasia:
        • adenoma is neoplasm
          • 88% d/t single adenoma (size determines): double adenoma 10%
        • hyperplasia: all parathyroid cells abnormal
      • Elevated PTH and calcium levels
      • Incidence .25-1/1000: F(mc post menopausal)>M
        • 2.3% in women 55-75yrs: 1/3 normocalcemic
        • 0.8% in men 55-75yrs
      • RF: radiation therapy, thyroid CA, breast ca 15x higher risk of hyperpth
        • Mutated PRAD protooncogene
      • Sx: stones, groans, abdominal moans, psychic overtones; fatigue, exhaustion, musc weakness, fatigue constipation, weakness, polydipsia, polyuria, nocturia, bone pain, constipation, depression, memory loss, joint pain, loss of appetite, nausea, heartburn, pruritus
      • Assoc Conditions: nephrolithiasis, nephrocalcinosis, hematuria, bone fracture, gout, pseudogout, joint swelling, osteopenia, osteitis fibrosis cystica, weight loss, duodenal ulcer, gastric ulcer, pancreatitis, htn
      • Dx: hypercalcemia (>10.3) with inappropriately high serum pth levels in the setting of normal renal function: not necessarily out of nml range
        • Check: Ca, pth, 24 hr urine excretion (familial hypocalcuric hypercalcemia)
        • Cr clearance
        • Alk phos: bone derived, mildly elevated
        • PO4: depressed
        • Hypochloremic metabolic acidosis: Cl > Po4 = 33:1
    • Secondary: factors other than primary parathyroid disease cause overproduction of pth (renal failure): pth works so hard to keep calcium up because of renal failure
      • Chronic renal failure
      • Vit d deficiency
      • Elevated PTH levels, low or normal calcium
      • Slight advantage to total with autotransplant preferably to upper extremity
    • Tertiary: autonomous
      • Arises from longstanding secondary HPT leading to autonomous hypersecretion of PTH
      • Elevated pth and calcium
    • Localizing Tests
      • Diagnose first: biochemical: high Ca, high/normal PTH
        • Dx is an indication for surgery: benefit from intervention
        • No need for further localization in 2’ or 3’ or familial
      • Ultrasound
        • Quick, convenient, relatively inexpensive, permits FNA of concomitant thyroid pathology, accuracy 60-80% (highly operator dependent). Anatomic information (parathyroid location/thyroid disease)
      • Sestamibi with SPECT
        • (originally used for muga scan-cadiolight, held by mitochondria)
        • 88%sn; Accuracy 60-80%: less accurate (0-38%) for multigland disease
        • Permits assessment of ectopic/mediastinal glands
        • Time-consuming
        • Expensive
        • Wide range of quality
        • Allows unilateral exploration
      • CT: 50-60% sensitive
      • Other localizing studies: Typically reserved for re-operative cases:
        • Mri
        • Venous Sampling
        • Arteriography
        • Four gland exploration 96% sensitive
    • Surgical Indications in asymptomatic patients
      • Age <50
      • Serum Ca >1mg/dL above normal or 11.2 mg/dl
      • Creatinine clearance decreased by 30% now <60ml/min
      • Bone density: t-score >2.5sd: now and/or previous fragility fracture
      • Hypercalcuria >400mg
      • Mayo: asymptomatic hyperpth: 142pt with mild elevated Ca no overt renal/bone disease
        • ¼ of these pt had parathyroidectomy ultimately
        • 1/3 lost to follow up
        • 10% renal fxn decreased
  • Parathyroidectomy-terms
    • Parathyroidectomy : Four gland b/l exploration
      • 4 big, 3.5 gland resection with autotransplantation
        • unilat 96% effective (4% double): would still do b/l
      • Focused v b/l exploration: Why focused parathyroidectomy
        • Doesn’t disturb normally functioning parathyroid glands
        • Decreased early hypocalcemia
        • Facilitates use of local anesthesia
        • Smaller incisions
        • Shorter operating times
        • Long term cure rate 97%
    • Minimally invasive parathyroid (MIP) or Minimally invasive radioguided parathyroidectomy (MIRP)
      • Prelocalization: sestimebe
        • Alike sln: utilize gamma probe
        • Ex vivo: >20% of background
          • ex/ 40 count on background of 200
      • Monitored anesthesia care of awake patient
      • Surgeon-administered cervical block
      • Open 2.5-3.5cm incision or 1cm incision over hot gland
      • Intraop intact pth measurement
        • To confirm that all hypersecreting parathyroid tissue has been excised
        • To prevent overlooking multiglandular disease
        • By providing point of care information postoperative eucalcemia can be reliably predicted during surgery
        • Draw from IJ through neck
        • must drop by 50% in 10min; if still out of normal range must explore other side.
      • Can allow same day discharge
        • If pth falls local and day op is fine, if not, to sleep and explore
      • Conversion to general anesthesia occasionally needed
    • Endoscopic parathyroidectomy
    • Subtotal parathyroidectomy (2/4, 3/4, 3.5/4)
  • Surgery:  B/l neck exploration: Systematic search for all parathyroid tissue
    • Superior Parathyroid glands:
      • Dorsal on thyroid
      • Posterolateral to RLN; above intersection of inf thyroid artery and nerve 80%
        • 12% more cranial, assoc with fat, rarely intrathyroidal
      • If missing superior gland: mc in tracheoesophageal groove of posterior superior mediastinum
        • Re-explore the retro-esophageal space as far down into the mediastinum as possible
        • Explore the superior thyroid pedicle
        • Explore carotid sheath
        • Ligate/mobilize the superior pole of thyroid lobe
        • Palpate thyroid lobe: consider thyroid lobectomy
        • Consider sup thymecotmy
        • Don’t do sternotomy first go round: close and eval in the am: possibly infarcted
    • Inferior Parathyroid:
      • Anteromed to rln
      • If missing inferior parathyroid gland: more variable; key is thymus; cranial horn of the thyrothymic ligament best place to look 44%, 26% within thymic tissue, intra thyroidal 17%
        • 1st Mobilize thymus, pull up into neck, check esophageal tracheal grove, posterotracheal, explore superior mediastinum
        • Can explore carotid sheath to angel of mandible: almost never lateral to carotid sheath
        • Palpate thyroid lobe, carefully inspect thyroid capsule- consider thyroid lobectomy (reasonable), can check intraop u/s
      • If not able to locate missing gland: CLOSE (do everything you can in the neck)
        • Do not perform median sternotomy
        • Confirm diagnosis: repeat labs
        • Repeat localizing studies
        • Role of cross-sectional imagine (4dct) and selective venous sampling
        • Don’t remove normal glands
    • NIM: nerve monitoring
      • Overall risk: 15% neuropraxia, 9% permanent after re-op
      • Helpful in redo
      • 1st time no survival benefit
    • Intraop PTH: no benefit 1st time surgery: success <50% of highest value or within normal range
      • Miami protocol: 4 blood draws: pre incision, pre excision, 5min after excision and 10 min after excision
    • Redo: 85-90% “ectopic” within normal locations
      • If not within first 2 weeks, then wait 6-8 wks
      • Can approach lateral from sternohyoid dissection
      • Always start with neck reexploration
      • MC true ectopic: ant sup mediastinum: lower gland in the thymus.
  • Familial Hyperparathyroidism
    • r/o pheo in men2
      • genetic testing widely available
    • obtain longest duration of eucalcemia
    • minimize risk of surgically-induced hypoparathyroidism
    • facilitate future surgery for recurrent disease
    • Surgical options
      • Total parathyroidectomy with autotransplantation
        • In arm: if recurrent can re explore under local and can cuff test the efficacy
      • Subtotal parathyroidectomy
        • Use of intraoperative pth (more stringent criteria >80% drop)
        • Cryopreservation remainder
  • Multiglandular disease tx
    • Subtotal parathyroidectomy
    • Total parathyroidectomy with autotransplant
  • Parathyroid carcinoma
    • Grey white/translucent and don’t shell out
    • p/w high high ca level (15), palpable mass in neck
    • Dx clinical or local invasion
    • Tx/ hemi thyroidectomy, or en bloc soft tissue resection and lymphadenectomy with ipsilateral thyroidectomy
      • Postop rad dec local recurrence, no chemo

Bariatrics

  • Candidates
    • BMI >35kg/m2 with comorbidity or body weight >80lbs above ideal body weight with co-morbidity
      • Co-morbidities: Htn, cardiovascular dysfunction, hlp, DM II, respiratory insufficiency, stress incontinence, gerd, carcinomas
    • BMI >40 or body weight >100lb above ideal body weight
    • Mortality 3x normal weight parallel
    • Considering BMI 30 with diabetes
  • Procedures: Restrictive, malabsorpitive, or a combination
  • Sleeve gastrectomy: ~40 fr bougie
    • Works by restriction and by rapid transit causing satiety
    • 75% resection of stomach: no bypass
      • Greater curvature of stomach is devascularized prior to resection
    • 60%excess wt loss at 3 years
    • Complications
      • Gastric Leak: most frequent complication 0.9%
      • Stricture, bleeding, PE, delayed gastric emptying, abscess, ssi, splenic injury trocar hernia
    • Revision rates 4%
  • Adjustable gastric banding
    • Silicone band around proximal stomach: dissection through fatty tissue posterior to GE Jxn and creation of a tunnel for the band
      • Pars Flaccida technique: reduces slippage to < 3%
      • Small proximal pouch
    • Fill band with fluid after 6wks
    • Outpt procedure but more f/u needed
    • Gradual lower weight loss: steady weight loss
    • A/e
      • Complication rate <1%, mortality < 0.1%
        • 30% long term reop
        • 20% failure rate
      • Slippage: obstruction, vomiting, epigastric pain
        • Can necrose fundus
      • Dilation of esophagus: >5cm need to empty band
      • Follow pt with barium swallow
      • Erosion: avoid nsaids
      • Perforation: often missed/late presentation
  • RYGB: Gastric Bypass
    • Restrictive and malabsorptive
    • 60ml proximal gastric pouch anastomosed to Roux limb, created 150cm from the ligament of treitz
      • Rou-ex-Y limb anastomosed to stomach pouch
      • 75-150cm alimentary limb
      • 50-100cm afferent limb
      • 10-15mm stoma not reinforced
      • No fundus included in pouch: important for outcomes (hormonal)
    • Hormonal changes in ghrelin, glucagon-like peptide-1, and peptide YY that influence eating behaviors and body weight.
    • Reduced bile and lipolytic enzyme secretion 2’ no duodenal activation
      • Delayed fat breakdown and micelle formation limits absorption. Can cx steatorrhea
    • Advantage
      • Mean EWL excess wt loss 60% at 12 mo
      • 80% at 24 mo
      • 75% at 30 months
      • Low failure rate
    • A/E
      • Operative 30 d mortality 0.1-0.5%
      • MC complication: dehydration
      • Malabsorption: difficult to reverse
        • Protein intolerance
        • Divalent cations: (absorbed in duodenum): iron calcium magnesium
        • Oral FeSO4 supplements decreases absorption of Ca, Mg, Zn
        • b12 (stomach antrum-intrinsic factor)
        • Supplementation necessary: Vit B, Ca, Vit D, Folate, Thiamine
        • Vit B deficiency: occurs > 1 year after operation
        • Macrocytic anemia and neuropathy
        • Vit D deficiency: fat sol vit: Loss of fat absorption dec vit d, higher bone turnover and dec bone mass
        • Follow pth, vit d, and ca levels
        • High PTH means low ca or vit d
        • Supplement with ergocalciferol
      • Leak 1-2%, revision 4-8%
      • Complications 2-5%
      • Death 0.5-1%
  • Biliopancreatic diversion
    • Greatest weight loss and most nutritional problems
    • 75% of stomach resected and bypass all but 250cm of small bowel
    •  Procedure
      • Sleeve gastrectomy: 60Fr bougie
      • Duodenum is divided 2 cm distal to the pylorus, preserving the blood supply and vagal innervation of the antrum.
      • A Roux limb is created by dividing the small intestine 250 cm proximal to the ileocecal valve and anastomosing this to the postpyloric duodenal cuff.
      • The bypassed biliopancreatic limb is sewn to the Roux limb 100 cm proximal to the ileocecal valve, creating the “common channel.”
    • Vs RYGB
      • More technically challenging
      • Large gastric capacity
      • less dumping syndrome
      • more effective in reversing DM, HLP, HTN in super obese bmi>50
      • >wt loss at 3 years in super obese
    • Not strictly malabsorptive
    • Hormone changes: specifically gastric bypass and sleeve gastrectomy
      • Induce satiety: L cells of lower gut: Increases in GLP-1 and PYY
      • GLP-1 released hindgut in increased amounts potent release of beta cell insulin release
      • Decrease in Ghrelin: proximal stomach and fundus
      • Normally: Arexogenic: induces hunger
      • Proximal small bowel will make up for some of the ghrelin
    • Mean excess weight loss after BPD > 70% in published series.
    • 30d operative mortality 0.5-1.1%
  • Jejunoileal bypass: not done
    • a/e bypass segment bacterial overgrowth and protein malabsorption leads to cirrhosis
  • Outcomes
    • Resolution of co-morbidities
    • DM 76% resolved
    • 2’ to calorie restriction (some part form glp-1)
    • Rapid wt loss 1lb/d.
    • Improved sensitivity to insulin
    • HLP 70% improved
    • Htn 61% resolve
    • Sleep apnea 85% resolved
  • Operative mortality <30d:
    • restrictive 0.1%
    • bypass 0.5%
    • biliopancreatic diversion 1.1%
  • General Rules
    • Postop: Can never smoke or take NSAIDS
    • Not normal to vomit after gastric bypass
    • Don’t give dextrose, give ns and thiamine
  • Early Complications
    • Pulmonary: apneic arrest, dvt/pe
      • Apneic Arrest- anesthetic in fat
      • Hypoventilation leading to resp/cardiac arrest
      • Incidence <2%
      • Prevention is key
      • Pre-op sleep apnea dx
      • Peri-op cpap: extremely important
      • Admit high risk pt to monitored setting
      • Limit narcotics
      • Signs: desat, somnolence, mental status changes
      • Tx: intubation
    • Dvt/pe
      • Incidence 1-2%, fatal pe 0.2%
      • Risk factor: obesity hypoventilation syndrome
      • BMI >55, male, lower extremity venous ulcer dz
      • No longer consider prophylactic insertion of filter
      • Tx: Heparin, ambulation, scds
      • Symptoms: diaphoresis tachycardia hyopxia
    • Enteric leaks
      • Incidence: 1-8% higher with revision
      • Possible locations
        • gastroJ
        • gastric pouch staple lines
        • remnant gastric staple line
        • J-Jostomy: typically high volume
      • Pt deteriorates rapidly
      • Technical issues
        • Missed perf: blind instrument insertion
        • Avoid devascularlizing the pouch/roux limb
        • Avoid tension
        • Ante colic: make a large groove in omentum
        • Retrocolic less tension
        • Consider longer pouch in super-morbidly obese
        • Test anastomosis
      • Presentation: not with peritonitis, can be insidious
        • Tachycardia: HR >120 (most sensitive)
        • Tachypnea, respiratory distress, hypoxia
        • Elevated wbc
        • Fever >101.5
        • Sever abdominal pain
        • Oliguria
        • Mental status changes
      • Dx
        • UGI series: routine use debatable, doesn’t evaluate anastomosis of gastric remnant or distal
        • CT
        • Exlap
      • Tx
        • Leak control and drainage
        • Supportive care
        • Iv ABx
        • Vent support-early trach
        • Beware decubiti
        • Nutrition: gtube preferred
        • Remnant decompression/enteral feeding
        • TPN
    • Small bowel obstruction
      • Early dx and or exploration to prevent acute gastric REMNANT distention
        • Hemorrhage
        • Early: intraluminal: staple line bleed: 50-70% stop spontaneously
        • Tx IVF and blood product resuscitation
        • a/e intraluminal blood can cause SBO: hemobezoar
      • Late
        • Peptic ulcer dz: bleeding ulcer in remnant
        • Marginal ulcers: 2’ to smoking or nsaid use
        • Dumping syndrome: post RYGBP: up to 70%
          • Early: 15 min pc: d/t sudden osmotic load in jejunum
          • isotonic fluid from plasma enters lumen: falls in BP
          • stimulation of argentaffin cells: release of 5HT: serotonin sy
          • Late phase: 1.5-3hr pc: hypoglycemia
          • High glycemic index food is rapidly absorbed:insulin spike: glucose and K shift intracellular
          • Tx: frequent dry meals, low carb, high protein, fluids between meals only
          • Reinforces correct eating behavior
      • Rhabdomyolysis
        • 2’ muscle compression during surgery (concern >4hrs)
        • Labs: Hyperkalemia, hypocalcemia, hyperphosphatemia, hyperuricemia, acidosis, aki, dic, compartment syndrome
        • Cpk >5x nml, peaks 4-7 d. remains elevated 12 days
        • Urine myoglobin
        • Sx: pain, tenderness, swelling, bruising weakness
          • Dark uring, fever, malaise, confusion
        • Imaging: hyperechoic skeletal muscle on U/s
          • CT: muscle necrosis/ calcification
          • MRI: muscle edema
        • Tx
          • IVF: > 1.5 ml/kg/hr
          • Mannitol
          • Sodium bicarb pos: can accelerate ca/po4 deposits in tissues
          • Don’t correct hypocalcemia
          • Control hyperkalemia
          • HD if necessary
      • Wound infections
        • Adipocyte hypertrophy changes adipose structure and impaires function
        • Inflammatory mediators invade: chronic low grade inflammatory environment with angiogenic inhibitors and fibrosis, tissue becomes hypoxic
        • Impaired collagen synthesis
  • Late complication
    • Anastomotic strictures: within 6 weeks 10% incidence
      • Lower with linear staples
      • Controlled with balloon dilation
      • Marginal ulcers ~6%
      • Epigastric pain, can bleed/perforate
      • Most tx with PPI: may need lifelong
      • If unresolved: r/o gg fistula
    • Nutritional:
      • MC: B12, folate, vit d, calcium, iron, B1, B6, vit A, zinc, selenium, mg, Cu
      • wernicke’s polyneuropathy (acute thiamine deficiency and glucose immediately), malnutrition
    • Cholelithiasis
      • MC during rapid wt loss >1.5kg or % BW /wk
      • Cholesterol supersaturation of bile
      • Increased nucleation
      • Decreased calori intake lowers CCK secretion
      • Obesity related cck resistance
      • Concurrent routine chole controversial: 36% will get stones post RYGB
      • Urso 300mg bid x 6 mo: prevents GS formation
    • Weight regain
      • 2’ pouch dilation or GG fistula
      • MC 2’ to non complicance and poor food choices/portioning
    • SBO: 0.5% incidence
      • Etiology: internal hernias, adhesions, trocar hernias, JJ intussusception, hemobezoar
      • Internal hernias can occur at the jejunojejunostomy defect, Peterson’s space behind the roux limb, or transverse mesocolon defect if retrocolic limb
      • Sx: vague, pain out of proportion. Likely will not have vomiting
      • Gastric remnant blow out is fatal: rapid dx and tx vital
      • CT: can miss/be misread >60% of cases
      • Low threshold for exploration
  •  NB
    • Unemancipated minors can’t consent (technically), need to assent with parental consent
    • Medical tx
      • Orlistat: antiobesity medication: inhibits gastrointestinal lipases and leads to dec fat absorption
      • Sibutramine: oral agent inhibits neurotransmitter reuptake
      • a/e cardiac morbidity

Laparoscopy

  • Benefits: reduced trauma and stress response
    • Closed abdomen may be a factor
  • Physiologic benefits
    • Less impairment of pulm fxn
    • Less blood loss
    • Less immune suppression
    • Less stress response
    • Less adhesions
  • Clinical benefits
    • Less pain: less narcotic use
    • Quicker resumption of diet
    • Shorter LOS
    • Quicker return to work
    • Less incisional hernia
    • better return of normal lung volumes (FVC and FEV1)
  • Entry Techniques: no advantage in preventing major complications
    • Types: Veress Needle, Hasson: Open direct, Optical Viewing Trocars
  • Physiology: Insufflation
    • Insufflation: CO2 gas: 12-15mmHg
      • Gas exchange: CO2 + H20 = H2CO3 = H + HCO3: resp acidosis
      • Asa 1/2: no effect
      • Asa 3/4: increased map and increased svr with decreased CO leads to hypoxia and dec o2 delivery
    • Altered ventilation
      • Increased IAP: like a severe valsalva
      • Decreased FRC: increased alveolar dead space
      • Increased airway pressure
      • Decreased compliance 2′ decreased diaphragm excursion
      • CO2 rapidly absorbed from the peritoneal cavity
        • Causes hypercapnea and respiratory acidosis
      • Requires an inc in minute/tidal volume to keep pco2 acceptable: up to 16% to maintain normocarbia
        • Anesthesiology increases rate to compensate
    • Altered hemodynamics
      • Increase in catecholamines, angiotensin and vasopressin
      • Venous return (ivc) is decreased
        • Decreases stroke volume and thus decreases cardiac index
      • Response is increased SVR: lasts up to 30 min post procedure
        • SVR = ((MAP-VCP)*80) /CO
      • Increased intrathoracic pressure
      • Increased CVP and PCWP
      • Increased PVR
      • Decreased CI: Caused by decreased SV 2’ to IAP compression of IVC causing decreased venous return
        • CI = HR * SV / BSA
      • Reduced CO: bad for: cardiomyopathy, as, etc
      • Response dependent on volume status of pt
        • Typically pt are low or euvolemic
      • Pt Positioning
        • Trendelenburg: enhances altered hemodynamics
        • Reverse trendelenburg: worsens these effects
    • Immune system response
      • White cells still rise
      • Acute phase reactants: CRP
        • Rises 4-12 hours after surgery, peaks 1-3 days, remains elevated for 2 weeks
        • Less rise with laparoscopy: likely secondary to CO2gas (not just incision size)
      • CD3 down reg
      • Activated lymphocytes down reg
      • Cytokines: Less rise of IL 6, TNFalpha, IL1, granulocytes
    • Neuroendocrine response
      • Less elevation of adrenal hormones: cortisol and epinephrine
      • Less elevation of sympathetic hormones: dopa and norepi
      • Less elevation of pituitary hormones: acth, prolactin, growth hormone
      • All have 20-40% lower peaks
      • Faster return to normal 4 v 9 hours
      • Peak glucose increase 25% less
    • Increased intra-abd pressure stretches diaphragm and irritates nerves
      • No increased risk of DVT
    • Altered Renal Blood flow
      • Decreased RBF during tension pneumoperitoneum
      • Increased renal vein pressure
      • Decreased urine output: usually not clinically relevant
      • Increased renal blood flow after exsufflation: usually no effect on serum creatinine
      • Preserve function with pressure <20mmHg
      • Tx: Increase in fluid administration, dopamine
    • Increased ICP
      • Independent of arterial pH, oxygenation and MAP
      • Mechanism not elucidated
      • Usually without clinical consequence
  • Complications
    • Bradyarrythmia on induction of pneumo:
      • 2’ to vagal stimulation induced by peritoneal stretching on insufflation
      • Tx/ immediate cessation of surgical stimulation
        • Deflate abdomen
        • Glycopyrrolate or atropine
    • CO2 embolism
      • CO2 directly into venous channel: obstruction of R ventricular outflow tract
        • Decreased end tidal co2
      • MC during hepatectomy
      • Cyanosis
      • Increased venous pressure
      • Ventricular arrhythmia
      • Tx
        • Stop insufflation
        • Left Lateral Decubitus: head down
        • Hyperventilate
        • Aspirate gas from R atrium through central venous catheter
    • SubQ emphysema during or after laparoscopy
      • Presents as crepitus
      • Frequent occurrence: leak around abd insufflating port
      • Can be assoc with respiratory acidosis
      • Prolonged postop ventilation
      • Will dissolve in 24-72 hours
      • May bruise
    • Shoulder pain: nerve irritaiton
      • Last up to 3 days
    • Aspiration of gastric contents:
      • increased IAP can increase risk of regurg
      • P/w tachycardia immediately following extubation (tx IS and nebs)
    • Injury to viscera: bladder, bowel
      • Bladder
        • Repair primarily
        • Leave foley 7-10 days
      • Enterotomy 1.8%
        • Immediate:
          • Cx/ Trocar, suture passer, adhesiolysis
          • Primary repair
        • Delayed: 20% missed, 8% mortality
          • Cx/ Thermal burn: cautery ultrasonic shears
      • Bleeding
        • From trocar site: figure of 8 suture or hook cautery: don’t ignore
        • From trocar entry:
          • Convert to open, isolate injury primary repair
  • NB for common procedures
    • Chole: Identify the critical window
    • Colon: Right, Left and LAR
      • Risk: bleeding, infection, visceral/ureteral injury, leaks
      • Minimize risk: medial to lateral dissection, proper visualization, proper identification of anatomy
      • Benefit: less pain, fewer wound complications
    • Hernia
      • TEP: total extraperitoneal rpr
      • TAPP: transabdominal pre peritoneal rpr
      • Risk: chronic pain, recurrence
      • Chronic pain: TEP less than open
      • Lap: more expensive, but can catch b/l hernias
      • Higher recurrence (veterans data)
      • Recurrence do opposite of first: lap/open
      • Recurrence after lap inguinal: inadequate dissection, mesh fixation and pt obesity and smoking
  • Future
    • SILS
      • Growth preceeds clinical benefit
      • Increased hernia’s
      • Body image better, Cost higher
    • NOTES: experimental
    • Robotics: level 5 (expert opinion) evidence:
      • better cosmesis
      • Less pain, shorter LOS, less ebl
      • More expensive, longer OR times

Sarcoma

  • Basics
    • Site of Origin
      • 59% Extremity
      • 19% Trunk, ant abd wall (desmoid), flank
      • 15% Retroperitoneum
      • 9% Head and neck
  • Risk Factors
    • Trauma: burn, scar, chronic tissue irritation, chronic lymphedema
    • Genetics
      • Neurofibromatosis: Von Recklinghausen’s Disease
      • Gardner’s Syndrome
      • Tuberous Sclerosis
      • Li-Fraumeni Syndrome
      • Fap- desmoid
    • Radiation: 10 year latency after radiation therapy or exposure
      • Periphery of radiation (bad)
    • Chemical: polyvinyl chloride, burns
    • Lymphedema: Stewart-Treves Syndrome
  • Classification: Based on soft tissue they resemble
  • Presentation: MC painless lump, slow growing
  • Radiologic Eval
    • Plain Xray: location of bone tumor assoc fractures and cortical disruption
    • CT scan abd & pelvis: always use IV contrast
      • CT scan chest: look for mets
      • Pre op cxr v ct: cxr adequate
        • metadata > 1 cm mets matter
    • MRI: if lesion is >4cm
    • Bone Scan: detects mets, eval cortical and intraosseus extent of bone tumors
    • Angiogram if necessary to assess vascular relationship to tumor
  • Staging TGNM
    • Tumor Size
      • T1 <5cm: a superficial to fascia, b invades
      • T2 >5cm
    • Grade: Extent of differentiation mitotic rate, necrosis
    • Path most imp for grade
      • >25 mitosis for 50 high power fields = high grade = radiation tx
      • Subtype not very imp
      • Histo: Most important prognostic factors
        • Low grade: 5-10% metastic
        • Intermed: 25-30% metastatic
        • High Grade: 50-60% metastatic
    • Mets: MC pulm, retroperitoneal spread to liver first
      • Route of tumor dissemination: hematogenous because they are mesenchymal cell origin
      • Extremity and bone tumors usually spread to lung and then bone
      • Abd, pelvic, and retroperitoneal: go to liver and lung
      • Sarcoma rarely met to LN
        • Primitive tumors: small cell, synovial, clear cell, angiosarcoma, rhabdo, epithelioid
        • Chemo sensitive
        • Pos nodes means complete LND
      • Stage 4: mets or nodes
  • Dx: made by biopsy
    • FNA: not very helpful, small cells lots of fibrosis
    • Core Needle Biopsy: ok but need to tract out in line of incision
    • Excisional: tumor <3cm: ok but don’t enucleate
    • Incisional Biopsy: orient biopsy scar with proposed resection lines
      • Most deep, fixed, within musc
      • Exception: DMFB: firm in SubQ
    • Imaging before doesn’t’ change anything unless worry about neurvasc involvement
  • Tx
    • Complete surgical resection including biopsy sites
      • Radical Surgery: improves local control
      • <10% recurrence if: <5cm tumor, superficial, 1 fascial compartment, margin of 2cm
      • DO NOT SHELL OUT: Wide local excision: 2cm margin preferable
        • Muscle group excision
        • Compartmental excision
        • Drain inline with incision
        • Amputation: reserved for recurrences and tumors that render extremity useless
    • Radiation: Intermed to high grade tumor (high grade or low grade >5cm; high mitosis >10)
      • Improves local control: no survival benefit
      • high grade do respond
      • Inadequate margins: limb preserving procedures, close margins around nerves or vasc structures
      • all op area 5000 cgy and tumor bed 6500: external beam = brachytherapy
      • Pre op vs post op:
        • pre less fibrosis and edema worse wound healing
        • post opposite; high grade in sensitive loc do pre
    • Chemo
      • No survival benefit after complete resection
      • Doxorubicin, dacarbazine, ifosfamide (20-50% respond)
      • Postop beneficial with positive margins and high grade histo
      • DTIC clinical trial: adriamycin; Iphosphomide
        • Adriamycin and ifosfamide demonstrate response rates of 20-30%
          • 80% of skeletal sarc will develop recurrence
          • 50% of pt with high grade sts will recur
      • Neoadjuvant best in osteosarc, ewings, rhabdomyosarc
      • Improves limb sparing, improves overall survival
    • Metastatic Dz = metastectomy
      • 44% occur in lungs: f/u with Chest CT
      • Tx: Surgery should be considered even if multiple and bilateral
        • Stapled metastasectomy with minimal lung removed
      • Not an option if:
        • Primary dz not well controlled
        • other systemic sites involved as well
        • recurrent pulm nodules within 1 year of prior lung resection
  • Recurrence
    • RF: >50 yo, >grade 2, retroperitoneal, tumor depth, size >5cm,  pos margins, path: mfh, angiosarc, rhabdomyosarc
    • Up to 50% of retroperitoneal and intra-abdominal sarcomas will recur after initial resection
      • Retroperitoneal Sarcomas: local recurrence, liver and lung mets
    • Extremity sarcomas: pulmonary metastases
    • Aggressive f/u is life prolonging
    • Follow up imaging q 4 mo
      • Sarcomas that recur usually do so within 5 years
    • Poor prognostic features: liposarc >1cm/mo, large >5cm, short disease free interval
    • Slow growing sarcomas with long dz free interval should consider re-resection
      • R0 resection, resect all prior incision, drain and specimen bed sites
    • Consider neoadjuvant chemo/xrt if lesion is large, fast growing, near critical structures or difficult to achieve limb-spaing approach
    • Resection is preferred treatment for recurrences
      • Amputation
      • Pulmonary metastasectomy: up to 40% 5 year survival
    • Chem and radiation generally palliative at best
  • Subtypes
    • MC: malignant fibrous histiocytoma, liposarcoma, leiomyosarcoma
      • MFH: mc soft tissue sarcoma, lower extremities, 20% of all extremity sarcoma
      • Pleomorphic high grade sarc categorized here as well
      • Liposarcoma: 2nd mc sts, usually lower extremities, 25% of extremity sarcomas and 45% retroperitoneal sarcomas
      • Leiomyosarcoma: 20% of retroperitoneal sarcoma
    • Bone sarcomas are classified according to the matrix they produce
      • Osteosarcoma
        • MC bone tumor
        • Usually teenagers (15)/adolescents: male predominate
        • In pt over 40 yo it is usually assoc with pagets dz or prior bone irradiation
          • Chronic remodeling
        • 80-90% occur in metaphysis of long bones:
          • distal femur > proximal tibia > proximal humerus
        • MCsx: painful soft tissue swelling and tenderness
        • Tx: neoadjuvant chemo followed by limb sparing surgery
      • Chondrosarcoma
        • Usually 40-60yo
        • Commonly occur along pelvis, femur and shoulder girdle
        • Rarely responds to chemo (may be considered in young patient with high grade tumor
      • Ewing’s sarcoma
        • Almost always occur around 20yo, Caucasian
        • 90% assoc with distinct chromosomal translocation 11:22 q24 q12 which results in a chimeric protein EWS/FLI-1
        • Destructive intramedullary lesions that affect the diaphysis
    • Dermatofibrosarcoma: lateral microscopic extensions
      • Check CD34, 30-50
      • Tx/ wide local excision with 4cm
    • GIST: AKA leiomyosarcoma
      • Arise from interstitial cells of cajal: gastric pacemaker cells
      • Expresses CD34 (hematopoetic progenitor cell)
      • Expresses CD 117/c-kit (growth factor receptor)
        • Ckit is an oncogene
      • Can affect any portion of GI tract: stomach most common
      • Sx appear late and are subtle
        • Bleeding and ulceration may occur
        • Obstruction from larger tumor
      • Malignant GIST similar presentation to benign but:
        • Size >5cm
        • High mitotic rate (>10 mitoses/high power field)
        • Necrosis
        • Invasion of other structures
        • Metastases
      • Endoscopy: EUS: shows submucosal tumor: possibly with ulceration
        • Biopsies often nondiagnostic
      • CT scanning of Abd/Pelvis
      • Complete surgical resection best tx if it is possible: 2-4cm margin optimal
        • Survival dependent on size/resectability
        • 75% 5-year survival for smaller resected tumors
        • 20-40% overall for malignant GIST tumors
      • Chemo: C-kit inhibitor: imatinib
        • Indication: metastatic, locally advanced and incompletely resected gist tumor
        • 54% demonstrate tumor reduction: 20% tumor stability
        • ckit oncogene expression: 40% recurrence
        • targets tyrosine kinase inhibitor
      • Recurrence in 40-90% surgically tx pt
        • RF: tumor size, mitotic index, tumor location, tumor rupture during surgery
    • Desmoid: nsaid, sulindac, tamoxifen
    • Retroperioneal Sarcoma:
      • Ddx
        • renal cell, adrenal (primary adrenal coricocarc, pheo)
        • lymphoma (other nodes, b sx, tumor marker ldh)
        • non seminomatous extra gonadal germ cell tumors (Bhcg, afp)
      • Represent 15% of sarcoma
      • Dx delayed d/t lack of sx
        • Usually >10cm at time of presentation
        • 50% are larger then 20cm at diagnosis
      • Liposarc, MFH, and leiomyosarcomas most common
      • Radiologic assessment
        • Chest, abd and pelvic ct scan with IV/PO contrast
        • Assess for liver and lung mets
        • Assess vascular invasion
      • Tx: Complete surgical resection
        • Difficult to achieve tumor free margins
          • on the test you must get 1cm
          • in practice very hard: attempt to get grossly clear margin
        • Achievable in 40-60% of pt
        • Survival 103 mos v 18 mo with incomplete resection
        • Often involves radical extirpative procedures: bowel resection, nephrectomy, pancreatectomy
          • Gluteal tumor: abut the sciatic nerve
          • Fem nerve involvement: lose knee extension
          • Sciatic nerve involvement: lose most leg
          • Local recurrence: chemo and rad pos
      • 5 yr survival 40-50%

Pancreas: eat when you can, sleep when you can, don’t touch the pancreas

  • Pancreas  Basics
    • Anatomy
      • Head: arterial supply:  ant/post sup/inf pancreaticoduodenal
      • Uncinate process part of gland below left renal vein
        • Taken during a whipple
      • Junction of smv and splenic behind neck
    • Exocrine: digestive enzymes and bicarb
      • Trypsin
      • Pepsin-pepsinogen (from stomach)
      • Enzymes don’t act in acidic environment: neutralized by bicarb
      • Secretin: specific for pancreas, most potent stimulator of bicarb secretion
      • Cck: work on gb as well
    • Endocrine: need 20% for full function
      • Beta cells: Insulin
        • Throughout pancreas: 10-25% of blood flow
      • Delta Cells: Somatostatin:
        • great inhibitor: block all endocrine and exocrine production
        • Dec splanchnic pressure
      • Alpha Cells: glucagon
  • Embryopathologies
    • Annular Pancreas: incomplete fusion
      • Assoc with downs: 20%
      • Sx Obstruction
      • Dx UGI contrast or endoscopy
        • Smooth obstruction with dilation proximal
      • Tx Duodenoduodenostomy or duodenojejunostomy
        • No bx, no transection
    • Pancreatic divisum: failure of fusion of dorsal to main pancreatic ducts
      • Major (Wirsung) drains head of panc
      • Lesser (Santorini) drains entire panc
      • 10% of normal population
        • 10% will develop pancreatitis
      • Sx caused by stenosis/obstruction of the lesser papilla
        • Assoc with pancreatitis, not ca
      • Tx minor duct papillotomy
    • Accessory Duct: vestigial dorsal panc with incomplete fusion
      • Opens through minor/lesser papilla: duct of Santorini
      • Most commonly remains in continuity with with panc duct  thus occlusion at duodenum doesn’t create sx
      • 3-14% pt with panc divisum may have obstructed accessory which causes pancreatitis
  • Acute Pancreatitis
    • Incidence 17/100,000, mortality 2-3%/yr
    • Etiology: gallstone>etoh>idiopathic (blockage), vascular, infectious, neoplastic, divisum, cf
    • Sx: Pain (95%), N/V (80%), Distention (75%), Guarding (50%)
    • Biochemical: amylase, lipase, alanine aminotransferase (gallstone panc)
      • Lipase = specific
      • Amylase linked to pancreas, parotid, bowel (trauma) and increased in renal failure
        • rises 2-12 hours: elevation degree doesn’t correlate with severity
    • Imaging:
      • u/s biliary duct
        • 30-60% of pt with biliary etiology will suffer subsequent complications of biliary dz within 3 months if they don’t undergo chole
      • Contrast ct (dynamic for non-perfused panc) best for m&m in first 24 hr
        • A nml
        • B mild edema
        • C peripanc infiltrate
        • D peripanc fluid collection
        • E non enhanced or intrapanc fluid collection- m 57% & m 20%
    • Prognostic Criteria
      • Contrast enhanced
      • Ransons 48 hr
        • 24 hours: GALAW
          • gluc 200, ast 250, ldh 350 (now lactate), age (55), wbc 16
        • 48hrs
          • fluid sequestration 6L, base deficit from acidification, diaphragm inc dec frc dec paO2 <60, bun >5, ca <8
        • 4 = 30-40% mortality, 6 = 80-90% mortality
      • Modified Glasgow
      • Apache 2
    • Basic Tx
      • Hydration
      • Analgesia: opioid
      • NG suction: only beneficial in severe
      • No benefit from somatostatin or h2 blocker
      • Nutritional support: Tpn v Enteral feeds
        • TPN not beneficial
        • Enteral feeds via NJ not NG tube
        • Reduce translocation of bact
        • Promote gut immunity
        • Enhance gut blood flow
        • Dec incidence of infected necrosis
      • Abx: imipenem
        • Fever likely due to inflammatory response, not infection early on
        • Pancreatic necrosis 30-50% get infected
        • Ppx questionable: No benefit in mild pancreatitis
        • Cochrane review 2005 10-14d use dec risk of superinfection
        • GI suggests against it
      • Surg exploration
        • Identification of necrosis
        • When in doubt  of diagnosis or hemorrhagic with continuous bleed or abscess
        • Serial ct is negative initially necrosis can take 3-10 d to manifest
        • Serial debridement required: necrosectomy
        • Open v closed drainage: experience open packing with drainage
        • Mortality 25-30% for infected necrosectomy
        • Peritoneal lavage no role
    • Gallstone pancreatitis
      • Ercp and Lap chole: procedure of choice
        • Ercp reduces septic complication
      • Tx pancreatitis then chole during same admission
        • Labs don’t have to be normal just down trending
      • Open chole and cbd exploration: more morbidity
      • Pancreatitis with porcelain gb
        • Tx pancreatitis then elective cholecystectomy
    • Complications
      • Acute: Hemorrhage, abscess, fistula (biliary, pancreatic enteric, pseduocyst formation, mortality
      • Chronic: Exocrine/endocrine insufficiency, strictures, hernia, pain
      • Pseudocyst 8% (acute alcoholic panc)
        • 30-50% of pt will develop acute fluid collections: most resolve
          • 10% develop pseudocysts at 4 weeks
          • Most common cause of cystic pancreatic lesion
          • Most resolve spontaneously: <6cm <6wks
          • Less likely to resolve if complicated: infection, rupture and hemorrhage
        • Collection MC in lesser sac
        • Sx obstruction, nausea, hyperamylasemia
        • Dx: u/s best
        • Tx:
          • asym no treat
          • sx and/or >6cmat >6wks
            • Drain ext or int (ct and ercp)
            • Percutaneous aspiration: high recurrence rate
            • External drainage for poor operative risk: 20-30% will develop fistula
            • Int: endoscopic cystogastrostomy, laparoscopy
              • Avoid in cirrhotics: presence of perigastric varices
          • Don’t have to biopsy wall unless open procedure; then, biopsy all
          • No need for somatostatin analogue or tpn
      • Abscess 5%: necrotizing pancreatitis
        • Necrotic material that gets infected
        • Mortality 20%
        • Fever white count stranding of surrounding fat
        • Dx fna with g-stain and cx, radiologic gas
        • Tx
          • Abx: imipenem
          • IR if stable
          • Open debridement with planned return
            • higher complication rate: fistulas
          • Closed drainage: close fascia
          • Complication diabetes
      • Hemorrhage 5%
      • Panc Ascites
        • p/w ascites and wt loss
        • Dx: paracentesis: elevated amylase/lipase
          • ercp shows ductal disruption
        • Tx: npo, hyperal, paracentesis if resp issues, somatostatin pos helpful, stenting duct open proximal duct
        • surgery for major duct disruption
      • Fistula: most will close within 4-6wks
        • Somatostatin doesn’t hasten rate of closure
        • ERCP and stent: close fistula in 85% of pt
      • MCx death pulm insufficiency in first week
      • MCx death >2wks sepsis
  • Chronic Pancreatitis
    • Basics
      • MC alcoholic pancreatitis, 40-50y/o, steatorrhea, wt loss
      • Not assoc with pancreatic adeno
      • Autoimmune type dx with bx findings of lymphocytic invasion
        • Assoc with other autoimmune conditions: sjogren’s and ibd
        • Tx non surgical: corticosteroids very effective
    • Sx: Pain continuous, type 2 dm
    • Dx: axr calcified panc
      • Ercp for pre-op
      • Steatorrhea
        • Dx with 24 hour fecal fat collection
        • <20g: intestinal etiology
        • >20g: pancreatic insufficiency
    • Tx
      • Stop PO etoh
      • Etoh injection to celiac for pain
      • Endoscopic sphincterotomy and duct evaluation
    • Surgery Indications
      • Intractable pain: unrelieved by avoidance behavior, medical tx, endoscopic tx
      • Suspicion of underlying carcinoma
      • Ppx against deteriorating panc endocrine and exocrine function
    • Surgery Goals
      • Relieve pain
      • Preserve quality of life
      • Nutritional status: exocrine/endocrine
      • Avoid life long narcs: earlier than later <2 years
      • Avoid chronic pain pathways from developing in the spinal cord and brain
    • Surgical principles
      • Decompression of the pancreatic duct
      • Denervation
      • Resection of abnormal a parenchyma
    • Surgical decompression operations
      • Puestow: lateral pancreaticojejunostomy: need dilated duct
        • Early pain relief 80%
        • 30% recurrent pain within 5 years: 2’ to persistent/recurrent dz in panc head with inadequate drainage
        • Anastomosis should be >6cm and < 10cm (would involve the head)
      • Whipple: pancreaticoduodenectomy
      • Beger: duodenum preserving pancreatic head resection
      • Frey: local resection of the pancreatic head, coring out, with longitudinal pancreaticojejunostomy
      • Whipple/Beger/Frey
        • Similar pain relief b/w 1-4 years in 80% of pt out to 8.5 years
      • Total pancreatectomy
        • Severe pain exocrine and endocrine failure
        • Periop death 5%
        • Complete pain relief 80%
        • 20% disease related death
        • Autoislet txp
          • Can isolate from diseased pancreas
          • Possible for off site pancreatectomy
          • Portal vein/transhepatic pv delivery
          • All pt undergoing pancreatectomy should be considered
      • Cyst-enteric anastomosis: cyst gastrostomy, Roux en Y cyst jejunostomy
      • Duct stenting w or w/o lithotripsy v surgical drainage
        • Endoscopic tx less effective
        • Pain relief in 32% at 2 years
    • Outcome predictors
      • Good outcome predictors
        • >50 yo
        • dz duration < 2 year: limited narc use
        • isolated episodes of pain > constant
        • hx of dm
        • no previous peustow
        • duct >6mm
        • social support
        • inflammatory dz in pancreatic head
      • Poor predictors
        • Dz duration >10 years
        • No dz in panc head
        • Poor results from previous peustow
    • Sympathectomy
      • Transthoracic v transhiatal
      • Indicated prior to total pancreatectomy
      • Selecting pt
      • Small duct
      • Drug seeking behavior, psychogenic dz
      • Differential epidural anesthesia: placebo, splanchnic v somatic blocks: exclude pt who only benefit with placebo
  • Pancreatic Exocrine Neoplasm
    • Cystic Neoplasm
      • Incidental Cyst
        • <2cm without suspicious findings: mri in 1 yr
        • >4cm consider resection
      • Pancreatic cyst: biopsy
        • Mucinous=tumor=resect
        • Serous=observe= 6 mo f/u
      • Amylase, CEA, Viscosity
        • Serous Cystic neoplasm: low, low, low
        • Mucinous Cystic neoplasm: low, high, high
        • Psuedocyst: High, High, Low
    • Serous Cystadenoma
      • Benign, glycogen-rich epithelial lining
      • Don’t communicate with pancreatic ducts
      • Cluster of grapes central scar appearance
      • Cea <5
      • VonHippel Landau: Found in tail, mostly benign
      • Histo: bland cuboidal epithelium
      • Tx
        • Should be left alone
        • Resection for symptoms or cannot r/o malignant
    • Mucinous cystadenoma: malignant potential
      • 30-50% harbor Ca
      • Distal, female, middle aged, peripheral calcifications, pseudocyst
      • No communication with ductal system
      • Single or multiple septations
      • Calcifications or papillary growths indicate ca
      • Histo: ovarian like stroma pathognomonic
      • Cea >250, tumor markers ca 19-9, 72-4, 125, 15.3, mostly malignant
      • Tx Always resection
        • complete resection with regional node dissection
        • Rad role uncertain
      • 5 yr survival 45%
    • Solid Pseudopapillary
      • Young women (80%)/children
        • MC pancreatic tumor in pt under 21
      • In body and tail
      • Locally invasive, rarely metastatic
      • Surgical resection usually curative: 90% cure if localized
    • IPMN
      • Basics
      • Main duct IPMN: MDIPMN: Diffuse or segmental
        • 70% harbor malignancy
        • 45% have invasive caricinoma in resection specimen
      • Mixed type: behave like MDIPMN: tx the same
      • Branch Duct: BDIPMN Usually in head or uncinate but can occur anywhere
        • Variable risk for cancer
          • Size dependent
            • 1-3cm: reimage at 6 mo then CT cross sectional imaging q 1 year
            • >3cm, mural nodules, positive cytology or symptomatic
      • Sx
        • N/V/Abd pain/ back pain/wt loss/ anorexia
        • Pancreatitis
        • Sx of exocrine and endocrine panc insufficiency
        • DM, high hba1c
      • Grading
        • Low grade dysplasia-adenoma
        • Moderate: Borderline
        • High: invasive
      • Surgical Indication
        • Symptoms
        • Recurrent pancreatitis
        • Communication with main duct
        • Cancer/risk for developing
          • IPMN  are thought to follow an orderly progression from a benign neoplasm to ca
      • Size dictates plan
        • 1cm 17% (probably lower) Ca risk
          • <1cm: mri/ct at 1 year
        • <2 cm with mural nodule 25% Ca risk
        • >2 cm regardless of nodule 27% Ca risk
          • 1-3cm: eus plus mrcp/ercp
            • high risk: resect
            • Low risk: early repeat of mr/ct
        • <3cm: inc factors
          • older age
          • presence of sx
          • dm
          • Specific radiographic features:
            • solid component
            • main panc ductal dilation >5mm
            • lymphadenopathy
            • presence of mural nodules
            • presence of synchronous lesions
            • an inc in cyst size during follow up
          • Without mural nodules risk of malignancy <40%
          • Cytology
            • HGA: high grade atypia: most sensitive predictor of Ca in all cysts and in small <30mm bd ipmn
            • Cytology detected 30% more cancers in small cysts than dilated MDIPMN or mural nodules
          • Progression to malignancy 5-6 years, varies with subtype
            • Colloid carcinoma 30-50% pt with intestinal type ipmn
            • Ductal adenoca develops in >50% pancreaticobiliary type ipmn, 10-30% gastric branch ipmn
        • >3 cm = resection
      • Recurrence after resection 17%
        • 28% at 2 years
    • Adeno (95%)
      • Basics
        • 33,000 new cases 32,000 deaths/yr
        • Risk: tobacco x2, meat x2.5, endogenous cck, genetic 3-5% (85% k-ras mutation)
        • Age, M>F, Blacks
        • Assoc: dm, chronic panc, smoking, etoh
        • 92% adeno, 5% cystadeno, 3% acinar cell
        • Sx jaundice back pain, migratory thrombophlebitis
      • Dx double duct sign in contrast ercp/mrcp of terminal bile and panc duct
        • Poor yield: CT, fna, duct cytology
        • 85% Ca 19-9, ca 50%, ca 125 (peritoneal carcinomatosis)
      • Adeno Location 75% in head 20 % body 5% tail
        • 65% distant mets
        • 15% locally advanced:
          • chemorad: med survival 17 mo
          • no chemorad 7 mo
        • 20% resectable
      • CT staging: Contrast enhanced CT with 1mm cuts: pancreas protocol
        • High predictive value for unresectability: 90-100%
          • Obvious vascular invasion
          • Distant metastases
        • Low predictive value for resectability: May miss subtle vasc invasion
      • EUS: when to perform
        • Suspected panc mass and negative ct
        • Staging: particularly with ct showing resectable lesion
        • Tissue Dx
        • Unresectable dz: tissue is the issue: neoadjuvant/palliative chemo
      • Poor surgical candidates
        • Median survival
          • Resectable: 24-30mo
          • Local advanced 10-18mo
          • Metastatic 6-10mo
        • Systemic therapy not very effective
      • Pre-Op
        • coagulopathy (vit k)
        • No role for pre-op hyperal: no imp survival
        • Pre-op biliary drainage: no role, elevated infectious complication
        • Major controversy: if surgery planned soon, don’t 2’ infectious issues
        • Stent or not
        • Plastic metal
        • Covered uncovered
        • Factors affecting survival: tumor left at resection, tumor diameter, dna content, LN status
      • Not Operable:
        • LN: celiac, base of mesentery, sma, LN portal mesentery
        • Options
          • Locally invasive without liver mets:
            • Biliary bypass and chemorad (gemcitabine and external beam rad): inc median survival 6 to 22 mo
              • Bypass to cbd or gb
          • Gastric bypass for actual (pre-mortal) or pending obstruction
          • Duodenal stent v gastrojej: duodenal stent faster for enteral feeds to start but less long term durability
          • Biliary stent placement: Covered metal better: endoscopic better
          • Celiac plexus neurolysis: moderately effective
          • Palliative resection more morbid than bypass without significant change in survival
            • 8.2mo palliative 6.4 mo. Bypass
      • Operable
        • Stage 1&2 with 2b: locally advanced borderline resectable
        • Stage 3 unresectable for cure
          • 2cm, LN to spleen, peripancreatic, LN prepyloric, LN colon mesentery, part of smvsma
          • Peripanc nodes still ok
          • Celiac lymph nodes not ok
          • Portal vein resection has equivalent survival as those without pv involvement so long as rest of stage is no different
          • No benefit in resecting artery
          • No benefit to extended lymphadenectomy
        • Op mortality whipple should be <3%
        • Age isnt a c/i though morbidity higher and survival less
          • Complications inc with age and bmi
        • Neoadjuvant tx appears to offer benefit to 20% of pt
          • Gemcitabine based: Improves progression free survival but greater toxicity
          • Rarely converts unresectable to resectable
        • Adjuvant tx is standard for >stage 2 but additional survival still limited
          • Up to 30% never get it d/t complications
        • Dx Laparoscopy
          • Detects carcinomatosis in most pt (ct as sensitive)
          • Reduces morbitdity and avoids needless laparotomy in most pt with carcinomatosis
          • Reduces costs if yield is 10%
          • Improves staging for subsequent tx
          • Eliminates expensive, useless tx
          • Predictor for pt, clinical trials
        • Laparoscopic whipple:
          • Benefit from distal, subtotal, medial,
          • Reduced los complications
          • Improved QOL
          • Median survival <2years
        • Pancreaticoduodenectomy 10% 5 yr survival
          • Pylorus sparing no better than distal gastrectomy
          • Pyloric preserving done 2’ to dumping symptom risk
          • Mucosal anastomosis of panc duct commonly thought to make less fistula, not true
          • No advantage for total pancreatectomy
          • Expect an intense desmoplastic reaction by tumor
        • Complications
          • Leak 15-25% of cases: most heal with conservative mgmt
            • Octreotide
          • Fistula: 10-40%
            • RF: small duct, soft pancreas, bmi, poor nutrition
            • Octreotide
            • Decreases fistula output
            • Doesn’t affect periop pancreatitis, postop mortality, reoperation rates, icu stay
      • Mets: gemcitabine
  • PNET: Pancreatic neuroendocrine tumors, pancreatic islet cell tumors, pancreatic endocrine tumors
    • Basics
      • Ddx
        • Adeno: much more common
        • Carcinoid
      • Most spontaneous, 10% assoc with MEN1, vonHippel landau, tuberous sclerosis, neurofibromatosis
      • Most nonfunctional and not assoc with hormone hypersecretion
      • Prolonged silent progression
      • Incidental find
      • CT will find 70% of 3cm and 50% of 1cm
      • 50% will have liver mets
      • Serum marker CGA chromogranin A
      • Tx
        • Without mets: parenchymal sparing resection
        • With mets: possible surgical debulking
          • Localized liver: resect
          • Diffuse: chemo
        • Chemo: survival benefit
          • Streptozocin and doxorubicin and 5fu: 37mo survival rate
          • Temozolomide single agent or with capecitabine
          • Bevacizumab, sunitinib, sorafenib
    • Insulinoma
      • MC functional neuroendocrine tumor
      • Basics
        • From beta cells though out panc
        • Females, b/w 40-50
        • most <1.5 cm
        • multiple in familial type
        • children dysidoblastosis
        • majority benign: 20% malig
      • P/w hypoglycemia on fasting or after exercise: resuscitate
        • npo with iv saline
        • check blood gluc q 6, if doesn’t drop <50 in 72 hr done
        • if drops: insulin, c-peptide draw then give gluc
        • visual disturbance mc sx
      • dx: whipple’s triad (within 3 d fast)
        • serum insulin high (c-peptide)
        • fasting <45mg/dl
        • hypogly sx
        • 72 hour fast under monitored conditions: glucose <45 with serum insulin higher than 5 and high c-peptide >0.7 and proinsulin
        • r/o factitious hypoglecmia with c-peptide and proinsulin levels
        • ct scan, fractionated portal blood,
        • octreotide not helpful
        • somatostatin receptor scintigraphy don’t work to image
      • Tx: surgical exploration
        • Intraop u/s: resection location based
        • Distal pancreatectomy
        • Enucleation in body and head
        • Resect metastatic lesion
        • Chemo
          • Diazoxide
          • Dilantin
          • Ocreotide
          • Streptazosin
    • Gastrinoma
      • Basics
      • Incidence: .5-3/100,000
        • Second MC functional neuroendocrine tumor
        • 30% familial (men1), 70% sporadic
        • 60% malignant
        • Usually multicentric
        • 2M>F
      • Gastrinoma triangle: duodenum wall mc
        • Cystic to cbd, portion 2-3 duodenum, panc head and neck
      • Sx Acid secretion: pain & diarrhea
      • Dx basal acid o/p >15 meq/hr
        • post antrectomy >5 meq/hr
        • basal/max >0.6  (close to 1)
        • fasting serum gastin level (>500)
      • gastrin assay high gastrin, high acid (ph 2.5)
        • no acid: pernicious anemia
      • stimulation study
        • Ca infusion: gastrin must go up by 400
        • Secretin infusion: must go up 100 over baseline (over 200)
          • must be off PPI for 1 wk, bridge with h2 blockers
          • ppI increase serum gastrin 5x
          • hold h2 blockers 24hrs prior to test
      • Localize lesion
      • Ct scan: 60%, U/s: 60%, Angio: 60%
          • EUS better for pancreatic  than duodenal tumors (can ID only 50%)
          • Intraopduodenotomy for localization
        • Somatostatin receptor scintigraphy with single photon emission computed tomography
          • Most sensitive tests: 80-85% Tx of choice
        • Fractionated portal venous blood: 95% (hemobilia, intraperitoneal hemorrhage)
      • Manage
        • Familial: not for operation
          • Medical management: check hypercalcemia men-1, ctrl this
          • Ctrl acid with ppi
          • Med management fails, Highly selective vagotomy (worsens diarrhea)
          • Simvastatin
          • Med management fails: last resort total gastrectomy
        • Sporadic
          • Enucleation, excision
        • Metastatic:
          • Can enucleate
          • Total gastrectomy
          • Simvastatin
          • Chemo
            • Streptazosin: most effective
              • Diabetic after 1 dose
      • ZES: Zollinger-Ellison Syndrome
        • Sx: Refractory Ulcers, Diarrhea
        • Distal cluster of H pylori neg ulcers
    • VIPoma
      • 50y/o,  Solitary >3cm
      • 50% malignant: can include  somatostatin, glucagon, insulin
      • Sx watery dia, achlorhydria, hypoK
      • Dx: Localize with octreotide scan
      • Tx
        • Correct elyte, fluid and dia
        • Excise lesion
        • If in liver excise liver lesion
    • Glucagonoma
      • Basics: 60-80% malignant found 80% in the tail and body
      • Sx: 4D’s: diabetes, dermatitis, DVT, and depression
        • Dermatitis 90%: migratory dermatitis: pathogmnomonic
        • Necrolytic migratory erythema: predates other systemic symptoms
        • Dm 90%
        • Wt loss 90%
        • Anemia, abd pain, diarrhea, dvt, pe (10%)
          • Anemia: kupfer metabolism imp in hemoglobin metabolism
        • Hypocholesterolemia
      • Dx: ct scan
        • Octreotide scan
      • Tx: resection/ablation
        • Octreotide: worsen dm, improve skin
    • Somatostatinoma
      • Basics
        • 1: 40mill
        • Assoc with NF
        • Present very large, commonly with gallstones from cholestasis
        • 90% Malig
      • 75% panc, 25% sb and periampulary/duodenal wall
      • Sx diabetes, cholelithiasis, steatorrhea, jaundiced and level >10
        • Hyperchlohydria
      • Dx/ Octreotide scan
      • Tx/ Resection

Skin Cancer: Melanoma, BCC, SCC, etc

Skin Cancer

  • Skin Cancer:
    • 40% of all cancer cases
    • >1 million cases/yr
    • 40-50% US population affected
    • 95% curable
    • Geographic risk: highest rates of UV radiation: South Africa and Australia; In US Florida and Texas
  • Melanoma
    • Increasing in incidence
      • US: inc from 1:1500 (1935) to 1:74 (today)
    • Risk factors:
      • IMG_6695Familial: skin type and color; h/o malignant melanoma
        • White men highest risk
      •  Environmental
        • >3 blistering sunburns before age 20
        • Outdoor jobs >3 years in adolescent years
        • Use of sunlamps and tanning beds
      • Other
        • Actinic keratosis, elastosis
        • Marked freckling on upper back
        • Large number of normal nevi
        • Atypical nevi, congenital giant nevi
    •  Characteristics
      • Asymmetrical: one half the lesion is shaped differently
      • Border: irregular, blurred or ragged
      • Color: inconsistent pigmentation with varying shades of black or brown
      • Diameter: >6mm or a progressive change in size
      • Evolution: history of change of lesion
    • Types
      • Superficial Spreading (60%): prolonged radial growth phase, notching scalloping, areas of regression
      • Nodular: (15%): darker and thicker than superficial spreading, rapid onset; commonly blue-black or blue-red (5% amelanotic)
      • Lentigo Maligna (%5) enlarge slowly, usually large, flat, tan or brown
      • Acral Lentiginous: (rare: Asians 46%, blacks 70%) on soles, palms, subungual, usually large, tan or brown, irregular borders. Anti-reggae.
      • Desmoplastic (1.7%) rare locally aggressive, occur primarily on neck and head in elderly
    • Dx
      • <1.5cm : excisional biopsy
      • >1.5cm: Incisional Biopsy
      • Punch biopsy OK: look at ‘worst’ part
        • Goals
          • Narrow excisional bx: 2-3mm
          • Rule out lesions with potentially similar features:
            • seborrheic keratosis
            • pigmented basal cell ca
            • solar lentigines
            • atypical nevi
          • Determine depth of invasion
          • Identify prognostic features of the primary: ulceration and regression
      • Tests: get LDH (terrible prognosis, upstages), LFT
    • Staging: Breslow
      • T1            0-.75mm              Thin
      • T2            .75-1.49mm        Intermed
      • T3a         1.5-3.0mm           Intermed
      • T3b         3.01-4mm            Intermed
      • T4            >4mm                  Thick
    • Prognostic factors:
      • MULD: Mitotic rate, Ulceration, LDH, Depth of invasion
      • Male sex
      • Trunk/head and neck
      • Age:
        • Mortality increases with increasing age
        • Lymph node metastases higher in younger patients
      • Nodular sub-type
      • High mitotic rate (>6 mm2)
    • Recommended margins
      • Melanoma in Situ: 5mm
      • <1mm = 1cm
      • 1-2mm = 1-2cm
      • >2mm = 2 cm
      • May be modiefied by anatomic considerations
      • Negative peripheral margins important in ill defined lentigo maligna lesions
      • On the digits: Amputation at least one joint proximal to the tumor and sentinel node bx
    • Risk of nodal disease
      • <1mm w/o ulceration <5%
      • 1-4mm = 20%
      • >4mm = 35%
    • Sentinel Lymph Node Bx:
      • Radiocolloid and vital blue dye (given intradermal) improve accuracy
      • Excision of primary should occur at time of SLNB
      • Can be performed after: no decrement in identifying SLN after previous wide excision
      • Indications:  >1mm, any ulcerated, >1 mitosis/mm2
        • All pt with invasive melanoma
        • Primary melanoma >1 mm
        • M75 with ulceration, deep invasion, regression, truncal location, and mitoses
        • Pt with nevomelanocytic lesions assessed by bx in which biology is uncertain
      • If positive: 2.2x risk of recurrence and deaths
    • Lymphadenectomy
      • Deep inguinal lymph node dissection for: > 4 positive lymph nodes on superficial dissection, positive Cloques node (subinguinal), enlarged ileo-obturator lymph nodes on CT, clinically palpable or extracapsular invasion of femoral lymph nodes
      • A/E: 30% have lymphedema, wound complications, or other a/e
    • MSLT2 trial: positive node: dissection or u/s obs
    • 5 year survival: depth, with and w/o ulceration
      • <1mm   95%       91%
      • 1-2mm 89%       77%
      • 2-4mm 78%       63%
      • >4mm   67%       45%
    • Adjuvant Therapy: chemo, biochemo, immune, braf inhibitor
      • Adjuvant for high risk melanoma: significantly prolongs relapse free survival, 26% risk reduction
        • 15% overall survival improvement, 1 year benefit
        • stage 4 (6-9mo median survival, 5 year 6%)
      •  Indication: Pt high risk for systemic dz
        • Ulcerated
        • Positive LN
          • In transit tumor cells
        • Thick primary >4mm
        • Regional Recurrence
      • Chemo
        • Dacarbazine: response 20%, no change in survival
        • Temozalmide: oral agent, crosses bbbb, no change in survival
        • Combo: Cisplatin, vinblastine, dacarbazine
          • Improved response 25-30%, no change in survival
      • Immunotherapy:
        • IL2
          • T cell growth factor, produced by t cells
          • Induces T and NK cell proliferation
          • Strong anti tumor properties
          • Approved for melanoma and renal cell
        • INFalpha
          • IFN alpha 2b: for stage 3
          • Survival benefit 1 month
      • Targeted therapies:
        • Zelboraf: vemurafanib: inhibitory molecule selective for V600E mutation
          • BRAF: mutated: acquired to activate map kinase pathway
          • Selects out the 40-60% of melanoma with NRAF mutation
          • Response rate 48%, survival at 6 mo 84 v 64 with dacabazine as control
          • Unknown MOA: protein death 1
          • A/e cutaneous scc and keratoacanthoma
      • MAB:
        • Ipilimumab & nivolumab trial for metastatic tx/ 4 mo gain (10mo total)
        • Ipilimumab: CTL4 blocker: increases antitumor T cell survival
          • A/e: colitis, rash, elevated LFTs
          • Increased survival rates 21 v 12% v vaccine
    • Metastatic Melanoma
      • Considerations: Prior disease free interval, sites of dz, amount of tumor burden, ability to resect entire disease, pt performance, potential to down stage with systemic therapy
    • Mucosal melanoma: poor actors: locally excise
      • Unlikely to have braf mutation
    • Occular melanoma: go to liver even after enucleation
      • Ckit mutation: studying gleevec
  • Seborrhaic Keratosis
    • MC benign skin tumor
      • Ddx melanoma
    • Greasy/waxy stuck on raised appearance, oval
    • Clonal origin: neoplastic not hyperplastic
    • RF: sun exposure , age
      • Familial predisposition with postulated AD inheritance
    • MC location: face, neck, back
      • Never found on mucosa, palms or soles
      • “Never occur before 30”
    • Can spontaneous regress, assoc with pregnancy, inflammatory skin conditions and malignancy
    •  Tx: Ablative: cryotherapy, laser, electrodessication, surgical
  • Basal Cell
    • Basics
      • MC skin cancer 90%
      • Arise from lowest layer of the skin
      • Rarely metastasize or spread
      • RF: UV radiation: Sun exposed areas
        • Canthi of eye and nose
        • 86% on face
      • Failure to heal
      • Indolent
    • MC: modular type: face; waxy central cupping no ulceration
    • Superficial scaly plaque, sm compared to squamous cell 15% and truncal, no raised edges
    • Tx MOHs surgery: tangential/ transverse chemo fix and map and plan next cut: failure rate less than half other modalities; involve plastic surgeon; cold knife or radiate, can freeze, electodesicate;
      • If recurrence: more MOHs
    • mets very rare, occur only if neglected
      • no chemo no LN resections
      • Txlocal excision with clean margin’s
    • 2-3mm margin
  • Squamous cell
    • RF: UV: exposure, chronic inflam sites, long standing wounds: scar, burn, pilonidal, anal fistulae, xeroderma
    • Tx goal: complete removal: excision with narrow margin is acceptable
      • Curettage: dermatologist
      • Cryotherapy: liquid nitrogen
      • Mohs Surgery: Best for face, neck, hands
      • Radiation Therapy: inaccessible locations, recurrence
      • Topical Chemotherapy: fluorouracil
      • Surgical: 2-3mm margin
  • Merkel Cell Carcinoma
    • Cutaneous neuroendocrine tumor with keratin filaments and cytoplasmic dense core neuroendocrine granules
    • Oval shaped synaptic receptor cells
    • RF: UV, ICed, polyomavirus
      • Occurs in sun damaged skin and lymphatic spread is common
      • More common in immunosupporessed
    • tx wide excision 1-2cm margin with SNLBx and positive in most
    • Chemo: platinum
    • Rad: >2cm do radiation
    • Bad prognosis, high propensity for local recurrence
  •  Bowen
    • Carcinoma in situ of the skin
    • RF: sun exposure, chronic immunosuprresion, hpv
    • Tx: WLE
  • Spitz Nevi
    • Solitary benign melanotic proliferations
    • Children < 10 y/o
      • Pink/red and dome shaped
      • Pattern: starburst transitions to reticular
    • Adults: brown or black
      • Tx: Excision with 2mm margin