NEET SS Surgical Gastroenterology (MCh) Syllabus

What operation is standard for resectable cancer of the head of the pancreas, and what does it involve?

Pancreaticoduodenectomy (Whipple procedure): resection of the pancreatic head, duodenum, gallbladder, distal common bile duct, and (in classic version) the gastric antrum. Reconstruction = pancreaticojejunostomy, hepaticojejunostomy, and gastro/duodenojejunostomy. Pylorus-preserving variant (PPPD) spares the antrum/pylorus.

What vascular criteria define 'borderline resectable' pancreatic cancer?

Tumor contact <=180 degrees with the SMA/celiac axis, OR contact with the SMV/portal vein causing venous narrowing/contour irregularity or short-segment occlusion that is reconstructable, OR short-segment contact/abutment of the common hepatic artery. >180 degrees arterial encasement = locally advanced/unresectable.

What is the most common cause of mortality and the most common complication after a Whipple procedure?

Most common complication: postoperative pancreatic fistula (POPF). Other major complications include delayed gastric emptying and post-pancreatectomy hemorrhage; POPF and its sequelae (e.g., erosion causing hemorrhage) are leading causes of mortality.

What is the tumor marker most associated with pancreatic adenocarcinoma, and a key caveat?

CA 19-9. Caveat: it can be falsely elevated in biliary obstruction/cholangitis and is undetectable in Lewis-antigen-negative individuals (~5-10% of people), so it is used for prognosis/monitoring, not screening/diagnosis alone.

In chronic pancreatitis, what is the Puestow (modified, Partington-Rochelle) procedure, and its main indication?

Lateral pancreaticojejunostomy — a side-to-side drainage of a dilated main pancreatic duct (>=7 mm) into a Roux-en-Y jejunal limb. Indicated for intractable pain with a dilated duct ('big duct' disease) without an inflammatory head mass.

What are the Frey and Beger procedures for chronic pancreatitis, and how do they differ?

Both treat chronic pancreatitis with an inflammatory head mass. Beger: duodenum-preserving pancreatic head resection with division of the gland over the portal vein. Frey: local coring-out of the pancreatic head combined with a longitudinal lateral pancreaticojejunostomy (no neck division). Frey is technically simpler and combines resection + drainage.

What is the most common cause of chronic pancreatitis worldwide vs. the classic cause of tropical (idiopathic) chronic pancreatitis?

Worldwide most common: chronic alcohol use. Tropical chronic pancreatitis: idiopathic, seen in young non-alcoholic patients in tropical regions, often with large intraductal calculi and early-onset diabetes (fibrocalculous pancreatic diabetes).

What is the most common functioning pancreatic neuroendocrine tumor, and its classic clinical triad?

Insulinoma. Whipple's triad: symptoms of hypoglycemia during fasting, documented low blood glucose (<50 mg/dL), and relief of symptoms after glucose administration. Most are benign and solitary; treatment is enucleation.

What is the Zollinger-Ellison syndrome, and the 'passaro triangle' (gastrinoma triangle)?

ZES = gastrinoma causing gastric acid hypersecretion and refractory peptic ulcers. The gastrinoma triangle is bounded by: junction of cystic/common bile duct (superior), junction of 2nd/3rd part of duodenum (inferior), and junction of the pancreatic neck/body (medial) — where most gastrinomas are found.

How are pancreatic cystic neoplasms differentiated: serous cystadenoma vs. mucinous cystic neoplasm (MCN) vs. IPMN?

Serous cystadenoma: benign, microcystic 'honeycomb' with central scar, older women, no malignant potential. MCN: mucinous, almost exclusively women (body/tail), 'ovarian-type' stroma, premalignant -> resect. IPMN: mucin-producing, communicates with pancreatic duct; main-duct IPMN has high malignant potential (resect), branch-duct can be surveilled if low-risk.

What are the 'high-risk stigmata' that mandate resection of an IPMN?

Obstructive jaundice with a cystic head lesion, an enhancing mural nodule >=5 mm, and main pancreatic duct dilation >=10 mm. 'Worrisome features' (e.g., cyst >=3 cm, duct 5-9 mm, thickened walls) prompt EUS rather than immediate resection.

What is the most common type of esophageal cancer worldwide vs. in Western countries, and key risk factors for each?

Worldwide most common: squamous cell carcinoma (risk: smoking, alcohol, hot beverages, achalasia, lye stricture). Western/rising: adenocarcinoma of the distal esophagus/GEJ (risk: GERD, Barrett's esophagus, obesity).

What is achalasia, and what are the manometric and contrast findings?

A primary esophageal motility disorder from loss of myenteric (Auerbach) plexus inhibitory neurons. Manometry: failure of LES relaxation (elevated integrated relaxation pressure) with absent peristalsis. Barium swallow: dilated esophagus with a smooth 'bird's beak' tapering at the GEJ.

What is the surgical treatment of achalasia and the key step added to prevent reflux?

Laparoscopic Heller myotomy — division of the LES muscle fibers — combined with a partial fundoplication (e.g., Dor anterior or Toupet posterior) to prevent post-myotomy GERD. POEM (per-oral endoscopic myotomy) is an endoscopic alternative.

Compare the Ivor-Lewis and transhiatal approaches to esophagectomy.

Ivor-Lewis: laparotomy + right thoracotomy with an intrathoracic anastomosis; good mediastinal nodal clearance but an intrathoracic leak is dangerous. Transhiatal: abdominal + cervical incisions, blunt mediastinal dissection, cervical anastomosis; avoids thoracotomy, a neck leak is more easily managed but offers less direct mid-thoracic nodal dissection.

What is the most common type of gastric cancer and the Lauren classification?

Adenocarcinoma. Lauren classification: Intestinal type (well-differentiated, glandular, distal, older patients, environmental/H. pylori-related, better prognosis) vs. Diffuse type (poorly cohesive/signet-ring, infiltrative -> linitis plastica, younger patients, worse prognosis, E-cadherin/CDH1 mutations).

Define a D2 lymphadenectomy for gastric cancer.

Removal of the perigastric nodes (D1 stations) PLUS the nodes along the named arteries — left gastric, common hepatic, splenic, and celiac arteries (stations 7-12). D2 is the standard of care for resectable gastric cancer to achieve adequate nodal staging and clearance.

What are GISTs, the marker that defines them, and the threshold for malignant risk by size/mitoses?

Gastrointestinal Stromal Tumors arise from the interstitial cells of Cajal and stain positive for CD117 (KIT) and DOG1. Risk rises with size >5 cm and mitotic count >5 per 50 HPF. Treatment: resection with negative margins (no formal lymphadenectomy); imatinib for high-risk/metastatic disease (KIT/PDGFRA mutations).

What is the modified Johnson classification of gastric ulcers and its surgical relevance?

Type I: lesser curve/incisura (not acid-related, normal/low acid). Type II: gastric + duodenal ulcer (high acid). Type III: prepyloric (high acid). Type IV: high on lesser curve near GE junction. Type V: anywhere, NSAID-related. Types II and III are acid-driven; Type IV is hardest to resect.

What are the four classic surgical complications/sequelae of vagotomy/gastric surgery (post-gastrectomy syndromes)?

Dumping syndrome (early osmotic/late hypoglycemic), afferent loop syndrome, alkaline (bile) reflux gastritis, and postvagotomy diarrhea. Also nutritional deficiencies (iron, B12, calcium) and increased gastric remnant cancer risk.

What is the modern first-line management of a perforated duodenal peptic ulcer?

Resuscitation, antibiotics, and surgical repair — most commonly a Graham omental (omentopexy) patch over the perforation, with H. pylori eradication and PPI therapy postoperatively. Definitive acid-reducing surgery is rarely needed in the PPI/H. pylori era.

What is the TNM-independent rule of '12 lymph nodes' in colorectal cancer, and what defines stage III?

At least 12 lymph nodes should be examined for accurate staging. Stage III = any regional lymph node metastasis (N1/N2) regardless of T stage, with no distant metastasis; it mandates adjuvant chemotherapy (typically FOLFOX/CAPOX).

What defines a 'low anterior resection' vs. 'abdominoperineal resection' (APR) for rectal cancer?

Low Anterior Resection (LAR): rectal resection with sphincter preservation and a colorectal/coloanal anastomosis (for mid/upper tumors with adequate distal margin). APR: removal of the rectum AND anus with permanent end colostomy, for very low tumors involving the sphincter complex. Both should include total mesorectal excision (TME).

What is Total Mesorectal Excision (TME) and why is it important?

Sharp dissection of the entire rectum within its intact mesorectal envelope (the 'holy plane'), removing the rectum with its surrounding fat and lymphatics as one package. It dramatically reduces local recurrence and improves survival in rectal cancer; a positive circumferential resection margin (CRM) is a key predictor of recurrence.

In Crohn's disease vs. ulcerative colitis, what surgical principle governs bowel resection?

Crohn's: bowel-conserving surgery (resect only grossly involved segment with limited margins or stricturoplasty) because disease recurs and is transmural/skip-lesion; surgery is NOT curative. UC: total proctocolectomy is curative; restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the standard elective operation.

What defines short bowel syndrome and the approximate residual small-bowel length thresholds for parenteral nutrition dependence?

Short bowel syndrome = malabsorption from loss of functional small-bowel length (usually <200 cm remaining). Long-term parenteral nutrition is typically needed with <100 cm of small bowel without colon in continuity, or <60 cm with colon. The ileocecal valve and intact colon improve adaptation.

What is the autologous intestinal lengthening surgery for short bowel syndrome, and name the two main techniques?

Used to lengthen dilated residual bowel to improve enteral autonomy: the Bianchi procedure (longitudinal intestinal lengthening and tailoring, LILT) and the STEP procedure (Serial Transverse Enteroplasty). STEP creates a zigzag lumen via serial staple firings and is technically simpler than Bianchi.

What is the most common cause of small bowel obstruction in adults vs. in the virgin (non-operated) abdomen?

Most common overall: postoperative adhesions. In a patient with no prior surgery (virgin abdomen): hernia is the most common cause (then malignancy/intussusception). In children, intussusception is a leading cause.

What is the most feared injury in laparoscopic surgery during Veress needle/trocar insertion, and how is intra-abdominal CO2 pressure typically maintained?

Major vascular injury (e.g., aorta/iliac vessels) or bowel injury during blind insertion (open Hasson technique reduces this risk). Pneumoperitoneum for laparoscopy is maintained at ~12-15 mmHg of CO2 insufflation.

What is the role of ERCP vs. EUS in pancreaticobiliary disease, and a key complication of ERCP?

ERCP is primarily therapeutic (stone extraction, stenting, sphincterotomy) for biliary/pancreatic ductal pathology; EUS is primarily diagnostic/staging plus fine-needle aspiration of pancreatic masses and cyst sampling. The most common serious ERCP complication is post-ERCP pancreatitis (others: bleeding, perforation, cholangitis).