Pancreatic Neoplasms

Intro to Pancreatic Tumors - The Gland's Bad Seeds

Pancreatic neoplasms are primarily malignant, arising from exocrine or endocrine cells.

• Major Types:
  • Exocrine (~95%): Pancreatic Ductal Adenocarcinoma (PDAC) is most common. Others: IPMN, MCN.
  • Endocrine (PanNETs, ~5%): Insulinoma, gastrinoma.
• Key Risk Factors:
  • Smoking (doubles risk 🚬)
  • Chronic pancreatitis
  • Diabetes Mellitus (long-standing)
  • Obesity & ↑Age
  • Family Hx/Genetics (BRCA1/2, Peutz-Jeghers, Lynch syndrome).

⭐ Courvoisier's Law: Palpable, non-tender gallbladder with jaundice is unlikely due to gallstones (suggests pancreatic/biliary cancer).

Pancreatic Ductal Adenocarcinoma (PDAC) - The Silent Killer

• Most common pancreatic cancer (~90%), highly aggressive with dismal prognosis.
• Genetics: Key mutations include KRAS (>90%), TP53, CDKN2A (p16), SMAD4 (DPC4).
• Precursor Lesions: Pancreatic Intraepithelial Neoplasia (PanINs).
• Pathology:
  • Gross: Ill-defined, firm, grey-white mass; often in pancreatic head (obstructive jaundice).
  • Micro: Infiltrating glands/ducts, marked desmoplastic stroma, perineural invasion common.
• Clinical Features: Often "silent" until advanced stage.
  • Painless, progressive jaundice (if head involved).
  • Courvoisier's sign: Palpable, non-tender gallbladder with jaundice.
  • Trousseau's syndrome: Migratory thrombophlebitis.
  • Late: Significant weight loss, anorexia, abdominal/back pain.
• Tumor Marker: CA19-9 (for monitoring response/recurrence, not screening).

⭐ Courvoisier's sign: A palpable, non-tender gallbladder with jaundice. Highly suggestive of periampullary malignancy (e.g., PDAC head), not gallstones.

Cystic Neoplasms of Pancreas - Pancreas's Puzzling Pockets

Four main types with distinct clinico-pathological features and varying malignant potential, crucial for management decisions:

⭐ MCNs are characterized by ovarian-type stroma and occur almost exclusively (95%) in middle-aged women, typically in the pancreatic body/tail.

📌 SPN: Solid Pseudopapillary Neoplasm - Seen in Pretty Nice (Young) females.

Pancreatic Neuroendocrine Tumors (PanNETs) - Hormone Hotspots

• Islet cell origin; functional (hormone excess) or non-functional.
• Micro: "Salt-and-pepper" chromatin, nested growth.
• Functional PanNETs:

  Tumor	Hormone	Key Features
  Insulinoma	Insulin	Whipple's triad (📌), hypoglycemia
  Gastrinoma	Gastrin	ZES, peptic ulcers
  Glucagonoma	Glucagon	4Ds: Dermatitis (NME), Diabetes, DVT, Depression
  VIPoma	VIP	WDHA: Watery Diarrhea, Hypokalemia, Achlorhydria
  Somatostatinoma	Somatostatin	Diabetes, steatorrhea, gallstones, ↓HCl

⭐ Insulinoma: most common functional PanNET, ~90% benign. Whipple's triad: symptoms of hypoglycemia, plasma glucose <50 mg/dL, relief with glucose. oka

High‑Yield Points - ⚡ Biggest Takeaways

• PDAC: Most common, pancreatic head, presents with painless obstructive jaundice.
• Courvoisier's law: Palpable, non-tender gallbladder with jaundice suggests periampullary tumor.
• CA 19-9: Primary tumor marker for PDAC, aids prognosis and recurrence monitoring.
• K-ras mutation: Most frequent genetic alteration; p53, SMAD4, CDKN2A also common.
• Whipple procedure: Standard curative surgery for resectable pancreatic head cancers.
• Trousseau syndrome: Migratory thrombophlebitis, a key paraneoplastic sign in pancreatic cancer.
• PanNETs: Insulinomas (hypoglycemia) and gastrinomas (Zollinger-Ellison Syndrome/ZES) are key types.