A 52-year-old man from rural Maharashtra presents with a 3-week history of progressive jaundice, pale stools, and dark urine. He reports no abdominal pain, fever, or pruritus. On examination, he is afebrile, with mild hepatomegaly and a palpable gallbladder. Laboratory investigations show: total bilirubin 8.2 mg/dL (conjugated 6.8 mg/dL), ALP 320 U/L, GGT 280 U/L, ALT 85 U/L, AST 92 U/L. Ultrasound abdomen reveals dilated intrahepatic and extrahepatic bile ducts with a 2.5 cm hypoechoic lesion at the pancreatic head. What is the most likely diagnosis?

Explanation

## Clinical Diagnosis: Pancreatic Adenocarcinoma ### Key Features in This Case **Key Point:** The combination of **painless progressive jaundice**, **pale stools**, **dilated bile ducts**, and a **pancreatic head mass** on imaging is pathognomonic for pancreatic cancer until proven otherwise. **High-Yield:** Courvoisier sign (palpable gallbladder + jaundice) suggests obstruction distal to the cystic duct — classic for pancreatic head malignancy, not stones (which cause fibrosis and a non-distensible gallbladder). ### Biochemical Pattern | Parameter | Finding | Interpretation | |-----------|---------|----------------| | **Bilirubin (conjugated > 60%)** | 6.8/8.2 mg/dL | Obstructive/cholestatic pattern | | **ALP/GGT elevation** | 320/280 U/L | Bile duct obstruction | | **Transaminases (mild)** | ALT 85, AST 92 | Hepatocellular injury secondary to obstruction | | **Absence of hepatomegaly** | Mild only | Rules out primary hepatic disease | **Clinical Pearl:** In obstructive jaundice, ALP and GGT rise disproportionately to transaminases (cholestasis pattern); transaminases typically <4× upper limit of normal unless there is concurrent hepatocellular injury. ### Pathophysiology of Painless Jaundice 1. Tumor growth at pancreatic head compresses common bile duct gradually 2. Gradual obstruction → no acute inflammation → **no pain** 3. Progressive bilirubin accumulation → progressive jaundice 4. Bile stasis → pale/clay-colored stools, dark urine 5. Courvoisier sign develops (gallbladder distends because obstruction is distal to cystic duct) **Mnemonic: PAINLESS JAUNDICE = PANCREATIC CANCER** (until proven otherwise) - **P**rogressive onset - **A**bsence of pain - **I**ncreased ALP/GGT - **N**o fever - **L**ow transaminases - **E**xtrahepatic obstruction on imaging - **S**tone/stricture excluded by ultrasound - **S**onographic mass at pancreatic head ### Diagnostic Confirmation - **CT abdomen with contrast** (next step): assess resectability, metastases, vascular involvement - **ERCP with tissue sampling** or **EUS-FNA**: tissue diagnosis - **CA 19-9**: tumor marker (supportive, not diagnostic) **Warning:** Do NOT delay imaging or endoscopy in painless jaundice with imaging findings suggestive of malignancy — prognosis worsens with delay.