On barium enema, 'apple-core' lesion with shouldering (abrupt transition between normal and abnormal mucosa) is most characteristic of:
- A Carcinoma of the colon ✓
- B Crohn's colitis
- C Ischaemic colitis
- D Diverticular stricture
Correct answer: A. Carcinoma of the colon
Explanation
The apple-core (napkin-ring) lesion on barium enema represents annular carcinoma of the colon, where circumferential tumor growth produces abrupt mucosal destruction ('shouldering') at both ends of the lesion, creating a short irregular narrowing. Crohn's colitis produces a 'cobblestone' pattern, skip lesions, and string sign but rarely true apple-core. Ischaemic colitis produces 'thumb-printing' (pseudopolyposis from submucosal edema). Diverticular strictures show diverticula adjacent to the narrowing and a longer gradual transition.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.