Colonoscopy in a 60-year-old man identifies three types of epithelial polyps in different patients: a tubular adenoma, a tubulovillous adenoma, and a villous adenoma. Which statement about their malignant potential is correct?

• A Villous architecture confers the highest malignant potential ✓
• B Tubular adenoma carries the highest risk of containing invasive carcinoma
• C All three carry identical risk once size exceeds 1 cm
• D Malignant potential depends only on the degree of dysplasia, not architecture

Explanation

Malignant risk in adenomas rises with villous component, larger size, and severity of dysplasia. Pure villous adenomas have the highest rate of harboring invasive carcinoma, roughly 30 to 40 percent when large, compared with about 5 percent for purely tubular adenomas. Tubulovillous lesions are intermediate. Architecture matters independently of dysplasia grade, so option D is incomplete and option B reverses the true ranking.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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