Which histologic type of colonic polyp greater than 1 cm has the greatest malignant potential?

Which histologic type of colonic polyp greater than 1 cm has the greatest malignant potential?

• A. Hyperplastic polyp
• B. Villous adenoma
• C. Inflammatory polyp
• D. Tubular adenoma

Answer: (B)

Colonic polyp cancer risk rises with both size and certain histologic patterns. Hyperplastic polyps are typically benign with minimal malignant potential, and inflammatory polyps reflect an inflammatory process rather than a premalignant lesion. Among adenomas, the risk increases as the architecture becomes more villous and less tubular; villous adenomas carry the highest risk, especially when large. A villous adenoma over 1 cm is most likely to harbor or develop high-grade dysplasia or cancer, reflecting the adenoma–carcinoma sequence.

Colonic polyp cancer risk rises with both size and certain histologic patterns. Hyperplastic polyps are typically benign with minimal malignant potential, and inflammatory polyps reflect an inflammatory process rather than a premalignant lesion. Among adenomas, the risk increases as the architecture becomes more villous and less tubular; villous adenomas carry the highest risk, especially when large. A villous adenoma over 1 cm is most likely to harbor or develop high-grade dysplasia or cancer, reflecting the adenoma–carcinoma sequence.