The Significance of Papillary Features in Polyps of the Large Intestine

Abstract

Six hundred sixty-two polypoid lesions of the large intestine were classified as adenomas, papillomas, mixed lesions (adenomatous and papillary features), or hyperplastic polyps. Carcinoma was found in 48% of papillomas, 18% of mixed lesions, and 1% of adenomas. Among the hyperplastic polyps, three (5%) contained a mixture of hyperplastic and carcinomatous glands. Eighty per cent of the carcinomas were superficial and 20% were invasive. Metastases occurred in one third of the invasive carcinomas and in none of the superficial carcinomas. The findings suggest that the presence of a papillary growth pattern in colonic polyps heralds an increased malignant potential. The role of inconsistent terminology and definitions in the controversy regarding the malignant potential of colonic polyps is discussed.