Morphogenesis and possible precursor lesions of invasive carcinoma of the papilla of Vater: epithelial dysplasia and adenoma.

Surgical specimens from 58 invasive carcinomas of the papilla of Vater were studied histomorphologically. Tubular or villous adenomas, adenomatous residues, and microadenomas were found in the vicinity of the carcinomas in 91.4 per cent of the cases; moderate or severe epithelial dysplasia in adenomatous structures or in surface and ductal epithelium was present in 81 per cent of the cases. The results of the present histomorphologic study support the hypothesis that invasive carcinomas arise from pre-existing mucosal lesions, such as adenoma or dysplasia.