Biopsy appearances easily mistaken for malignancy in gastrointestinal endoscopy

A series of 10 cases is described which were characterized by the occurrence, in gastrointestinal endoscopic biopsies, of benign lesions which bore a close resemblance to malignancy. In three cases an erroneous diagnosis of carcinoma was made and major resections were performed unnecessarily. The lesions fall into two histological types, one of which is seen only in gastric biopsies and the other at any level of the gastrointestinal tract. The histopathology of these lesions is described in detail.