Colonic carcinoma presenting as an appendiceal abscess in a young woman.

A 38-year-old woman with stage T4N0M0 adenocarcinoma of the cecum presented with what seemed to be an appendiceal abscess. She had a 10-month history of intermittent abdominal pain in the right lower quadrant. Initial laparotomy revealed an abscess in that quadrant. The abscess was drained. A mass in the cecum, associated with dense fibrous tissue and abscess formation, was found on subsequent surgical exploration. Pathological examination revealed a well-differentiated mucinous adenocarcinoma of the cecum with transmural invasion. The lesion had replaced most of the vermiform appendix and was associated with a periappendiceal abscess. Colonic carcinoma masquerading as acute appendicitis or an appendiceal abscess is a well-recognized entity in the elderly but may be overlooked in younger patients because malignant disease is not suspected.