Colonic perforation resulting from ingested chicken bone revealing previously undiagnosed colonic adenocarcinoma: report of a case and review of literature.

An 86 year old male with a four-day history of nonspecific gastrointestinal symptoms was found on colonoscopy to have evidence of sigmoid colon obstruction and possible perforation. Emergent operative exploration revealed diffuse peritonitis, sigmoid perforation, adjacent dense adhesions, and a foreign body protruding through the perforated area. Pathologic examination showed the foreign body to be a sliver of bone consistent with chicken bone and the sigmoid subacute perforation to be associated distally with a circumferential ulcerated obstructing mass, microscopically seen to be transmurally infiltrating adenocarcinoma, signet-ring cell type. There was extensive acute and organizing peritonitis, 100% Escherichia coli was cultured from peritoneal fluid, and the patient died two days postoperatively with sepsis and hypotension. This appears to be the fifth reported case of colonic perforation resulting from foreign body perforation due to previously undiagnosed adenocarcinoma. The four previously reported cases were all deeply invasive adenocarcinoma of sigmoid colon, and the foreign bodies included three chicken/poultry bones and a metallic staple. These five cases are highly unusual examples of a potentially lethal malignant neoplasm being clinically revealed by a usually (but not always) innocuous event, the ingestion of a small foreign body.