Cytologic findings in signet-ring adenocarcinoma of the large bowel. A case report.

Signet-ring adenocarcinoma of the large bowel is an uncommon tumor with distinctive gross anatomic, radiologic and histologic features. A case in a 34-year-old man is presented. Because of the unusual appearance of the bowel at colonoscopy, diagnostic cytologic smears were taken. The patient subsequently underwent resection of this tumor but died within 20 months of metastatic disease. The histologic and cytologic features are described; the cytologic findings do not appear to have been previously reported.