A case of pseudomyxoma peritonei derived from the sigmoid colon

Abstract

A 79-year-old man was referred to our hospital with abdominal fullness, which had appeared in June 2007. Abdominal ultrasonography demonstrated massive ascites, and tumor marker CEA was elevated in serum (50.2ng/ml).
Colonoscopy revealed a type 1 tumor of the sigmoid colon, and pathological analysis of a biopsy sample suggested class 4, highly suspicious of well differentiated adenocarcinoma. Aspiration cytology of the ascites demonstrated the presence of mucin. We performed surgery under the tentative diagnosis of pseudomyxoma peritonei in September 2007.
The abdominal cavity was filled with many mucinous nodules, allowing a definite diagnosis of pseudomyxoma peritonei.
Appendectomy was performed because mucin adhered around the appendix, but there were no abnormal findings in its mucosa. We removed as many mucinous nodules as possible, and sigmoidectomy was also performed.
Histopathological examination of the resected specimen confirmed well differentiated adenocarcinoma with rich mucous lakes in the sigmoid colon tumor. The depth of tumor invasion was SE (exposed serosa), such that the sigmoid colon cancer was considered to be the origin of pseudomyxoma peritonei.
LV/UFT was used as adjuvant chemotherapy, and the patient's performance status has remained good to date. We report this case since the sigmoid colon is a rare origin of pseudomyxoma peritonei, which usually arises from the appendix.