Four Percent of Patients Undergoing Colorectal Cancer Surgery may have Synchronous Appendiceal Neoplasia

Abstract

An individual with colorectal cancer has a 3 percent risk of synchronous colonic neoplasia and further 2 to 3 percent risk of metachronous cancer, a risk that has prompted colonic surveillance. The appendix has a similar mucosal pattern to the colon and it has been hypothesized that appendicular adenocarcinoma may account for 1 percent of all colorectal malignancies. A special interest of the senior author in appendiceal and rectal cancer has prompted routine removal of the appendix in all cases undergoing surgery for colorectal cancer. Consecutive patients undergoing left colectomy or anterior resection for colorectal cancer had coincidental appendectomy with the specimen pathologically analyzed. A retrospective review of the case notes and histopathology was performed. Data also were collected for patients who had right hemicolectomy for colonic carcinoma. In total, 169 patients under the care of a single surgeon had colorectal cancer resection between April 2002 and April 2005: 63 patients had right hemicolectomy, 29 had left hemicolectomy, and 77 had rectal cancer resection. Seven of 169 appendices had abnormalities: 3 mucinous cystadenomas, 2 cystadenocarcinomas, 1 carcinoid tumor, and 1 villous adenoma. Patients having colorectal cancer resection for adenocarcinoma should have appendicectomy performed. Synchronous pathology was found in 4.1 percent in this series. Metachronous neoplasia is a risk in the retained appendix in patients with colorectal cancer. Routine postoperative surveillance cannot assess the appendiceal mucosa, so there is little justification for not taking the opportunity to eliminate the possibility of future appendicitis or neoplasia.