Postsurgical Surveillance of Colon Cancer

Abstract
Objective This study is the first to examine the relative and absolute costs of physician examination, carcinoembryonic antigen (CEA) assessment, chest x-ray, and colonoscopy in detecting recurrent disease in patients who have undergone surgical resection for primary colon carcinoma. Methods Of the 1356 Eastern Cooperative Oncology Group patients in Intergroup Protocol 0089 who underwent surgical resection for Dukes' B2 and C colon carcinoma, 421 patients who developed recurrent disease were reviewed. Follow-up testing was performed according to protocol guidelines, with the cost of each test equal to 1995 Medicare reimbursement. Follow-up was defined as the time to recurrence for the 421 patients in whom disease recurred (mean 18.6 months) or up to 5 years for the additional 930 patients in whom disease did not recur (mean 38.6 months). Patients were divided into three categories: nonrecurrent, recurrent but not resectable, and recurrent but resectable with curative intent. The estimated mean cost of each test in detecting group 3 (recurrent but resectable) patients was calculated. Results Of the 421 patients who developed recurrent disease, 96 underwent surgical resection of their disease with curative intent (group 3). For group 3 patients, the first indication of recurrent disease was CEA testing (30), chest x-ray (12), colonoscopy (14), and other (40). Of the 40 "other" patients, 24 presented with symptoms. Routine physician examination, however, failed to identify a single resectable recurrence, and the total cost for physician examination was $418,615. The detection rate for CEA testing was 2.2%, the total cost was $170,880, and the cost per recurrence was $5,696. The detection rate for chest x-ray was 0.9%, the total cost was $120,934, and the cost per recurrence was $10,078. The detection rate of colonoscopy was 1%, the total cost was $641,344, and the cost per recurrence was $45,810. Conclusions CEA measurement was the most cost-effective test in detecting potentially curable recurrent disease. Physician visits were useful only in the evaluation of symptoms; a routine physician examination had no added benefit.