Postsurgical Surveillance of Colon Cancer

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.