Sequential carcinoembryonic antigen levels. A predictor of response and relapse in combination chemotherapy of advanced gastrointestinal cancer

Abstract

Serial determinations of plasma carcinoembryonic antigen (CEA) levels were assayed for 34 patients with advanced gastrointestinal cancer undergoing 5-fluorouracil and mitomycin C combination chemotherapy. 21 patients (62%) had an objective response and the CEA level was decreased in 12. After chemotherapy was initiated a rise in CEA level occurred on the average 6.5 months later, while the mean time to clinical relapse was 8 months. 5 patients (15%) had stable disease; the CEA level was decreased in 2. In 8 patients (24%) with progressive disease, the mean time for a rising CEA level was 3 months. In our view, a change in the CEA level reflects the effectiveness of combination chemotherapy in patients with advanced gastrointestinal cancer.