The value of routine serum carcino-embryonic antigen measurement and computed tomography in the surveillance of patients after adjuvant chemotherapy for colorectal cancer.

Abstract

This analysis aims to evaluate routine carcino-embryonic antigen (CEA) and computed tomography (CT) of thorax, abdomen, and pelvis as part of protocol-specified follow-up policy for colorectal cancer (CRC). Patients with resected stage II and III CRC were randomly assigned to bolus fluorouracil/leucovorin or protracted venous infusion fluorouracil. Following completion of chemotherapy, patients were seen in clinic at regular intervals for 5 years. CEA was measured at each clinic visit, and CT of thorax, abdomen, and pelvis was performed at 12 and 24 months after commencement of chemotherapy. Between 1993 and 1999, 530 patients were recruited. The median follow-up was 5.6 years. Disease relapses were observed in 154 patients. Relapses were detected by symptoms (n = 65), CEA (n = 45), CT (n = 49), and others (n = 9). Fourteen patients, whose relapses were detected by CT, had a concomitant elevation of CEA and were included in both groups. The CT-detected group had a better survival compared with the symptomatic group from the time of relapse (P =.0046). Thirty-three patients (21%) proceeded to potentially curative surgery for relapse and enjoyed a better survival than those who did not (P <.00001). For patients who underwent hepatic or pulmonary metastatic resection, 13 (26.5%) were in the CT group, eight (17.8%) in the CEA group, and only two (3.1%) in the symptomatic group (CT v symptomatic, P <.001; CEA v symptomatic, P =.015). Surveillance CT and CEA are valuable components of postoperative follow-up in stage II and III colorectal cancer.