The Use of Preoperative Plasma CEA Levels for the Stratification of Patients After Curative Resection of Colorectal Cancers

Abstract
One hundred forty-five patients with colorectal cancer were analyzed in order to correlate the preoperative plasma carcinoembryonic antigen (CEA) levels with the sites and times of disease recurrence. The median follow-up periods of these patients was 50 months (range 36–72 months). Twenty-one patients were found to have metastases at the time of their operation. None of the seven patients whose primary tumors were classified as Dukes/Kirklin A have had tumor recurrence. Seventeen per cent of the patients with Dukes/Kirklin B tumors have had tumor recurrences, and 63% of the patients with Dukes/Kirklin C colorectal primary tumors have had tumor recurrence. No correlation was found between preoperative CEA values and subsequent risk of tumor recurrence or times to recurrence among the patients with Dukes/Kirklin B colorectal primary cancers. In Dukes/Kirklin C patients, however, elevated preoperative CEA values predicted a higher risk of tumor recurrence. Ninety per cent of the patients (19/21) with preoperative CEA levels greater than 5.0 ng/ml have had relapses, with a median time of 17 months before disease recurrence. Only 39% (9/23) of the patients with Dukes/Kirklin C lesions and CEA levels less than 5 ng/ml have had relapses and there is insufficient follow-up data as yet to determine the median survival time. If those patients whose Dukes/Kirklin C primary tumors were poorly differentiated on histologic examination are excluded, the contrast between patients having CEA levels greater than 5.0 ng/ml and those having CEA levels less than 5 ng/ml is even more marked. Sixteen of the 18 remaining patients whose CEA levels were greater than 5.0 ng/ml prior to curative resection have had relapses as compared with only three of 15 patients whose preoperative CEA values were less than 5. We conclude, therefore, that CEA is an important factor in stratifying patients after curative resection of their Dukes/Kirklin C colorectal tumors.