CEA levels and prognosis in colon carcinoma

This is a report of the post-operative follow-up of CEA titers in 16 patients with carcinoma of the colon and rectum. Our results differ from those previously reported in several respects. First, we rarely observed the return of elevated pre-operative CEA levels to normal within 14 days of curative resection. Second, we have found that CEA levels may be elevated for as long as 3 months in patients clinically free of disease before returning to normal. Third, some patients may maintain elevated CEA titers for 6 months following potentially curative resection without clinical evidence of disease. Finally, we have advanced a tentative hypothesis based on immunologic suppression of residual tumor growth to explain the discrepancy between our findings and those reported by others. These data suggest that failure to detect an early decline in CEA levels to normal may not imply a poor prognosis.