Serum CEA monitoring in the follow up of colorectal cancer patients with negative preoperative serum CEA

Thirty-nine patients with colorectal cancer and normal preoperative levels of carcinoembryonic antigen (CEA) were followed up with serial CEA determinations and with complete clinical and laboratory work-ups for the detection of tumor recurrence, for at least 1 yr after surgery. The same schedule for serum CEA assay and other clinical and laboratory tests was followed, for comparison, in 32 colorectal cancer patients with elevated preoperative serum CEA titers, and in whom surgery had been followed by a return to normal of the CEA values. In the follow-up group with negative preoperative serum CEA values, 66.7% of the patients had normal serum CEA titers, and 60% were free from symptoms of tumor recurrence after 1 yr from surgery. Whereas 28.2% of the patients of this group showed a steady rise of their serum CEA levels after periods ranging from 3-12 months from surgery; this serum CEA elevation preceded in nine of these patients other evidence of tumor recurrence by 3-5 months in the average. The above pattern was superimposable to that observed in the patients with positive preoperative serum CEA, about one third of whom exhibited a steady rise of serum CEA to abnormal values (as an early indicator of tumor recurrence) in the first year after surgery. The present results point out the relevant value of monitoring the serum CEA titers also in the postoperative follow-up of patients with normal preoperative serum CEA, since about one third of these patients may develop steadily rising serum CEA levels as an early indicator of tumor recurrence in the first year after surgical treatment.