Serum carcino-embryonic antigen (CEA) and its possible use as tumor marker for secondary tumors in urinary intestinal reservoirs

ObjectivesSerum carcino-embryonic antigen (CEA) has become a useful tumor marker in patients with colorectal adenocarcinoma. Patients who undergo uroenteric reconstruction, such as urinary diversion (UD), have an increased risk of developing malignant changes in their UD. We compared serum CEA levels in patients with different types of UD, evaluating long-term CEA changes and assessing its potential for use as a tumor marker of malignant transformation in the UD.Materials and methodsSerum CEA was evaluated 3 to 122 months after surgery in 177 patients with different types of UD and retrospectively analyzed. The normal range for CEA was 0.2–3.4 μg/l. No patient had a history of colorectal cancer.ResultsA total of 443 CEA samples from 177 patients were evaluated. CEA was elevated (up to 32 μg/l) in 122 samples (27.5%) from 59 patients (33.3%). Patients with Mainz Pouch II had significantly higher CEA levels (P = 0.037) than patients with other forms of UD. CEA levels increased significantly in the study population during follow-up (P = 0.0000007). Five of the patients (2.8%) developed a secondary neoplasm, 4 of whom had elevated CEA. Three neoplasms (urothelial cancer) were located outside the UD. Only 2 tumors were actually located in the UD: an urothelial cancer at the uretero-colonic anastomosis of the UD with normal CEA levels, and a colonic adenoma at the bottom of the UD with elevated CEA levels. No patient had adenocarcinoma in the UD.ConclusionElevated serum CEA is a common finding in patients with UD using bowel segments (33.3%), especially in patients with rectal reservoirs. Serum CEA has a tendency to increase over time in patients with UD but is not a valuable marker of secondary neoplasms in these patients.