P-0213 Surveillance With Serial Serum Carcinoembryonic Levels Detect Colorectal Cancer Recurrences in Patients Who are Initial Nonsecretors

Abstract

ABSTRACT Introduction Serum carcinoembryonic antigen (CEA) levels, elevated in a subgroup of patients with colorectal cancer (CRC) at presentation, are serially followed as part of recommended surveillance after initial resection. The value of following serial CEA levels in patients who initially present with less than or normal levels of CEA (nonsecretors) is controversial. This study sought to determine the use of follow-up CEA levels in nonsecretors. Methods A retrospective review was performed of patients with resected Stage I, II, and III CRC. We excluded patients who did not have a pretreatment CEA level, at least two follow-up CEA levels, or in whom CEA levels did not normalize after resection. The patients were grouped by initial CEA values: CEA 5 ng/mL or less (nonsecretors) and CEA 5+ng/mL: (secretors). Results We identified 186 patients with CRC; 146 were initial nonsecretors. We identified 22 patients with recurrent colorectal cancer; 6 were secretors and 16 patients were nonsecretors. In the secretors group, CEA was elevated with recurrence in four (66%) of the patients. In the nonsecretors, CEA was elevated with recurrence in eight (50%) of the patients. Conclusion In summary, many recurrences of CRC are marked by an elevation of CEA regardless of whether the patients initially presented as secretors or nonsecretors.