LAUSR

BackgroundThe prognostic role of post-chemoradiotherapy (CRT) carcinoembryonic antigen (CEA) level is not clear. We evaluated the prognostic significance of post-CRT CEA level in patients with rectal cancer after preoperative CRT.MethodsWe reviewed 659 consecutive patients who underwent preoperative CRT and total mesorectal excision for non-metastatic rectal cancer. Patients were categorized into two groups according to post-CRT serum CEA level: low CEA (< 5 ng/mL) and high CEA (≥ 5 ng/mL).ResultsMedian post-CRT CEA level was 1.7 ng/mL (range, 0.1–207.0). A high post-CRT level was significantly associated with ypStage, ypT category, tumor regression grade, and pre-CRT CEA level. The 5-year overall survival rate of the 659 patients was 87.8% with a median follow-up period of 57.0 months (range, 1.4–176.4). When the post-CRT CEA groups were divided into groups according to pre-CRT CEA level, the 5-year overall survival rates were significantly different (P < 0.001 and P = 0.001, respectively). Post-CRT CEA level was an independent prognostic factor for overall survival. Multivariate analysis revealed that operation method, differentiation, perineural invasion, postoperative chemotherapy, tumor regression grade, and post-CRT CEA level were independent prognostic factors for overall survival.ConclusionThe level of serum CEA after preoperative CRT was an independent prognostic factor for overall survival in patients with rectal cancer.