Prognostic value of carcinoembryonic antigen level in rectal cancer treated with neoadjuvant chemoradiotherapy

Abstract

Background: The purpose of this study was to identify clinical and pathological parameters to improve prediction of disease-free survival (DFS) and overall survival (OS) in patients treated with neoadjuvant chemoradiotherapy for rectal cancer.

Methods: Between July 1995 and May 2007, 148 patients with primary rectal adenocarcinoma received neoadjuvant chemoradiotherapy followed by mesorectal excision. Preoperative treatment included various protocols, UFT and leucovorin (28%) and oxaliplatin-based chemotherapy (72%). Clinical and pathological variables were evaluated in relation to patient outcomes.

Results: Thirteen percent of patients achieved a complete pathologic response. No response or minimal response as defined by Dworak (Tumor Regression Grade 0/1) was observed in 30 patients (20%). At a median follow-up of 37 months, the 3-year DFS and OS were 64% and 83%, respectively. Pre-treatment serum carcinoembryonic antigen (CEA) level </= 2.5 ng/ml was associated with higher DFS (74 vs. 53%; p = 0.018), higher complete pathologic responses (21 vs. 9%; p = 0.05), and less recurrences (24 vs. 44%; p = 0.014).

Conclusion: The data suggest that a CEA level </= 2.5 ng/ml might be a predictor not only of tumor response, as has been suggested before, but also of DFS. This finding could be useful in the future to predict individual risk and to develop more aggressive or alternative strategies.