Prognostic value of early postoperative tumor marker response in gastric cancer

Background: The clinical usefulness of tumor markers as predictors of treatment outcome in patients with stomach cancer after radical gastrectomy has been poorly defined. The purpose of this study was to evaluate a comprehensive understanding of the impact of early postoperative tumor marker normalization on survival after gastrectomy. Methods: Between January 2001 and December 2007, we enrolled 206 patients who had received radical gastrectomy as an initial treatment and had elevated carcinoembryonic antigen (CEA) (>5 ng/mL) or carbohydrate antigen (CA) 19-9 (>37 U/mL) levels. Early tumor marker response was defined as a normalization of preoperative CEA or CA19-9 values 1-2 months after gastrectomy. Results: The mean patient age was 61 years (range 29-84 years), and 139 patients (67.5 %) were male. Early tumor marker response was identified in 150 of 206 (72.8 %) patients. Of the patients, 49 (23.8 %), 41 (19.9 %), and 116 (56.4 %) were stages I, II, and III, respectively, according to the seventh edition of the American Joint Commission on Cancer (AJCC) staging system. Both disease-free survival (DFS) and overall survival (OS) were significantly longer in patients with tumor marker response compared with nonresponse (61.5 vs. 37.6 months; P = 0.010 and 71.3 vs. 50.9 months; P = 0.008, respectively). Multivariate analyses showed that high CA19-9 level, early tumor marker response, and tumor, node, metastasis classification system stage were independent predictors of DFS and OS (P < 0.05). Conclusions: Early CEA or CA19-9 normalization after radical gastrectomy is a strong prognostic factor for gastric cancer, especially in patients with high preoperative levels of tumor markers.