Clinical utility of tumor marker cutoff ratio and a combination scoring system of preoperative carcinoembryonic antigen, carbohydrate antigen 19-9, carbohydrate antigen 72-4 levels in gastric cancer

PURPOSE The present study is to investigate the clinical utility of tumor marker cutoff ratio (TMR) and develop a TMR combination scoring system based on preoperative tumor marker (TM) levels to prognosis prediction in gastric cancer. METHODS We include 1,142 patients for whom two or more TMs were measured and who underwent radical gastrectomy between 1990 and 2003. RESULTS Five-year risk of recurrence (5 YRR) for carcinoembryonic antigen (CEA) TMRs were 18.3%, 29.8%, 61.4% for TMR < 1.0, 1.0 ≤ TMR < 2.0, TMR ≥ 2.0 respectively. 5 YRR for carbohydrate antigen 19-9 (CA 19-9) TMR were 19.7%, 35.6%, 58.4% for TMR < 1.0, 1.0 ≤ TMR < 3.0, TMR ≥ 3.0, respectively. 5 YRR for carbohydrate antigen 72-4 (CA 72-4) TMR were 15.2% and 33.6% for TMR < 1.0 and TMR ≥ 1.0, respectively. We defined high TMR (TMR ≥ 2.0 for CEA, TMR ≥ 3.0 for CA19-9), low TMR (1.0 ≤ TMR < 2 for CEA, 1.0 ≤ TMR < 3.0 for CA 19-9 and 1.0 ≤ TMR for CA72-4) and negative TMR (TMR < 1.0 for all TMs). A TMR combination scoring system was devised with negative scored as zero points, low as 1 and high as 2 for each TMR. TMR scores were divided into four categories (score 0, 1, 2, 3 and above) based on the calculated TMR score and 5 YRR were found to be 12.8%, 23.9%, 45.5%, and 68.3%, respectively (P < 0.05). Multivariate analysis showed that our scoring system was a significant independent prognostic factor. CONCLUSION Preoperative TMRs such as CEA, CA 19-9, and CA 72-4 show a correlation with prognosis and the TMR combination scoring system could be a useful tool for the prediction of prognosis in gastric cancer.