Alpha-fetoprotein for gastric cancer staging: An essential or redundant tumor marker?

Background/Aim: This study was designed to clarify the value of routine alpha-fetoprotein (AFP) testing for patients with gastric cancer (GC). Patients and Methods: A total of 905 patients with newly diagnosed GC and available pretreatment carcinoembryonic antigen (CEA), cancer-related antigen 19-9 (CA19-9), and AFP data from 2010 to 2016 were collected for comparison of tumor stage and survival. Results: In total, 139 patients (15.4%), 155 patients (17.1%), and 27 patients (3.0%) had elevated CEA, CA19-9, and AFP levels, respectively. The c-index values of elevated AFP levels in predicting stage IV disease and the 1-year mortality rate were 0.564 (95%CI=0.520-0.608) and 0.594 (95%CI=0.553-0.635), respectively, which were significantly lower than those of CEA (0.673 and 0.665) and CA19-9 (0.619 and 0.618). Conclusion: Elevated AFP is rare in patients with newly diagnosed GC. Routine AFP sampling would not provide a higher survival prediction in GC patients than CEA or CA19-9.