Possible Predictive Markers of Immunotherapy in Esophageal Cancer: Retrospective Analysis of a Randomized Study

Abstract

The aim of this report is to evaluate retrospectively the data from a prospective randomized study of 158 esophageal cancer patients who actually completed therapy with protein-bound polysaccharide P (PSK) and the 5-year survivals with and without raised α1-antichymotrypsin and sialic acid levels to determine the value of these parameters in predicting effectiveness of immunotherapy.There was a significant difference in survival between the patients with and without PSK therapy. The survival of the radiochemotherapy plus PSK group treated for >3 months was significantly better than that of the radiochemotherapy group. Among the patients with abnormal levels of α1-antichymotrypsin and sialic acid, those who received PSK may have a significantly better survival than those without PSK.These results indicate that the preoperative serum levels of α1-antichymotrypsin and sialic acid may possibly predict the effectiveness of immunotherapy using PSK.