452. THE TREATMENT STRATEGY FOR RECURRENT OR UNRESECTABLE ESOPHAGEAL CANCER USING IMMUNE CHECKPOINT INHIBITORS

Abstract Background Cisplatine+5-FU (CF) was the first regimen for patients with recurrent or unresectable esophageal cancer in Japan. Nevertheless, the efficacy of the treatment was limited, and the prognosis of these patients was very poor. Recently, CF + Pembrolizumab (CF+Pmeb), CF + Nivolumab (CF+Nivo), Ipilimumab + Nivolumab (Ipi+Nivo) regimens were covered by the Japanese national health insurance system, and we get the option to use immune checkpoint inhibitor for advanced esophageal cancer. Methods Forty-six patients with recurrent or unresectable esophageal cancer treated with regimens including immune checkpoint inhibitors, were included in this study. We compared best overall response (BOR) among these three regimens. Besides, we also reviewed the validity of conversion surgery. Results Of the 46 patients, 17 and 29 patients were treated for recurrent and unresectable esophageal cancer, respectively. Among the patients with unresectable cancer, 3 patients were diagnosed with CR and 3 patients underwent conversion surgery, whose regimens were CF+Pmeb or CF+Nivo. We could achieve R0 resection in all 3 patients with conversion surgery. Postoperative complications grade 2 or more did not occur in these 3 patients. Recurrence has not been observed yet, though the follow-up periods were short (3 to 5 months). Among the patients with recurrence, 2 patients achieved a CR after treatment with CF+immuno checkpoint inhibitor. Conclusion Regimens with immune checkpoint inhibitors would be the hopeful treatment for advanced esophageal cancer patients. Conversion surgery would also play an important role in improving the prognosis.