Prognostic factors of second-line nivolumab monotherapy for unresectable or metastatic esophageal cancer: a multi-institutional cohort study for 184 cases.

Our study demonstrated that the real-world outcomes of second-line nivolumab monotherapy were comparable to those of previous randomized clinical trials in terms of tumor response, safety, and long-term survival. Furthermore, a good performance status and low C-reactive protein levels may identify patients who are likely to benefit from therapy. Third-line chemotherapy after nivolumab treatment may have an enhanced effect; however, further prospective studies are required to confirm this finding.