Complete response and survival outcomes in patients with advanced cancer on immune checkpoint inhibitors.

To evaluate overall survival in advanced cancer patients who achieved complete response (CR) with immune checkpoint inhibitor (ICI) therapy. This retrospective study included patients with advanced unresectable or metastatic cancer who received at least one cycle of palliative-intent ICI. Best overall response was used to define response groups. 21 (7%) of 322 patients achieved CR. Multivariate analysis demonstrated that CR was independently associated with better overall survival compared with disease progression (hazard ratio: 0.012; 95% CI: 0.002-0.090) and stable disease (hazard ratio: 0.063; 95% CI: 0.009-0.464) as well as a nonsignificant trend toward better overall survival compared with partial response (hazard ratio: 0.169; 95% CI: 0.023-1.252) regardless of cancer type, ICI regimen or ICI line. Patients who achieved CR had longer survival compared with patients who did not achieve CR.