Data collection and response assessment
Medical records were examined and separated on clinical pathologic features and treatment histories. Data and follow-up records were updated as of March 1, 2021. The best response to PD-1 inhibitor-based therapy, defined as a complete or partial response and stable disease achieved at least once during therapy, was assessed using the RECIST v 1.1 criteria. The PFS was defined from the time of treatment initiation to clinical or radiographic progression or death. Adverse events (AEs) were graded by the National Cancer Institute Common Terminology Criteria for Adverse Events v5.0.