Effectiveness of carboplatin vs cisplatin in lung cancer chemo-immunotherapy: A systematic review and meta-analysis

IntroductionChemo-immunotherapy (CT-IT) currently represents the standard therapy for both non-small (NSCLC) and small cell lung cancer (SCLC). However, the differential impact of platinum compounds on immunotherapy outcomes remains to be determined.MethodsA systematic review was conducted to identify randomized controlled trials (RCTs) of combinations of immune check-point inhibitors (ICIs) and platinum-based chemotherapy (CT), providing separate outcome data for carboplatin and cisplatin. Since no direct comparison between the two platinum compounds was reported, a network meta-analysis was performed. The primary endpoints were overall survival (OS) and progression-free survival (PFS) for advanced NSCLC and SCLC and event-free survival (EFS) for early-stage NSCLC.ResultsEleven RCTs including 6125 patients were analyzed. In extensive-stage SCLC (four trials, 2663 patients), a non-significant trend toward improved OS was observed with cisplatin-based regimens (HR: 0.92, 95% CI 0.72-1.18; I²=47%). In advanced NSCLC (four trials, 1948 patients), a non-significant trend toward improved PFS was observed with carboplatin-based regimens (cisplatin vs carboplatin HR: 1.11, 95% CI 0.89-1.39; I²=0%). In early-stage NSCLC (three trials, 1514 patients), no differences emerged in EFS between subgroups (p=0.65 fixed-effect; p=0.49 random-effects).ConclusionsOur analysis does not demonstrate a statistically significant difference between cisplatin- and carboplatin-based CT-IT in lung cancer, although stage- and histology-specific numerical trends were observed. Given the absence of head-to-head comparisons and the lack of disaggregated baseline data, these findings should be considered exploratory.