First-Line Platinum-Based Chemotherapy with Novel Systemic Agents for Unresectable or Metastatic Thymic Epithelial Tumors: A Systematic Review and Meta-Analysis

Background: Thymic epithelial tumors, including thymomas and thymic carcinomas (TC), are rare thoracic malignancies with poor prognosis in advanced stages. Platinum-based chemotherapy (CT) remains the first-line standard with limited efficacy. Novel systemic therapies, such as immune checkpoint inhibitors (ICIs) and antiangiogenic agents, have exhibited promise in refractory disease. Methods: statistic and Cochran's Q test. Results: Nine studies encompassing 208 patients were included, of which 93.7% had TC. The data set comprised five phase II trials and four retrospective cohorts. The pooled 12-month overall survival rate was 96.08% (95% confidence interval [CI]: 84.80-99.08), and 12-month progression-free survival was 56.68% (95% CI: 45.82-70.44). The median duration of response and median progression-free survival were 11.96 (95% CI: 6.32-22.64) months and 16.22 (95% CI: 10.30-25.52) months, respectively, with a pooled objective response rate of 57.69% (95% CI: 43.99-70.3). The objective response rate was 68.50% for antiangiogenic and 51.19% for ICIs combinations. Any-grade treatment-related adverse events occurred in 88.65%, grade 3 or higher in 30.22%, and grade 3 or higher immune-related adverse events in 11.62%, with treatment discontinuation in 13.55%. Conclusion: Platinum-based CT combined with ICIs or antiangiogenic agents exhibits promising efficacy and manageable toxicity, particularly in TC. Evidence in thymomas remains limited, and severe immune-related toxicity warrants caution. Randomized trials are needed for confirmation.