Optimal first‐line treatment for advanced thymic carcinoma

BACKGROUND: Thymic carcinomas (TCs) are rare aggressive tumors with no standard first‐line treatment. This study was conducted to determine the optimal chemotherapy regimen for advanced TC. METHODS: This retrospective study included 67 patients treated for stage IV TC in 2006–2015. The primary endpoints were the objective response rate (ORR) and progression‐free survival (PFS) with different chemotherapy regimens. Multivariate Cox regression analysis was used to identify factors associated with PFS, including metastatic status, radiotherapy post‐chemotherapy, primary lesion resection before chemotherapy, and chemotherapy regimen. RESULTS: A total of 36 patients received a paclitaxel‐platinum regimen, 31 received a gemcitabine‐platinum regimen, 14 underwent primary lesion resection, and 33 underwent radiotherapy. ORR was 31% (11/36) and 29% (9/31) in the paclitaxel‐platinum and gemcitabine‐platinum groups, respectively (P = 0.890). Median PFS, one‐year PFS rate, and two‐year PFS rate were 7.0 months, 26%, and 6% with paclitaxel‐platinum treatment and 12 months, 48%, and 24% with gemcitabine‐platinum treatment (log‐rank P = 0.030). Median PFS, one‐year PFS rate, and two‐year PFS rate were 18.0 months, 57%, and 33% with surgical resection and 7.3 months, 31%, and 7% without resection (log‐rank P = 0.030). Median PFS, one‐year PFS rate, and two‐year PFS rate were 13.0 months, 52%, and 20% with radiotherapy and 4.3 months, 22%, and 7% without radiotherapy (log‐rank P = 0.001). In multivariate analysis, metastatic status (hazard ratio [HR], 0.33, P = 0.004), surgical resection (HR, 0.32; P = 0.004), and radiotherapy (HR, 0.32; P < 0.001) were associated with superior PFS. CONCLUSIONS: Both gemcitabine‐platinum and paclitaxel‐platinum regimens were efficacious for advanced TC. Primary lesion resection and radiotherapy may also benefit selected patients.