OBJECTIVE The purpose of this study was to evaluate the impact of cisplatin, doxorubicin, and cyclophosphamide (PAC) in patients with advanced thymoma with respect to response rate, duration of remission, and overall survival. METHODS Assessable patients with thymoma (n = 29) or thymic carcinoma (n = 1) with metastatic or locally progressive recurrent disease following radiotherapy were treated with intravenous cisplatin (50 mg/m2), doxorubicin (50 mg/m2), and cyclophosphamide (500 mg/m2) with normal saline hydration. Courses were repeated every 3 weeks for a maximum of eight cycles of therapy. RESULTS Toxicity, which was primarily hematologic, was mild, with only one patient developing a fever associated with neutropenia. Three complete responses (CRs) and 12 partial responses (PRs) were observed (CR+PR rate, 50%; 95% confidence interval, 31.3% to 68.7%). Ten patients had stable disease. The median duration of response was 11.8 months (range, 0.9 to 70.5+), the time to treatment failure 18.4 months (range, 0.8 to 91.9+), and median survival time 37.7 months (range, 2 to 91.9+). CONCLUSIONS This trial demonstrates that objective response rates and prolonged survival can be achieved in patients with advanced thymoma.