Background. Thymic carcinoma is a rare, indolent, and invasive cancer. This study investigated the treatment results of thymic carcinoma and clinical prognostic factors.Methods. From June 1988 to January 2002, 38 patients were enrolled in this study with the diagnosis of thymic carcinoma in the Cheng-Kung University Hospital based on Rosai's and Muller-Hermelink's classification. Clinical and pathologic data were retrospectively reviewed. Survival analysis was performed using the KaplanMeier, log rank, and Wilcoxon tests. Statistical significance was defined as p < 0.05.Results. Pathology revealed 14 poorly differentiated, 6 moderately differentiated, and 8 well-differentiated squamous cell carcinomas; 8 lymphoepithelioma-like carcinomas; and 2 other carcinomas. Pathologic staging using the Masaoka system included 6 stage II, 23 stage III, and 9 stage IV patients. Six biopsies, five debulkings,