Prognostic Factors Of Patients With Thymic Carcinoma After Surgery

Objective: Thymic tumor could originate from a variety of tissues. Thymic carcinoma drived from epithelial cells of thymus, with low incidence, is a rare mediastinal malignant tumor. But its incidence increases in recent years. Thymic carcinoma is similar to other thymic tumors in aspects of tumor location, radiological characteristics and clinic symptoms, but histologic behavior of thymic carcinoma is significantly different from the other thymic tumors, which shows highly aggressive malignancy. The diagnosis and treatment of thymic carcinoma are different from other thymic tumors. There is still a lot of controversy in the mode and efficacy of treatment because of limited clinic experience. This paper analyzes the clinical features of thymic carcinoma and further researches the prognostic factors to improve the level of the diagnosis and treatment of thymic carcinoma. We analyze the prognostic significance of undetermined factors to predict the survival of patients after surgery.Methods:We reviewed 351 cases of thymic epithelial tumor treated with surgery at a single institution in China from 1994 to 2013. A total of 58 patients were histopathologically reconfirmed as having thymic carcinoma. Clinicopathological characteristics and treatment modalities were reviewed. During the follow-up, with a median of 65.8 months, survival time was analyzed using the Kaplan-Meier method. Univariate and multivariate analysis were performed to identify prognostic factors.Results:The overall 3-,5-, and 10-year survival rate was 69.0,43.1, and 12.1%, respectively. The Log-rank test revealed that Masaoka stage (p < 0.001), histology group (p < 0.001), completeness of the resection (p < 0.001), great vessel invasion (p < 0.001), and presence of symptoms (p < 0.05) were significant prognostic factors in all patients. However, tumor size (p = 0.086), age (p = 0.677), sex (p = 0.706), smoking (p = 0.065), and alcohol (p = 0.875) were not prognostic factors. ACox proportional hazards regression model showed that Masaoka stage (hazard ratio = 15.640, p< 0.001) and completeness of the resection (hazard ratio = 18.303, p< 0.001) were the only independent prognostic factors.Conclusions:The Masaoka stage and completeness of the resection were independent prognostic factors that predicted long-term survival of patients with thymic carcinoma treated with surgery.