Therapy for thymic epithelial tumors.

Thymoma is the most common tumor of the anterior mediastinum. This tumor is associated with unique paraneoplastic syndromes. The rarity of this tumor has somewhat obscured the optimal treatment for this disease. The World Health Organization classification system, which published in 1999, appears to be an advance in our understanding of thymoma. The Masaoka classification is now the most widely accepted and is an excellent predictor of the prognosis of thymoma. Now the International Thymic Malignancy Interest Group is currently engaged in the development of a validated formal TNM classification system for thymic malignancies. The optimal treatment of thymoma is performed according to its clinical stage. Surgery remains the mainstay of treatment for thymic epithelial tumors. Minimally invasive surgery including thoracoscopic surgery and robotic surgery for stage I and II thymomas is increasing now. The value of postoperative radiotherapy in completely resected stage II or III tumors is questionable. As thymomas have a moderate response rate to chemotherapy or radiotherapy, multimodality therapy involving surgery, chemotherapy and radiotherapy appears to increase the rate of complete resection and survival in the advanced (stage III and IV) thymomas.