Treatment of malignant thymoma

The present review reports findings in the field of epithelial tumors originating from the thymus from the past year and discusses these findings in the context of the literature.

Epithelial tumors of the thymus are relatively common tumors of the anterior superior mediastinum. Thymomas are usually slowly growing tumors, and their prognosis depends on the macroscopic and microscopic invasion of surrounding tissues. Thymic carcinomas are more aggressive and less common tumors than thymomas and have been increasing in frequency in recent years. Surgery is the mainstay treatment of thymic malignancies, and complete resection represents the best prognostic factor in this disease. Postoperative radiotherapy may be indicated in tumors with invasion of surrounding tissues, but it is controversial in early-stage thymomas. Combination chemotherapy has been employed in several small studies and in advanced disease has been demonstrated to produce a 50-80% objective response rate. Neoadjuvant chemotherapy or external beam radiotherapy have been used with success in patients with tumors that are not readily resectable. Novel antiproliferative systemic agents are being investigated, based on a better understanding of the biology of these tumors.

A better understanding of the clinical behavior of thymomas versus thymic carcinomas and systemic therapies targeted to biologically validated targets in these diseases will help improve efficacy of treatment.