Surgery for invasive primary mediastinal tumors

Background. There have been few reports on results after extended radical resection for primary mediastinal tumors invading neighboring organs. Methods. A retrospective analysis of 89 patients who underwent total or subtotal resection of a primary mediastinal tumor with resection of at least part of an adjacent structure between 1979 and 1995 was performed. Clinical data were collected from the medical records. Results. There were 35 invasive thymomas, 12 thymic carcinomas, 17 germ cell tumors, 16 lymphomas, 3 neurogenic tumors, 3 thyroid carcinomas, 2 radiation-induced sarcomas, and 1 mediastinal mesothelioma. The tumor was located in the anterior mediastinum in 74% of patients. Residual masses after chemotherapy were excised in 14 patients with germ cell tumor and 8 with lymphoma. A median sternotomy was the most frequently used approach (79% of patients). Total resection was achieved in 79% and significantly improved survival (p < 0.01). Adjacent resected structures included 38 phrenic nerves, 21 superior venae cavae, 16 upper lobes, and 13 innominate veins, in 5 patients, a pneumonectomy was required. The complication rate was 17% and the mortality rate, 6%. With follow-up available for 86 patients, the overall 5-year survival rate was 69% for patients with thymoma, 42% for patients with thymic carcinoma, 48% for patients with germ cell tumor, and 83% for patients with lymphoma. Conclusions. Malignant mediastinal tumors can be safely resected even if they have invaded other mediastinal structures. Complete resection is important to achieve satisfactory long-term survival. A median sternotomy is an excellent approach, and a preoperative diagnosis by biopsy is desirable. Residual masses after chemotherapy for lymphoma or germ cell tumor should be resected. Extensive resection without a preoperative diagnosis is not indicated.