To establish the distribution of malignant mediastinal tumors according to histological structure, surgery, location and age.
Between 1992 and 2002, 71 patients were operated on for 54 anterior, 6 middle and 11 posterior mediastinal tumors. 17 of the 54 tumors were malignant. 16 (94%) of the malignant tumors were located in the anterior, and 1 (6%) in the posterior mediastinum. They were 10 females and 7 males; average age 42.6 years (13-68). The surgical approaches were 8 median sternotomies, 8 posterolateral thoracotomies, and for a dumb-bell tumor it was a combined exposure (posterior laminectomy, followed by left posterolateral thoracotomy). In 5 cases, the tumor could be removed only with extended resection (1 lobectomy with chest wall resection, 2 wedge resections, 2 pericardial resections).
Histology revealed an Askin tumor in the posterior mediastinum, 11 invasive thymomas, 2 thymus epithelial carcinomas, 1 thymus lymphoma, 1 malignant teratoma and 1 liposcarcoma in the anterior mediastinum. 13 patients received postoperative irradiation, 3 chemoradiotherapy, and 1 chemotherapy. 16 (30%) of the 54 anterior mediastinal tumors and 1 (9%) of the 11 posterior mediastinal tumors were malignant, but 14 (43,7%) of the 32 thymomas were malignant. 5-year survival of the malignant thymomas is 33%. In 4 patients, younger than 18 years old, other than invasive thymoma developed, (Askin tumor, liposarcoma, lymphoma, and malignant teratoma) and 3 of them died within a year. Myasthenia gravis appeared in 18,7% of the thymomas, and in one case myasthenia gravis developed after a partial thymectomy.
Malignant mediastinal tumor occurs most commonly in the anterior mediastinum. Almost half of the thymomas were malignant. In childhood, other than malignant thymomas developed, and the prognosis was poor.
The most common location of a malignant mediastinal tumor is the thymus with good prognosis. In young patients the malignant mediastinal tumor located out of the thymus with poor survival. Myasthenia gravis may develop after partial thymectomy.
J. Furak, None.