[Results of treatment of primary exclusively pulmonary metastatic Ewing sarcoma. A retrospective analysis of 41 patients].

41 patients presenting with primary metastatic Ewing's sarcoma or malignant peripheral neuroectodermal tumor (PNET) with initial metastases restricted to the lungs and/or pleural space were analysed with respect to clinical manifestation and treatment results retrospectively. All patients were treated according to the protocols CESS 81 and CESS 86 of the German Society of Pediatric Oncology and Hematology (GPOH). The time since diagnosis ranges from 19 to 137 months, with a median of 72 months. Median relapse-free survival time was 21.8 months. 18 patients were female, 23 were male. The majority of primary tumors exceeded 100 ml of volume. Preferred sites were the pelvis with 16 cases, the limbs with 14 cases and the chest wall with 6 cases. The histological specification of the tumor was Ewing's sarcoma in 22 and PNET in 11 patients, in 8 cases no specific distinction was given. As to local therapy of the primary tumor, 12 patients underwent radiotherapy, 11 surgery, and 18 a combination of both. Patients were allocated to one of these three options on an individual basis. Cytostatic drug treatment was given according to the GPOH-CESS 81 and CESS 86 protocols. As calculated by means of the Kaplan-Meier analysis, relapse-free survival was 30% ten years after diagnosis. Surgery or pulmonary irradiation of 12-20 Gy was applied to lung metastases. 12 of 27 patients are in continuous complete remission following this therapeutic approach.