[Spindle cell sarcoma of the female breast].

Malignant mesenchymal breast tumors are extremely rare. Without cystosarcoma phylloides, the frequency of primary sarcomas is 0.6% of all neoplasms of the breast. A case is reported of an adolescent girl, and the diagnostic features and treatment are discussed in correlation to the literature data. The pathogenesis of the sarcoma and the possible connection with Epstein-Barr viral infection is analysed. All treatment modalities with surgery, radiation therapy and systemic cytostatic application were carried out. Nevertheless, the patient developed twice a local recurrence. Then we started a high-dose Beta-Interferon treatment. Until today a total disease-free survival is established.