[Radiation-induced malignant fibrous histocytoma of the oropharynx].

Malignant fibrous histiocytoma is a rare sarcoma. This is the report of a radiation-induced histiocytoma of the right tonsillar region. Because of squamous cell carcinoma of the left tonsil, a 64-year-old woman was treated with primary surgery and postoperative radiotherapy. Six years later, a histiocytoma was diagnosed histologically within the former field of radiation. This second primary tumor was resected radically. Clinical, radiological, and histological findings are presented, and the importance of this very rare malignant tumor, especially when it is radiation-induced, is discussed.