A case of fibrosarcoma arising in a recurrent nasopharyngeal angiofibroma 18 years after radiation therapy is described. A review of the medical literature revealed two other documented cases of sarcomatous transformation of angiofibroma, and in both, the angiofibromas had also been irradiated before the sarcomatous transformation. These occurrences should caution against the indiscriminate application of radiation therapy in nasopharyngeal angiofibromas.