Malignant peripheral nerve sheath tumour of the parapharyngeal space in a patient with neurofibromatosis type 1.

A malignant peripheral nerve sheath tumour, the sarcoma most common in patients with neurofibromatosis type 1, arising in the parapharyngeal space is rare. They usually arise from pre-existing neurofibromas, particularly the plexiform type. The most common presenting symptoms are an enlarging neck mass, pain, and a neurological deficit. They are aggressive tumours that carry a poor prognosis despite wide excision and adjuvant radiochemotherapy. Patients with neurofibromatosis type 1 should be investigated, including deep biopsy, if pain and enlargement of the neurofibromas or any neurological deficit develop.