Malignant soft tissue tumors of nerve sheath origin.

Thirty-one patients with neurogenic sarcomas treated at Roswell Park Memorial Institute (RPMI) during a 10-year period were studied. The mean follow-up is 35.5 months. A specific nerve of origin could not be identified in 61.3% of patients. The most frequent site was the proximal lower extremity (38.7%). The only presenting symptom was enlarging mass in 67.7%. There was association with Von Recklinghausen's disease in 42% of the cases. Survival was significantly worse in tumors with Von Recklinghausen's disease (25.6%) compared to patients with solitary malignant schwannomas (50.9%). Twelve of 18 patients who had adequate surgical treatment initially remain disease-free, whereas only 2 of 11 patients referred following partial excision or recurrence remain disease-free (P less than 0.02). Eleven of 18 patients with grade I or II tumor are disease-free, whereas 2 of 10 patients with grade III tumor are disease-free (P less than 0.05). Resection of the sciatic nerve with wide excision is accompanied with a good functional result.