Hemangiopericytoma in the central nervous system: treatment, pathological features, and long-term follow up in 38 patients.

OBJECT: The authors reviewed the Mayo Clinic experience with the treatment of hemangiopericytoma in the primary central nervous system (CNS).
METHODS: A retrospective study of all patients at the Mayo Clinic revealed 38 who had been treated for hemangiopericytoma in the CNS. Twenty of these patients were diagnosed in the decade between 1990 and 2000; 18 were initially diagnosed and underwent surgery before 1990. In the patients treated since 1990, the 5-year Kaplan-Meier survival rate was 93%. The 5-year disease-free survival rate was 89%. Sixty percent of patients treated with the aid of stereotactic radiosurgery for recurrent disease were alive 4.4 years after their initial treatment. Salvage chemotherapy was not effective. No survival benefit was detected inpatients who had received initial adjuvant external-beam radiation therapy. High-grade tumors recurred 6.7 years earlier than did low-grade lesions (p = 0.004).
CONCLUSIONS: The 5-year survival rate in patients with hemangiopericytoma of the CNS has improved at the authors' institution during the last 10 years. Although the reason for this is not entirely clear, the authors suspect that the improved treatment of patients with cancer, a 0% intraoperative mortality rate, and the use of radiosurgery in the treatment of recurrent disease all likely contribute. High-grade tumors recurred statistically significantly earlier than low-grade lesions. Current chemotherapies are ineffective in the treatment of hemangiopericytoma of the CNS.