Pa-005. Hemangiopericytomas In Central Nervous System: A Multicenter Study Of Korean Cases

INTRODUCTION: Hemangiopericytoma (HPC) in central nervous system(CNS) is a rare disease which usually shows distinctive biological/clinical characteristics compared with commonly occurred meningioma. The purpose of this study is to investigate the incidence and clinicopathologic characteristics of this particular disease in Korea to highlight the clinical outcome and to provide a practical guideline of pathological diagnosis. METHOD: Cases of hemangiopericytoma of the CNS were collected and clinical and histopathological records were retrospectively reviewed. RESULTS: A total of 141 cases from 141 patients were collected, with median duration of follow up of 58.8months with range of 0.53 to 540.5 months. One year-, 5-year and 10-year survival rates were 98%, 72% and 45% respectively, after the date of diagnosis. There were 39 patients (28%) of recurrent disease. Mean and median time to recurrence were 59.6 and 47 months with 1 year, 5 year and 10-year recurrence free survival rates of 98%, 72% and 45%. Thirteen patients (9%) developed extracranial metastases. Adjuvant radiation therapy, histologic grades, feasibility of gross-total resection and tumor size (>= 6cm) were associated with disease free survival (stratified log rank test, p value= 0.0023, 0.0022, 0.0140 and 0.0469). CONCLUSION: The survival rate in patients with hemangiopericytoma of the CNS is comparable to that of previously reported series. Recurrence remains a critical clinical issue of the disease. Identification of NAB2-STAT6 fusion with surrogate IHC marker is a valuable diagnostic tool in the differential diagnosis of the disease.