Stereotactic radiosurgery for intracranial hemangiopericytomas: a multicenter study.
OBJECTIVE Hemangiopericytomas (HPCs) are rare tumors widely recognized for their aggressive clinical behavior, high recurrence rates, and distant and extracranial metastases even after a gross-total resection. The authors report a large multicenter study, through the International Gamma Knife Research Foundation (IGKRF), reviewing management and outcome following stereotactic radiosurgery (SRS) for recurrent or newly discovered HPCs. METHODS Eight centers participating in the IGKRF participated in this study. A total of 90 patients harboring 133 tumors were identified. Patients were included if they had a histologically diagnosed HPC managed with SRS during the period 1988-2014 and had a minimum of 6 months' clinical and radiological follow-up. A de-identified database was created. The patients' median age was 48.5 years (range 13-80 years). Prior treatments included embolization (n = 8), chemotherapy (n = 2), and fractionated radiotherapy (n = 34). The median tumor volume at the time of SRS was 4.9 cm3(range 0.2-42.4 cm3). WHO Grade II (typical) HPCs formed 78.9% of the cohort (n = 71). The median margin and maximum doses delivered were 15 Gy (range 2.8-24 Gy) and 32 Gy (range 8-51 Gy), respectively. The median clinical and radiographic follow-up periods were 59 months (range 6-190 months) and 59 months (range 6-183 months), respectively. Prognostic variables associated with local tumor control and post-SRS survival were evaluated using Cox univariate and multivariate analysis. Actuarial survival after SRS was analyzed using the Kaplan-Meier method. RESULTS Imaging studies performed at last follow-up demonstrated local tumor control in 55% of tumors and 62.2% of patients. New remote intracranial tumors were found in 27.8% of patients, and 24.4% of patients developed extracranial metastases. Adverse radiation effects were noted in 6.7% of patients. During the study period, 32.2% of the patients (n = 29) died. The actuarial overall survival was 91.5%, 82.1%, 73.9%, 56.7%, and 53.7% at 2, 4, 6, 8, and 10 years, respectively, after initial SRS. Local progression-free survival (PFS) was 81.7%, 66.3%, 54.5%, 37.2%, and 25.5% at 2, 4, 6, 8, and 10 years, respectively, after initial SRS. In our cohort, 32 patients underwent 48 repeat SRS procedures for 76 lesions. Review of these 76 treated tumors showed that 17 presented as an in-field recurrence and 59 were defined as an out-of-field recurrence. Margin dose greater than 16 Gy (p = 0.037) and tumor grade (p = 0.006) were shown to influence PFS. The development of extracranial metastases was shown to influence overall survival (p = 0.029) in terms of PFS; repeat (multiple) SRS showed additional benefit. CONCLUSIONS SRS provides a reasonable rate of local tumor control and a low risk of adverse effects. It also leads to neurological stability or improvement in the majority of patients. Long-term close clinical and imaging follow-up is necessary due to the high probability of local recurrence and distant metastases. Repeat SRS is often effective for treating new or recurrent HPCs.
Department of Neurosurgery and Gamma Knife Center, University of Virginia Health System, Charlottesville, Virginia.
Or
O
Cohen-Inbar
Neurological Institute, Taipei Veterans General Hospital, and National Yang-Ming University, Taipei, Taiwan; and.
Cheng-Chia
CC
Lee
Department of Neurosurgery, University of Pittsburgh, Pennsylvania.
Seyed H
SH
Mousavi
Department of Neurosurgery, University of Pittsburgh, Pennsylvania.
Hideyuki
H
Kano
Department of Neurosurgery, University of Sherbrooke, Centre de Recherche Clinique Étienne-LeBel, Sherbrooke, Quebec, Canada.
David
D
Mathieu
Department of Neurosurgery, University of Pittsburgh, Pennsylvania.
Antonio
A
Meola
Department of Neurosurgery, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona.
Peter
P
Nakaji
Department of Neurosurgery, Barrow Neurological Institute and St. Joseph's Hospital and Medical Center, Phoenix, Arizona.
Norissa
N
Honea
Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan.
Matthew
M
Johnson
Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, Ohio.
Mahmoud
M
Abbassy
Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, Ohio.
Alireza M
AM
Mohammadi
Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Cleveland Clinic, Cleveland, Ohio.
Danilo
D
Silva
Neurological Institute, Taipei Veterans General Hospital, and National Yang-Ming University, Taipei, Taiwan; and.
Huai-Che
HC
Yang
Department of Radiation Oncology, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan.
Inga
I
Grills
Department of Neurosurgery, New York University Langone Medical Center, New York, New York.
Douglas
D
Kondziolka
Department of Neurosurgery, New York University Langone Medical Center, New York, New York.
Gene H
GH
Barnett
Department of Neurosurgery, University of Pittsburgh, Pennsylvania.
L Dade
LD
Lunsford
Department of Neurosurgery and Gamma Knife Center, University of Virginia Health System, Charlottesville, Virginia.
Jason
J
Sheehan
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006393:Hemangiopericytoma / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000532:radiotherapy; D011379:Prognosis; D016634:Radiosurgery; D012189:Retrospective Studies; D016019:Survival Analysis; D055815:Young Adult
ARE = adverse radiation effect; EBRT = external beam radiotherapy; GKRS = Gamma Knife radiosurgery; GTR = gross-total resection; Gamma Knife; HPC = hemangiopericytoma; IGKRF = International Gamma Knife Research Foundation; OS = overall survival; PFS = progression-free survival; RTOG = Radiation Therapy Oncology Group; SRS = stereotactic radiosurgery; STR = subtotal resection; hemangiopericytoma; multicenter study; stereotactic radiosurgery