title: Hemangiopericytomas in the Central Nervous System: A Multicenter Study of Korean Cases with Validation of the Usage of STAT6 Immunohistochemistry for Diagnosis of Disease.
abstract: Hemangiopericytoma (HPC) in the central nervous system (CNS) is a rare disease with distinctive biological/clinical characteristics compared with meningioma.
  
  
  
  Cases of HPCs of the CNS were collected, and clinicopathological records were retrospectively reviewed and analyzed. Immunohistochemistry (IHC) for proliferative markers (Ki-67, PHH3) and STAT6 were performed.
  
  
  
  A total of 140 cases were collected, with mean follow-up of 77 months (median 58.8 months; range 0.53-540.5 months). 1-, 5-, 10-, and 20-year survival rates were 99.1, 94.0, 74.4, and 61.9 %, respectively. Thirty-nine patients (27.9 %) had recurrent disease. Mean and median times to recurrence were 62.9 and 47.3 months with 1-, 5-, 10-, and 20-year recurrence-free survival rates of 98.3, 78.3, 50.1, and 11.0 %, respectively. Thirteen patients (9.3 %) developed extracranial metastases. No adjuvant radiation therapy, higher histologic grades, failure of gross-total resection, and cases with gamma-knife surgery (GKS) were factors associated with shorter disease-free survival (log-rank test, p = 0.02, 0.00, 0.02, 0.00), among which high histologic grade and cases with GKS were significant in multivariable analysis. Strong nuclear STAT6 expression was noted in HPCs in 62 cases of HPCs (60/62, 96.8 %), whereas diffuse weak positivity was demonstrated in all meningioma cases.
  
  
  
  The survival rate in patients with HPC 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 transcript with surrogate IHC marker is a valuable diagnostic tool in the differential diagnosis of the disease.
authors.affiliation: College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Korea.
authors.forename: Junjeong
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Pathology, College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Sung-Hye
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Pathology, College of Medicine, Asan Medical Center, University of Ulsan, Seoul, Korea.
authors.forename: Shin Kwang
authors.initials: SK
authors.lastname: Khang
authors.affiliation: Department of Diagnostic Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yeon-Lim
authors.initials: YL
authors.lastname: Suh
authors.affiliation: Department of Pathology, Keimyung University Dongsan Medical Center, Daegu, Korea.
authors.forename: Sang Pyo
authors.initials: SP
authors.lastname: Kim
authors.affiliation: Department of Pathology, Kangnam St. Mary's Hospital, Catholic University, Seoul, Korea.
authors.forename: Youn Soo
authors.initials: YS
authors.lastname: Lee
authors.affiliation: SU Yonsei Eye Clinic, Seoul, Korea.
authors.forename: Hyun Seok
authors.initials: HS
authors.lastname: Kwon
authors.affiliation: Department of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seok-Gu
authors.initials: SG
authors.lastname: Kang
authors.affiliation: Department of Pathology, College of Medicine, Yonsei University, Seoul, Korea. paxco@yuhs.ac.
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D016543:Central Nervous System Neoplasms / Q000175:diagnosis* / Q000378:metabolism* / Q000473:pathology; D002648:Child; D003937:Diagnosis, Differential; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006393:Hemangiopericytoma / Q000175:diagnosis* / Q000378:metabolism* / Q000556:secondary; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008579:Meningioma / Q000175:diagnosis* / Q000378:metabolism; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000378:metabolism*; D056910:Republic of Korea; D012189:Retrospective Studies; D050800:STAT6 Transcription Factor / Q000378:metabolism*; D015996:Survival Rate; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D050800:STAT6 Transcription Factor; C494101:STAT6 protein, human