gms | German Medical Science

Material and methods: From the departmental archival files of last 7 years, 24 cases of CHBs, wherein the diagnosis was reviewed and confirmed have been included in the study. A detailed histomorphological and immunohistochemical evaluation was studied.

Results: The age range was 15–68yrs (median: 30 yrs) with sex ratio of Male: Female of 1.2:1 (M-13; F-11). Cerebellum was commonest location (n=20). One case each was seen in brain stem, cervical spinal cord, fourth ventricle and frontal lobe of cerebral hemisphere. von Hippel-Lindau (vHL) disease association was noted in 5 cases. 4 cases were recurrent in nature of which 3 were in association with vHL. Histologically, reticular variant was the predominant subtype (n=15), 5 were of cellular variant and 4 were mixed. Nuclear pleomorphism, nuclear cytoplasmic inclusions, cytoplasmic vacuolation were noted in the stromal cells in varying proportions.Immunohistochemical evaluation evaluation was successful in only 11 cases and of which 8 showed stromal cell positivity for alpha-inhibin.CD56 (NCAM), Nestin and synaptophysin positivity was seen in 6, 7 and 4 cases respectively. Nestin positivity was noted in stroma cells only and no reactivity with the endothelial cells seen. S-100 protein and NSE positivity was seen in 8 and 10 cases respectively. Glial fibrillary acidic protein (GFAP) showed two distinct patterns of immunoreactivity - scattered stromal cell positivity (n:5) and pattern of reactive astrogliosis positivity (n:10). CD44 positivity was noted in 5 cases. VEGF and EGFR positivity was seen in 5 cases each. None of the cases showed positivity for epithelial membrane antigen (EMA) and no stromal cells in any of the cases showed positivity for CD34 and CD31 (however the endothelial cells were highlighted).

Conclusions: Cerebellum is the commonest site of occurrence for HBs and uncommonly can occur in the supratentorial compartment and spinal cord. No histological or immunohistochemical correlation with association with vHL was noted. Reticular variant is commonest histological subtype. The present study do raise a possibility of VEGF as a putative mediator of tumoral angiogenesis and tumorigenesis and EGFR suggests as a possible signal transduction initiator.