Clinical characteristics and pathogenesis of cerebellar glioblastoma

Abstract

Abstract. Cerebellar glioblastomas (GBMs) are rare, with neither their pathogenesis nor prognosis being completely understood. The present study aimed to clarify the clinical characteristics of cerebellar GBMs by comparison with supratentorial GBMs, focusing particularly on the pathogenesis. The clinical factors between cerebellar (n=10) and supratentorial (n=216) GBMs were compared. Additionally, p53 and epidermal growth factor receptor (EGFR) levels were investigated in six patients by immunostaining as well as the isocitrate dehydrogenase 1 (IDH1) status of five patients by direct sequencing. Eight males and two females participated in the present study, the mean age at diagnosis was 56.6 years and the range 37-75 years. Four patients presented with hydrocephalus and one with brainstem involvement, and two patients were diagnosed with neurofibromatosis type 1. Two patients had previously received radiotherapy, eight patients received postoperative radiotherapy and seven chemotherapy. The mean Karnofsky performance status (KPS) score was lower in patients with cerebellar GBMs compared to those with supratentorial GBM; however, the survival times did not differ between the two groups. All of the cases of six cerebellar GBMs were p53-positive and EGFR-negative, as detected by immunostaining, consistent with secondary GBM. However, no IDH1 mutations were detected in any of the five cases of cerebellar GBMs analyzed, indicating that these tumors were not of the secondary type. The KPS score with cerebellar GBMs may be lower due to hydrocephalus, which was ameliorated by surgery but may have impacted the survival rate. It was confirmed that cerebellar GBMs were identical to supratentorial GBMs with respect to its clinical features, with the possible exception of the KPS score. The present study's genetic analyses indicated that cerebellar GBMs may develop via a pathway different from that of either primary or secondary GBM.

Cerebellar high‐grade astrocytoma with IDH mutations in the elderly: A report of two cases

“…[1][2][3][4]12 Because of its rarity, the nature of the cerebel- no tumors with an IDH1/2 mutation. [1][2][3][4]12 Because of its rarity, the nature of the cerebel- no tumors with an IDH1/2 mutation.…”

“…5 IDH mutations are often detected in grade II or III diffuse glioma and secondary glioblastoma. 1,4,[6][7][8] In addition, there are only a few reports of IDH-mutated diffuse gliomas of infratentorial origin. [14][15][16] In cerebellar high-grade gliomas, IDH mutations are rarely reported.…”

“…[1][2][3][4] Cerebellar highgrade gliomas are likely to affect younger patients compared with those of supratentorial origin 1,3 ; however, the clinicopathological and molecular genetic features of these tumors are poorly understood because of their rarity. [1][2][3][4] Cerebellar highgrade gliomas are likely to affect younger patients compared with those of supratentorial origin 1,3 ; however, the clinicopathological and molecular genetic features of these tumors are poorly understood because of their rarity.…”

“…[1][2][3][4] Cerebellar highgrade gliomas are likely to affect younger patients compared with those of supratentorial origin 1,3 ; however, the clinicopathological and molecular genetic features of these tumors are poorly understood because of their rarity. 1,4,[6][7][8] Here, we present two unusual cases in elderly patients with a mutation in IDH1 or IDH2. 5 Some recent reports investigated IDH1/2 in cerebellar highgrade gliomas immunohistochemically or genetically and revealed that IDH1/2 mutations were extremely rare.…”

“…High-grade gliomas usually occur in the cerebral hemispheres and are rare in the cerebellum. [1][2][3][4] Cerebellar highgrade gliomas are likely to affect younger patients compared with those of supratentorial origin 1,3 ; however, the clinicopathological and molecular genetic features of these tumors are poorly understood because of their rarity. Examination of isocitrate dehydrogenase (IDH) in diffuse glioma is essential for accurate diagnosis based on the updated 2016 World Health Organization (WHO) classification of brain tumors.…”