MYB-QKI rearrangement in angiocentric glioma

Abstract

Aims: To evaluate the occurrence and diagnostic value of MYB-QKI rearrangement status in angiocentric glioma (AG) in Chinese patients.

Materials and methods: 27 cases were collected from six hospitals, followed by a retrospective analysis of clinical, radiological, and morphological data. MYB protein expression was assessed by immunohistochemical staining (IHC), and the MYB-QKI rearrangement was detected by fluorescence in situ hybridization (FISH).

Results: Among the 27 cases (16 males), the median age at surgery was 17 years (range 3 - 43 years); 24 (88.9%) cases had a history of refractory epilepsy, and the mean history of pre-surgical epilepsy was 13 years (range 1.5 - 27 years); 26 (96.3%) cases had lesions located in the superficial cerebrocortical regions, and 1 (3.7%) case had a lesion in the brainstem. Except for the classic histological features, the involvement of superficial cortex extending to the leptomeninges, microcalcification, and cystic pattern with microcystic formations was observed in 11 (40.7%), 3 (11.1%), and 4 (14.8%) cases, respectively. IHC showed that all 27 cases were positive for glial fibrillary acidic protein (GFAP) and vimentin, and negative for neuronal nuclear antigen (NeuN). The positive rates of epithelial membrane antigen (EMA) and D2-40 were 81.5% (22/27) and 74.1% (20/27), respectively. A total of 14 (51.9%) cases were positive for MYB. The rate of Ki-67 proliferation was 1 - 5% in 25 cases, and in 2 cases with anaplastic features it was 10 and 20%. MYB-QKI rearrangement was revealed by FISH examination in 95.8% (23/24) of the AGs, including 3 cases with atypical histological appearance.

Conclusion: Compared to IHC, FISH was more appropriate for detecting MYB-QKI rearrangement. MYB-QKI rearrangement was detected in the majority of Chinese AG cases, and therefore represents a potential diagnostic biomarker for AG.