International Journal of General Medicine (Dec 2020)
Anaplastic Pleomorphic Xanthoastrocytoma: A Case Report and Literature Review
Abstract
Jing Liu, Yanhua Sun, Xia Liu Department of Pathology, Shenzhen University 1st Affiliated Hospital, Shenzhen Second People’s Hospital, Shenzhen University School of Medicine, Shenzhen 518035, People’s Republic of ChinaCorrespondence: Xia LiuDepartment of Pathology, Shenzhen University 1st Affiliated Hospital, Shenzhen Second People’s Hospital, Shenzhen University School of Medicine, Shenzhen 518035, People’s Republic of ChinaTel/Fax +86 755 88698000Email [email protected]: With an incidence of less than 1% among astrocytomas, pleomorphic xanthoastrocytoma (PXA) is rare. When its mitotic activity exceeds 5 mitoses/10 high-power fields, PXA is defined as anaplastic pleomorphic xanthoastrocytoma (APXA). This report documents the clinical manifestations and histopathological characteristics of APXA to help prevent future misdiagnoses.Case Presentation: A 28-year-old male patient had a sudden limb twitch and visited a local hospital. A head magnetic resonance imaging scan showed large patches of abnormal signal intensity that were approximately 6.0× 3.3 cm in size in the right frontal and parietal lobes, with iso- to slightly hypointense signals on T1-weighted images (T1WI) and mixed hyperintense signals on T2-weighted images (T2WI). Optical microscopic imaging found pleomorphic tumor cells with sheet-like growth, as well as foamy tumor cells, multinucleated giant cells, pleomorphic cells with atypical nuclei, and acidophilic bodies. Some areas were densely packed with obvious atypia and visible mitoses. The patient tested positive for glial fibrillary acidic protein (GFAP), vimentin (Vim), neuronal nuclear antigen (NeuN), P53, oligodendrocyte transcription factor-2 (OLIG-2), and ATRX, while he tested negative for synaptophysin (Syn), CD34, S-100, BRAF V600E, and IDH1 R132H. The Ki-67 labeling index was 15%. Genetic sequencing showed that IDH1 and IDH2 genes were wild-type, but that his BRAF gene harbored the V600E mutation.Conclusion: APXA is a WHO grade III astrocytoma that can be distinguished from WHO grade II PXA according to the level of mitosis. Imaging may help to inform the difficult differentiation between APXA and epithelioid glioblastoma. Nonetheless, a clear diagnosis warrants carrying out a comprehensive analysis, including histomorphological, immunophenotypic, and molecular assessments.Keywords: pleomorphic xanthoastrocytoma, anaplastic, immunohistochemistry, pathology
