摘要
Abstract
Purpose To explore the clinical and pathological characteristics,diagnostic features,differential diag-nosis,and prognosis of polymorphous low-grade neuroepithelial tumor of the young(PLNTY).Methods Clinical and imaging data from 7 patients with PLNTY were collected.Morphological evaluation was performed using HE staining.Immunohistochemistry with the EnVision method was used to detect the expression of including CD34,BRAF,IDH1,GFAP,Ki67,and other proteins.BRAF gene mutations were detected by real-time PCR,CDKN2A/B and 1p/19q co-deletion were assessed by FISH,and next-generation sequencing(NGS)was performed on selected cases.Results Among the seven patients,six were male and one was female,aged 8-29 years(median age:22 years).Tumors were located in the temporal lobe(5 cases),left insula and anterior temporal lobe(1 case),and frontotemporal lobe(1 case).Six patients had a history of epilepsy.Histologically,all tumors displayed oligodendroglioma-like areas.Two cases exhibited perivascular pseudorosette-like arrangements,and two showed focal cellular pleomorphism.Calcifica-tion and capillary networks were observed in all cases.Immunohistochemically,all tumors were positive for GFAP and Olig-2 and negative for IDH1(R132H).CD34 showed diffuse positivity in all cases.BRAF was positive in five cases.The Ki67 proliferation index ranged from 1%to 5%.Molecularly,all cases were IDH-wild type,with no 1p/19q co-deletion or CDKN2A/B deletion.BRAF V600E mutants were identified in five cases,and FGFR alterations in two.During follow-up(5-48 months),all patients survived;five remained recurrence-free,while two experienced recur-rence.Conclusion As a rare low-grade neuroepithelial tumor,clinicians and pathologists should master the diagnostic key points and differential diagnosis of PLNTY to avoid misdiagnosis and missed diagnosis.关键词
多形性低级别神经上皮肿瘤/青少年/少突胶质细胞瘤/癫痫/CD34/FGFR/BRAFKey words
polymorphous low-grade neuroepithelial tumors/the young/oligodendroglioma/epilepsy/CD34/FGFR/BRAF分类
医药卫生