Youssef Michael, Larson Alexandra, Udhane Vindhya, Schilter Kala F, Nie Qian, Reddi Honey V
Department of Neurology and the Department of Hematology and Oncology at UT Southwestern Medical Center, Dallas, TX 75235, USA.
Belay Diagnostics, Chicago, IL, 60607, USA.
J Liq Biopsy. 2025 Jul 25;9:100318. doi: 10.1016/j.jlb.2025.100318. eCollection 2025 Sep.
Adult brainstem gliomas are rare and present unique diagnostic and therapeutic challenges due to their critical location and limited biopsy feasibility. Molecular profiling of tumor-derived DNA (t-DNA) isolated from cerebrospinal fluid (CSF) is emerging as a minimally invasive alternative for characterizing these tumors and guiding targeted therapy. A 34-year-old woman with brainstem glioma was treated with a standard course of radiation and temozolomide (TMZ) and remained stable for several years. After surveillance imaging revealed disease progression and raised suspicion of IDH-mutant disease on MRI spectroscopy, molecular profiling of CSF was ordered. The Belay Summit test, a novel NGS-based liquid biopsy assay for central nervous system (CNS) tumors, identified variants in and as well as loss of /. Based on these findings, the patient received a short course of radiation and was started on the inhibitor vorasidenib. This case demonstrates the use of t-DNA from CSF for molecular profiling of adult brainstem glioma to identify actionable genomic alterations without surgical risk and allow patients to receive targeted therapy without tissue diagnosis.
成人脑干胶质瘤较为罕见，因其位置关键且活检可行性有限，故而在诊断和治疗上面临独特挑战。从脑脊液（CSF）中分离出的肿瘤源性DNA（t-DNA）进行分子谱分析，正成为一种微创替代方法，用于对这些肿瘤进行特征描述并指导靶向治疗。一名患有脑干胶质瘤的34岁女性接受了标准疗程的放疗和替莫唑胺（TMZ）治疗，并在数年内病情保持稳定。在监测成像显示疾病进展且磁共振波谱成像（MRI）怀疑为异柠檬酸脱氢酶（IDH）突变疾病后，遂对脑脊液进行分子谱分析。Belay Summit检测是一种针对中枢神经系统（CNS）肿瘤的基于新一代测序（NGS）的新型液体活检检测方法，它检测出了 和 的变异以及 / 的缺失。基于这些发现，该患者接受了短疗程放疗，并开始使用 抑制剂伏拉西尼。本病例展示了利用脑脊液中的t-DNA对成人脑干胶质瘤进行分子谱分析，以识别可采取行动的基因组改变，避免手术风险，并使患者无需组织诊断即可接受靶向治疗。
