The patient underwent surgery for tumor resection with intraoperative neuro-electrophysiological functional monitoring due to the location of the tumor. Subtotal resection was achieved. More extensive resection was limited by declining motor evoked potential monitoring.
Following the surgery, the prior biopsy pathology was amended. An orthogonal assay for IDH mutation was performed on a new instrument at this institution and found the previously reported R132S variant to be below the threshold of diagnostic confidence. The amended pathology report is as follows:
Final pathologic diagnosis:
Integrated diagnosis: glioblastoma, IDH-wildtype, CNS WHO grade 4
Histologic diagnosis: astrocytoma with mitotic activity, necrosis, and microvascular proliferation
CNS WHO grade: 4
Molecular findings:
- IDH1/2: WILD TYPE (PCR, amended)
- ATRX: RETAINED nuclear staining (immunohistochemistry; consistent with
wild type) - p53: scattered weakly positive cells (immunohistochemistry; consistent
with wild type) - MGMT promoter methylation: NEGATIVE (PCR)
- 1p/19q: NOT co-deleted (FISH)