Abstract

EGFRVIII-POSITIVE IDH-WILDTYPE LEFT FRONTAL GLIOBLASTOMA: AN ILLUSTRATION OF BIOMARKER-GUIDED THERAPY AND CLINICAL TRIAL INVOLVEMENT

Deepak Kumar Punna*, Annapurna Kothagadi, Sai Keerthana Mandli, Amatul Noor Ayesha

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Abstract

Glioblastoma (GBM), a WHO Grade 4 astrocytic tumour, remains the most aggressive primary malignant brain tumour in adults, with limited survival despite multimodal therapy. Molecular profiling has become essential for guiding prognosis, individualized treatment, and clinical trial eligibility. This case report illustrates the role of biomarker-driven management in a 70-year-old male diagnosed with left frontal glioblastoma, characterized by IDH-wildtype, MGMT-unmethylated, and EGFRvIII-positive status. The patient presented with subacute headache, mild expressive aphasia, behavioural changes, and right-arm weakness. MRI revealed a 4.2 × 3.8 cm ringenhancing lesion with necrosis and vasogenic edema. Stereotactic biopsy confirmed glioblastoma with pseudo palisading necrosis and a Ki-67 index of 35%. Given the molecular profile, the patient underwent maximal safe resection followed by standard chemoradiation (Stupp protocol). He was enrolled in an EGFRvIII-targeted peptide vaccine clinical trial, aimed at inducing a selective cytotoxic immune response against tumour-specific neoantigens. Over 10 months of followup, the patient demonstrated stable neurological function and partial radiological response (40% reduction in enhancing lesion volume). This case underscores the importance of integrating molecular diagnostics, precision immunotherapy, and multidisciplinary management in glioblastoma, particularly for EGFRvIII- positive tumours where targeted approaches may enhance clinical outcomes.

Keywords: Glioblastoma multiforme (GBM); EGFRvIII mutation; IDH- wildtype; MGMT promoter unmethylated; Precision oncology; Biomarker- guided therapy; Targeted immunotherapy; Peptide vaccine; Clinical trial participation; Molecular profiling; Neuro-oncology; High-gr