Magnetic Resonance Imaging Findings of Brain Tumour with Histopathological Association According to WHO 2021 Classification

Abstract

Introduction: Magnetic Resonance Imaging (MRI) is the gold standard for evaluating brain tumours. However, correlation between MRI findings and histopathological diagnosis, particularly under the WHO CNS 5th edition classification, requires further assessment.
Materials and Methods: This prospective observational study was conducted from April 2024 to September 2025 in the Department of Radiodiagnosis, SRMSIMS, Bareilly. Fifty patients with clinically or radiologically suspected brain tumours underwent MRI followed by histopathological examination after surgery. MRI protocol included T1, T2, FLAIR, DWI/ADC, perfusion imaging, and MR spectroscopy. Histopathological diagnosis was categorized according to the WHO CNS 5th edition classification. Statistical analysis was performed using the chi-square test with p<0.05 considered significant.
Results: The mean age of patients was 38.5 ± 17.6 years with slight female predominance. Headache with vomiting was the most common presenting complaint. Most tumours were supratentorial and larger than 5 cm. MRI commonly showed T1 hypo-/isointensity, T2/FLAIR hyperintensity, diffusion restriction, haemorrhage, ventricular effacement, and midline shift. Meningioma was the most common tumour on both MRI and histopathology. MRI demonstrated an overall diagnostic accuracy of 94% with strong concordance with histopathology (p<0.001), especially for supratentorial tumours. Minor overlap was observed between pilocytic astrocytoma and hemangioblastoma in infratentorial lesions.
Conclusion: MRI shows high diagnostic accuracy and strong concordance with histopathology in brain tumour evaluation. However, molecular biomarkers remain essential for comprehensive WHO 2021 classification and optimal management.