A 45-year-old man presents with progressive headache, nausea, and bilateral papilledema. MRI brain shows a heterogeneously enhancing mass in the corpus callosum with involvement of both hemispheres producing a 'butterfly pattern.' What is the most likely diagnosis?
- A Meningioma
- B Glioblastoma multiforme (GBM) ✓
- C Brain metastasis
- D Primary CNS lymphoma
Correct answer: B. Glioblastoma multiforme (GBM)
Explanation
The 'butterfly glioma' pattern — a heterogeneously enhancing mass crossing the corpus callosum to involve both hemispheres in a butterfly configuration — is pathognomonic of glioblastoma multiforme (GBM), the most malignant primary brain tumor (WHO Grade IV). GBM has a median survival of 14-16 months even with maximum safe resection followed by Stupp protocol (temozolomide + concurrent and adjuvant radiotherapy). The corpus callosum crossing pattern reflects the tumor's spread along white matter tracts and rules out meningioma (extra-axial) and most metastases.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.