Primary Intracranial Malignant Melanoma: A Histological Stranger in the Brain!

Background An uncommon brain tumor known as primary intracranial malignant melanoma (PIMM) is usually identified after metastatic brain melanoma has been ruled out. It often has a poor prognosis, characterised by early relapse and life-limiting effects. Due to its rarity, there are no established standard treatments for this pathological entity. Case Report A 54-year-old man with an intracranial space-occupying lesion on radiological imaging underwent a left frontotemporal craniotomy and subtotal excision of the tumour, and was histopathologically diagnosed with primary CNS malignant melanoma. The patient was advised to receive adjuvant radiation therapy, but did not receive it, leading to a recurrence after two years. The patient then underwent left frontotemporal craniotomy & excision of the lesion, followed by adjuvant radiation therapy consisting of 60 Gy in 30 fractions at 2Gy/fraction over a duration of 6 weeks with adjuvant temozolomide. On follow-up MRI conducted eight months later, recurrent disease was observed, along with dural and bony metastasis, and he received palliative radiotherapy. The patient is currently undergoing immunotherapy, and his disease is in a stable condition. Conclusion Aggressive behavior and a rare, difficult diagnosis are the hallmarks of PIMM. According to recent research, there are few therapeutic choices available if the main tumor is completely removed.