A rare case report of primary malignant melanocytoma of foramen magnum and literature review.

Background: Primary malignant melanoma is an extremely rare pathology that can occur anywhere in the brain and spinal cord. Patients often present with symptoms like that of brain tumors. This similarity and inability to make a definitive diagnosis from radiological imaging alone make it a challenging diagnosis. Gross total resection is the accepted mainstay of treatment, while histopathological biopsy can confirm the diagnosis.

Case description: A young gentleman who was otherwise healthy presented with neck pain and right-sided weakness. Magnetic resonance imaging revealed an extra-axial mass at the level of the foramen magnum. The patient underwent lateral sub-occipital craniotomy with C1 laminectomy and maximum safe resection of the lesion. Intra-operatively, a firm, moderately vascular black-colored dura-based lesion was found. The frozen section revealed highly pigmented spindle cell neoplasm, and histopathology confirmed that it was malignant melanoma. Postoperative recovery was unremarkable.

Conclusion: Primary malignant melanoma is rare and very challenging to diagnose. It demands an early diagnosis and meticulous surgical management for a favorable prognosis.