Intradural Intramedullary Primary Spinal Melanocytoma: A Rare Case Report

Abstract

Spinal melanocytomas are rare pigmented tumors of the central nervous system commonly affecting females in their fifth decades. It has been reported in various locations with intradural intramedullary being the rarest. Patients can present with varied symptomatology from mild backache to frank myelopathy. Here we report a case of 34-year-old man with no medical comorbidities with vague backache associated with numbness of anterior aspect of right thigh for 1 year aggravated by activities and relieved by rest. His neurologic examination revealed normal power and sensation in both lower limbs except for decreased temperature sensation in right L2 dermatome. MRI of dorsolumbar spine revealed a well-defined lesion that was hyperintense in T1- and hypointense in T2-weighted image at D11–12 region with uniform bright enhancement in gadolinium-enhanced T1 image. The patient underwent laminectomy of D11 and D12, and an en bloc excision was done. Diagnosis of primary intradural intramedullary melanocytoma was made from histopathologic examination. Spinal melanocytomas should be considered as a differential diagnosis for intradural space-occupying lesions. MRI remains the investigation of choice for diagnosis, but histopathologic examination is required to confirm and differentiate from other pigmented tumors and malignant melanomas. Total surgical excision of the tumor remains the standard treatment with radiotherapy reserved for cases of incomplete excision and recurrences.