Multifocal spinal recurrence of intramedullary melanocytoma: a rare case report

Intramedullary melanocytoma of the spinal cord is an extremely rare primary melanocytic tumor, with less than 30 cases reported worldwide. Although histologically benign, these lesions may show locally aggressive behavior and a tendency for recurrence. We report an unprecedented case of multifocal intradural extramedullary recurrence following resection of an intramedullary melanocytoma, an occurrence not previously described in the English-language literature.

A 70-year-old woman presented with rapidly progressive weakness and sensory loss in both lower limbs. Four years earlier, she had undergone total resection of a histologically confirmed intramedullary melanocytoma of the conus medullaris. Current MRI revealed multiple intradural extramedullary lesions extending from the midthoracic to sacral levels, the largest at T5 and T11-T12, causing severe spinal cord compression. The lesions were hyperintense on T1-weighted, hypointense on T2-weighted and markedly hyperintense on T1 SPIR images, consistent with leptomeningeal dissemination of a melanocytic tumor. No intracranial lesions were detected. Given the extensive spinal involvement, further invasive diagnostics or radiotherapy were not indicated, and palliative management with corticosteroids and rehabilitation was initiated. The patient experienced gradual neurological deterioration with early spasticity and minimal partial recovery.

This case demonstrates that even histologically benign spinal melanocytomas can behave destructively and disseminate along the leptomeninges. Awareness of this potential, combined with long-term whole-neuraxis MRI surveillance, is crucial for early detection and timely management. The report highlights the unpredictable clinical course of these rare tumors and the need for individualized multidisciplinary care.