Spinal intramedullary melanocytoma: systematic review & clinical management considerations

Spinal intramedullary melanocytoma (SIM) is an exceptionally rare benign melanocytic tumor of the central nervous system, with only a limited number of cases reported to date. Diagnosis is frequently delayed and relies on histopathological confirmation to differentiate SIM from other melanocytic lesions, including malignant melanoma. Owing to the rarity of this entity, its natural history, optimal management, and follow-up strategies remain insufficiently defined. We aimed to systematically synthesize the available evidence on clinical presentation, treatment strategies, and outcomes of SIM. A systematic review was conducted according to PRISMA guidelines. PubMed and Cochrane Library were searched up to April 15th, 2026 for reports of histologically confirmed SIM. Case reports and case series in English, French, and Spanish were included. Extracted data comprised demographics, tumor location, clinical presentation, treatment, extent of resection (EOR), adjuvant therapy, and outcomes. Descriptive statistics with 95% confidence intervals were calculated. An institutional illustrative case with 3-year follow-up is presented to complement the literature. Twenty-six publications comprising 35 patients were included. Mean age was 47 years and 40.0% were male. SIM most commonly involved the lower thoracic cord (68.8%). Sensory deficits (74.3%) and motor weakness (68.6%) were the predominant presenting symptoms. At long-term follow-up, neurological status was stable or improved in 84.0% of cases. Overall mortality was 17.1%; only 5.7% of deaths were directly attributable to local tumour progression. Recurrence occurred in 43.3% (13/30) during a mean follow-up of 28.1 months. Across resection groups, recurrence and long-term neurological outcome followed a graded pattern with extent of resection, but the trend test did not reach significance for recurrence (Cochran-Armitage trend test, p = 0.053) and was only of borderline significance for long-term outcome (p = 0.040); given the small, sparse subgroups these findings are hypothesis-generating. Although histologically benign, SIM carries a relevant risk of recurrence and neurological morbidity. Available evidence supports maximal safe resection as the primary treatment goal. Adjuvant radiotherapy may be considered after incomplete resection. Given the potential for delayed recurrence, structured and long-term MRI surveillance appears warranted.