Background: Metastases of malignant melanoma to the bone marrow are very rare. A few case reports are published in the literature with a known primary site.Herein we report a case of metastatic malignant melanoma in bone marrowwith occult primary.

Case: A 55-year-old-male presented with complains of bone pain. X ray and MRI hip revealed osteoporotic changes with multiple altered hypointensity lesions. Bone marrow aspirate and biopsy suggested metastatic malignant melanoma, which was confirmed by immunohistochemistry. No primary site was identified and it remained occult until patient developed blurring of vision 2 months later the primary diagnosis. That time possibility of choroidal melanoma was given considering the initial diagnosis on bone marrow. Patient died 3 months post diagnosis.

Conclusion: Malignant melanoma is a notorious neoplasma which primarily may present directly as distant metastasis with aggressive behavior and poor prognosis. Clinicians must be aware of the varied clinical manifestations of disseminated malignant melanoma even if the primary site is not evident.

Key words: Melanoma, bone marrow metastasis, occult primary