Malignant melanoma of unknown primary origin presenting as cardiac metastasis.

Malignant melanoma has a very high propensity to metastasize to the heart. However, melanoma may sometimes present as a metastatic lesion in the absence of a primary lesion, which are called melanomas of unknown primary origin. We report a case in which a patient presented with a metastatic maligant melanoma in the right atrium with pericardial effusion and without a primary origin.