Unusual presentation of melanoma of unknown primary origin: A case report and review of literature

Abstract

Malignant melanomas often present with metastasis to regional lymph nodes. Patients are also known to present with metastatic nodes in the absence of a known primary. However metastatic melanoma involving the stomach is rare in the scenario of an unknown primary lesion. We present a case of a 41-year-old lady who was treated for nodal disease in the right axilla 8. months earlier with an unknown primary. She later presented to us with a recurrent right axillary swelling and on evaluation was found to also have a nodular deposit on the greater curvature of the stomach. Histopathology of the deposit in conjunction with immunohistochemical markers S.100P, Melan-A and HMB-45, confirmed the diagnosis of malignant melanoma. The patient underwent surgical excision of both lesions and is now on regular follow-up.