Intravascular metastatic melanoma of the vena saphena magna

Melanoma blood vessel metastases are very uncommon. We report the first recorded case of intravascular metastatic melanoma of the vena saphena magna.

A 74-year-old woman presented with a swelling of the upper third of her left thigh and was suspected of superficial thrombophlebitis. Two intravascular black masses were excised in the vena saphena magna. Histopathologic examination showed an endovascular metastatic melanoma positively staining for HMB45 and S-100 proteins. Acral-lentiginous melanoma of her big toe was then found. Subcutaneous lymph node and chest metastases were discovered and treatment with dacarbazine was initiated, followed by treatment with fotemustine. The patient died 21 months after the diagnosis was made.

Only a few cases of blood vessel metastatic melanoma have been reported. We here report the first recorded case, to our knowledge, of intravascular metastatic melanoma of the vena saphena magna. Surgical exploration allowed rapid diagnosis, and histological examination confirmed the intravascular nature of a hematogenous melanoma metastasis. This case clearly illustrates the need for histologic examination of any thrombotic material.