ANGIOTROPIC METASTATIC MALIGNANT-MELANOMA

Three years after excision of a primary malignant melanoma from the lo wer back, a mass was noted in the right scapular region of a 51-year-o ld man. Histopathology revealed a malignant spindle-cell neoplasm inva ding the wall of a deep cutaneous blood vessel. Immunohistochemistry c onfirmed the diagnosis of angiotropic metastatic melanoma and ruled ou t primary leiomyosarcoma. Angiotropism is a rare pattern of metastasis of melanoma; the biochemical mechanisms that permit melanoma cells to undergo hematogenous dissemination, and the favorable milieu that the vascular wall offers for melanoma cells, may be responsible for this unusual growth pattern.