Cutaneous metastases in a patient with no previous diagnosis of cancer: diagnostic challenge.

On rare occasions, skin lesions are the first local of metastatic manifestation of internal malignancies. In case of no previous diagnosis of these tumors, the approach of suspicious skin lesions becomes a challenge, especially in differentiating cutaneous metastases and adnexal primary neoplasms. Currently, besides epidemiologic, dermoscopic and histopathologic aspects, the evaluation also integrates immunohistochemical exams and cell markers such as p40 and p63, highly specific for skin metastases. This article describes the case of cutaneous metastases as the sole obvious sign of breast cancer in a previously asymptomatic woman. The diagnosis was made by the finding of neoplastic cells in the dermis and immunohistochemistry compatible with ductal carcinoma.