Cutaneous metastasis of testicular choriocarcinoma, diagnosed by fine-needle aspiration cytology: a rare case report and review of the literature.

Skin metastasis of testicular choriocarcinoma is very rare. Until now about nine cases have been reported in the English literature; however, only one of them has been diagnosed by fine-needle aspiration (FNA) cytology. Herein, we report our experience with FNA cytology diagnosis of a metastatic testicular choriocarcinoma to the skin of chin. The combination of highly atypical mononuclear cells (cytotrophoblasts) and multinucleated malignant cells (syncytiotrophoblasts) are characteristic of metastatic tumor in a known case of choriocarcinoma of testis.