Choriocarcinoma metastatic to the skin: A rare occurrence associated with dismal outcome

Germ cell tumors (GCTs) are a histologically heterogeneous group of tumors that arise from the primitive germ cell of the embryonic gonad. Choriocarcinoma is a variant of GCTs that is prone to hematogenous metastasis to the liver, lung, and brain. Cutaneous metastasis in choriocarcinoma is rarely encountered with only a few cases reported in literature. We report the case of a 28-year-old male presenting with lower back pain that, upon further work-up, was diagnosed with pure choriocarcinoma of the testes. Around 9 months after his initial presentation, he developed a cutaneous back lesion. Microscopic examination confirmed the presence of choriocarcinoma composed of mononuclear cytotrophoblasts which interweave with multinucleated syncytiotrophoblasts. The patient passed away 3 weeks after the onset of cutaneous metastasis.