Merkel cell carcinoma metastatic to the testis

Tumor metastases to the testes are rare and are usually found incidentally at autopsy or after orchiectomy for prostatic carcinoma. It is even more unusual for testicular metastases to be clinically detected or symptomatic. The authors report two cases of clinically detected testicular metastases from Merkel cell carcinoma of the skin. Merkel cell carcinoma metastatic to the testes has not been reported previously. The two tumors, to some degree, resembled testicular lymphomas and the interstitial type of seminoma.