Metastatic Merkel cell carcinoma with an unknown primary tumour presenting as lichenoid dermatitis.

Metastatic Merkel cell carcinoma uncommonly presents with an unidentified primary tumour. We report a patient who first presented with lichenoid dermatitis and was found to have Merkel cell carcinoma involving lymph nodes with an unknown primary site. With the rising incidence of Merkel cell carcinoma, it is important to recognize unusual manifestations of this disease as they may become more common in the future.