Extrafacial Merkel Cell Carcinoma Presenting as a Cyst

Abstract

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin tumor that presents as an erythematous or violaceous nodule in elderly white males with an extensive history of sun exposure. Herein, we report two cases of extrafacial MCC. On exam, lesions presented as a cystic nodule and a firm plaque. We summarize tools from literature review that may aid in earlier diagnosis of MCC as well as implications of primary tumor location in prognosis. In addition, we provide an algorithm for diagnostic workup. MCC is an aggressive malignancy with a poor prognosis and a high risk of local recurrence and nodal metastasis. It is imperative to include MCC in differential diagnosis of cyst/nodule in order to facilitate early detection. J Drugs Dermatol. 2022;21(3):304-308. doi:10.36849/JDD.6248.