Merkel Cell Carcinoma: A Case Report and Review of Literature

Merkel cell carcinoma (MCC) is a highly aggressive tumor (WHO, 2018), primarily affecting elderly individuals with a history of chronic sun exposure. Researchers link factors such as ultraviolet radiation, immunosuppression, and infection with the Merkel cell polyomavirus (MCPyV) to its etiology. Despite ongoing debate over its cell origin, MCC's immunohistochemical profile and morphological characteristics resemble those of native Merkel cells found in the skin. We present a case observed in the pathology department at the Mohamed VI University Hospital Center in Marrakech. This case study involves a 79-year-old patient without any specific medical history who presented with a rapidly enlarging mass on the upper lip. Merkel cell carcinoma is a highly aggressive skin tumor associated with various causative factors, including UV radiation, immunosuppression, and MCPyV infection. Its diagnosis relies on careful histopathological examination and immunohistochemical profiling. Differential diagnosis considerations are crucial to ensure accurate classification and appropriate management of this challenging malignancy.