Merkel Cell Carcinoma in the Setting of Chronic Lymphocytic Leukemia and Diffuse Large B-Cell Lymphoma.

Merkel cell carcinoma (MCC) is a rare, rapidly growing, and highly malignant cutaneous tumor that typically presents in elderly males as an erythematous or violaceous plaque or nodule in sun-exposed areas. Risk factors include long-term ultraviolet (UV) exposure, Merkel cell polyomavirus (MCV) infection, immunosuppression, and lymphoproliferative disorders such as chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Given the aggressive nature of this tumor, patients may present with nodal and distal metastasis.