Merkel cell carcinoma in chronic lymphocytic leukemia Successful treatment with PD-L 1 inhibition, avelumab and chlorambucil

We report the case of an 85-year-old chronic lymphocytic leukemia patient with a local metastatic MCVPyV-negative Merkel cell carcinoma at initial diagnosis. Therapy comprised surgical excision and radiotherapy but without lymphadenectomy. Six months after the primary diagnosis, liver metastases were detected. They responded to the PD-L1 inhibitor avelumab for more than 15 months. Thus, we postulate a synergistic effect of combined therapy with chlorambucil and avelumab through a mutual improvement of immune function, from which both diseases benefit.