A Case of Merkel Cell Carcinoma duringBiolog ics Treatment of Rheumatoid Arthritis

Abstract

A 77-year-old Japanese female was referred to our hospital with an erythematous nodular lesion on her left cheek. Approximately one month previously she had first noticed a nodule with a diameter of approximately 1.0 cm. She suffered from rheumatoid arthritis, which had been treated with etanercept for 3 years followed by injections of adalimumab duringthe last 2 years. The histological diagnosis was Merkel cell carcinoma. The tumor was excised. The patient underwent subsequent conventional fractionated radiation therapy. On the latest follow-up 3 months later, the patient was doingwell with no recurrence of disease. The immunosuppression associated with long-term use of biologics may have induced the development of Merkel cell carcinoma.