Merkelcel-carcinoom bij gebruik van TNF-α-blokkers

Background

Increasing numbers of patients are being treated with TNF-alpha inhibitors. Two patients in our outpatient clinic developed Merkel cell carcinoma during treatment with TNF alpha inhibitors. Since this is a very rare malignancy, this is a remarkable observation.

Case description

A 70-year-old male with rheumatoid arthritis had been treated with etanercept for two years when he discovered a nodule on his elbow that started growing rapidly. It was diagnosed as Merkel cell carcinoma. Despite treatment, the patient died 2 years later.

A 60-year-old female with rheumatoid arthritis had been treated with adalimumab for 7 months when she discovered a rapidly growing lipoma-like lump on her arm diagnosed as Merkel cell carcinoma. She was successfully treated by surgery and radiation therapy.

Conclusion

Merkel cell carcinoma is an aggressive malignancy with a clinically benign aspect. Patients treated with TNF-alpha inhibitors possibly have an increased risk of developing this malignancy.

Conflict of interest: S. Dubois received compensation for attending a conference on molecular pathology from Menarini Diagnostics. The Laboratorium Pathologie uses antibodies from Novocastra, a subsidiary of Menarini Diagnostics. Financial support for this article: none declared.