Multiple eruptive dermatofibromas occurring in association with monoclonal gammopathy of undetermined significance: A case report

Multiple eruptive dermatofibroma is a rare variant of dermatofibroma and often occurs in association with systemic disease, particularly involving immune dysregulation. We present what may be the first reported case of multiple eruptive dermatofibroma in association with monoclonal gammopathy of undetermined significance, a premalignant plasma cell dyscrasia. A 66-year-old male with stable IgM monoclonal gammopathy of undetermined significance developed over 50 asymptomatic papulonodular lesions over two years. Histopathology confirmed dermatofibromas, the timeline of lesion development was consistent with multiple eruptive dermatofibroma, and laboratory evaluation revealed elevated IgM and a monoclonal paraprotein band. This case highlights a novel systemic association between multiple eruptive dermatofibroma and monoclonal gammopathy of undetermined significance. Given the frequent co-occurrence of immune dysregulation in patients with multiple eruptive dermatofibroma, evaluation for underlying systemic immunologic conditions in affected individuals is warranted. Recognition of such associations may facilitate earlier diagnosis and surveillance of systemic disease.