Amyloid light chain deposition associated with dermatofibroma: serendipity or association?

Primary cutaneous amyloidosis, also known as nodular amyloidosis, is defined as deposition of amyloid light chain in the skin in the absence of a systemic cause of amyloidosis. Such amyloid is produced by a localized aggregate of clonal plasma cells. In contrast, secondary cutaneous amyloidosis is related to lesions such as squamous cell carcinoma, Bowen disease, basal cell carcinoma, and discoid lupus erythematosus, and has been shown in most cases to be derived from keratin epithelial elements. Herein, we present a unique case of nodular amyloidosis occurring in association with a cellular dermatofibroma.