Anetoderma in cutaneous marginal-zone B-cell lymphoma

Summary Anetoderma is a rare condition, consisting of well‐circumscribed areas of slack skin, in which dermal elastic fibres are destroyed or deficient. We present the case of a 45‐year‐old man with a 25‐year history of deep nodules and plaques gradually progressing to areas of anetoderma. Histological examination found an infiltrate composed of neoplastic cells with lymphoplasmocytoid morphology. The cells were positive for CD20, CD38 and CD138, and there was a monoclonal kappa light chain gene rearrangement of plasma cells. A diagnosis of cutaneous marginal‐zone B‐cell lymphoma was made. The pathogenesis of anetoderma remains unknown, but it is possible that cytokines or other soluble factors produced by the infiltrating lymphocytes have a role in this process.