Late‐onset skin involvement on the forehead in multicentric Castleman disease

Abstract

A 38-year-old Japanese woman was referred to dermatologists for skin lesions on the forehead. At the age of 28, she developed generalized lymphadenopathy, splenomegaly, anemia, and hypergammaglobulinemia; a few years later, endocrinopathies such as menstruation disorder and galactopoiesis occurred. Histopathological examination of a lymph node revealed the atrophic lymphoid follicles and the interfollicular expansion by the prominent infiltration of mature-appearing plasma cells. Immunohistochemical stains for Igj and k light chains confirmed the polyclonal nature of the plasma cells with an Igj to k ratio of 6:4. These results led hematologists to diagnose plasma cell type multicentric Castleman disease (MCD), and she had been treated with systemic corticosteroids and rituximab with little improvement. At the initial dermatological consultation, clinical examination revealed a 3-year history of reddish-brown, nonpruritic, slightly depressed macules on the forehead which had occurred 7 years after the diagnosis of MCD (Fig. 1a). Laboratory investigations revealed anemia (Hb: