Immunoglobulin G4-Related Disease, Lymphadenopathy, and Lymphoma: Histopathologic Features and Diagnostic Approach

Abstract

Lymphadenopathy occurring in patients with immunoglobulin G4 (IgG4)-related disease, termed IgG4-related lymphadenopathy, shows morphologic heterogeneity and overlap with other nonspecific causes of lymphadenopathy including infections, immune-related disorders, and neoplasms. This review describes the characteristic histopathologic features and diagnostic approach to IgG4-related disease and IgG4-related lymphadenopathy, with comparison to nonspecific causes of increased IgG4-positive plasma cells in lymph nodes, and with emphasis on distinction from IgG4-expressing lymphoproliferative disorders.

Keywords: IgG4; IgG4-related disease; IgG4-related lymphadenopathy; Lymphadenopathy; Lymphoma.