title: Intracytoplasmic immunoglobulin crystals in follicular lymphoma.
abstract: We report a case of follicular lymphoma with crystal inclusions. Swollen lymph nodes taken from the left neck of a 53- year-old Japanese woman were replaced by follicular proliferation of atypical centroblastic and centrocytic cells with intracytoplasmic crystal inclusions. The crystals were confined to lymphoma cells and were not found in histiocytes. Lymphoma cells were positively immunostained with lambda light chain and mu heavy chain, but the crystals were only weakly so. In situ hybridization of light chains disclosed a monoclonal expression of lambda light chain mRNA in lymphoma cells. The crystals had a periodic linear substructure with about 5-nm intervals. The worldwide literature reports 8 cases, including the current case of non-Hodgkin's lymphoma with crystals confined to the neoplastic cells. The cases did not accompany paraproteinemia and crystal-storing histiocytosis and appear to follow a favorable clinical outcome.
authors.affiliation: Department of Pathology, Hirosaki University School of Medicine, Hirosaki, Japan.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Wada
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ebina
authors.forename: Hidekachi
authors.initials: H
authors.lastname: Kurotaki
authors.forename: Soroku
authors.initials: S
authors.lastname: Yagihashi
mesh_terms: D003460:Crystallization; D003593:Cytoplasm / Q000737:chemistry / Q000473:pathology*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007146:Immunoglobulin lambda-Chains / Q000032:analysis / Q000235:genetics / Q000648:ultrastructure; D007148:Immunoglobulin mu-Chains / Q000032:analysis / Q000235:genetics / Q000648:ultrastructure; D017403:In Situ Hybridization; D008198:Lymph Nodes / Q000737:chemistry / Q000473:pathology*; D008224:Lymphoma, Follicular / Q000737:chemistry / Q000235:genetics / Q000473:pathology*; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis; D012334:RNA, Neoplasm / Q000032:analysis
chemical_list: D007146:Immunoglobulin lambda-Chains; D007148:Immunoglobulin mu-Chains; D012333:RNA, Messenger; D012334:RNA, Neoplasm