title: Unclassifiable B-cell lymphoma occurring after necrotizing pneumonia.
abstract: We report a case of CD20+ grey zone lymphoma (GZL) with Reed Sternberg cells as an unexpected pathological diagnosis of a destroyed right lower lobe after necrotizing pneumonia. These GZLs show overlapping features of classical Hodgkin's lymphoma and diffuse large B-cell lymphoma. GZLs are a rare specific entity of lymphomas, and the aetiology is unknown. The diagnosis is confirmed by pathological, immunohistochemical and molecular analyses. The optimal treatment is unknown. The prognosis of these patients is poor.
authors.affiliation: Department of Thoracic and Vascular Surgery,  Antwerp University Hospital, Edegem (Antwerp),  Belgium.
authors.forename: Anouschka
authors.initials: A
authors.lastname: Cogen
authors.forename: Greet
authors.initials: G
authors.lastname: Bries
authors.forename: Sofie
authors.initials: S
authors.lastname: Verbeke
authors.forename: Paul
authors.initials: P
authors.lastname: Van Schil
mesh_terms: D018951:Antigens, CD20 / Q000096:biosynthesis; D000970:Antineoplastic Agents / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols; D006689:Hodgkin Disease / Q000145:classification / Q000473:pathology; D006801:Humans; D016393:Lymphoma, B-Cell / Q000145:classification / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009336:Necrosis; D011013:Pneumonectomy; D018410:Pneumonia, Bacterial / Q000473:pathology*; D049268:Positron-Emission Tomography; D016539:Reed-Sternberg Cells / Q000473:pathology; D014057:Tomography, X-Ray Computed
chemical_list: D018951:Antigens, CD20; D000970:Antineoplastic Agents