Table of Contents
Definition / general | Treatment | Gross description | Microscopic (histologic) description | Positive stains | Negative stains | Differential diagnosisCite this page: Mansouri J. Diffuse large B cell lymphoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/spleendiffuselargeBcell.html. Accessed May 29th, 2020.
Definition / general
- Most frequent splenic lymphoma (50%), usually due to secondary dissemination from other sites
- Splenomegaly, left upper quadrant pain, fever, weight loss, elevated erythrocyte sedimentation rate; also hypersplenism
- May be associated with HIV
- Commonly metastasizes to hilar and retroperitoneal lymph nodes
- May coexist with SLL / CLL
Treatment
- Splenectomy, chemotherapy
Gross description
- Large or small nodules or diffuse red pulp infiltration, may invade splenic capsule and adjacent structures
Microscopic (histologic) description
- Sheets of pleomorphic large cells (centroblasts, immunoblasts, anaplastic) with frequent mitotic figures, often plasmacytoid features; T cell / histiocyte rich tumors mimic reactive lesions
- Patterns: macronodular (60%, usually stage I, usually favorable outcome, BCL6+), micronodular (30%, advanced clinical stage and often death due to disease, BCL6+, includes T cell rich B cell subtype), diffuse red pulp infiltration (10%, advanced clinical stage and often death due to disease, BCL6+) (Am J Surg Pathol 2003;27:895)
- Macronodular:
- Homogenous compact masses of large lymphocytes effacing splenic architecture, usually necrosis, often sclerosis
- Tumor cells usually centroblasts, also immunoblasts and polylobated cells
- Often macrophages, occasional epithelioid histiocytes
- Micronodular:
- Includes T cell / histiocyte rich B cell lymphoma (Am J Surg Pathol 2003;27:903)
- Uniform miliary pattern with focal coalescence of splenic white pulp micronodules
- Variable infiltration of red pulp
- Nodules composed of large B cells with occasional small T cells and CD68+ histiocytes
- No residual mantle zone, no follicular dendritic cell network
- Small areas of necrosis and macrophages occasionally seen
- May mimic reactive conditions
- Diffuse red pulp infiltration:
- Diffuse tumor infiltration of red pulp cords and sinusoids with scattered residual white pulp islands
- No pseudosinuses
- Tumor cells are centroblastic, polylobated or pleomorphic
- Usually no necrosis
- Macronodular:
Negative stains
- CD10 (usually), CD138, EBV, keratin (rarely positive, Am J Surg Pathol 1996;20:346)
Differential diagnosis
- Follicular lymphoma: nodular but different cytology, most cells are CD20+, CD10+
- Granuloma
- Hodgkin lymphoma: CD15+, CD30+, prominent eosinophils, negative for B cell markers and BCL6
- T cell lymphoma: T cells usually involve red pulp, are atypical, don't form nodules
