Intravascular Large B-Cell Lymphoma

Definition

A rare subtype of diffuse large cell lymphoma characterized by the presence of lymphoma cells in the lumina of small vessels

Predominantly Intravascular and Intrasinusoidal Involvement
- Brain and skin most common sites of involvement
- Capillaries to medium sized vessels
- May involve sinusoids of liver, spleen and bone marrow
- Occasional features
  - Endothelial proliferation
  - Thrombosis with recanalization
  - Regional infarction
  - Minor extravascular involvement
- Infiltrate may be free floating or subendothelial
- Atypical cells may appear to be adherent to wall
- Cells may be trapped in clots
Large Noncohesive Cells
- Cytologically malignant nuclei
- Scant to moderate cytoplasm
- Erythrophagocytosis in Asian Variant and Histiocytic Variant
Predominantly B Lineage
- Originally thought to be a neoplasm of endothelial cells, now clearly shown to be a lymphoma
- Leukocyte common antigen (LCA) positive
- Most cases B lineage, occasionally T
  - T cell cases best considered a different disease
- Rare reports of true histiocytic lineage cases
May be associated with hemophagocytic syndrome
Occasionally Associated with Conventional Lymphomas

Yasodha Natkunam MD PhD
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting / last update: 5/6/06, 8/24/11