Intravascular Large B Cell Lymphoma

 

Epidemiology and Etiology:

    • Adults
    • Hypothesized to result from a defect in homing receptors on neoplastic cells

 

Common sites:

    • CNS
    • Skin
    • Lung
    • kidneys
    • adrenals
    • bone marrow

 

Gross features:

    • widely disseminated in extranodal sites at presentation usually
    • skin lesions most commonly
      • plaques and nodules
    • seen in a wide range of tissues:
      • hemorrhage
      • thrombosis
      • necrosis
    • tumour deposits may not be visible grossly

 

Histologic features:

    • neoplastic lymphoid cells mainly lodged in lumina of small vessels in many organs
      • large lymphocytes
      • vesicular nuclei
      • prominent nucleoli
      • frequent mitoses
    • fibrin thrombi maybe
    • malignant cells rarely seen in peripheral blood or CSF

 

Immunophenotype:

Marker:

Sensitivity:

Specificity:

CD19, CD20, CD22, CD79a

 Most (rarely T cell phenotype)

 

CD5

Some

 

Factor VIII

 

 

 

Molecular features:

    • recent study showing lack of CD29 (beta1 integrin) and CD54 (ICAM-1)
    • immunoglobulin gene rearrangements

 

Other features:

    • extremely aggressive usually
      • poor response to chemo
    • symptoms caused by occlusion of small vessels
      • neurological symptoms
      • skin plaques and nodules
      • nephritic syndrome
      • pyrexia
      • hypertension
      • breathlessness
    • hematologic abnormalities
      • autoimmune hemolytic anemia
      • leucopenia
      • pancytopenia
      • DIC

 

References:

    • WHO blue book (2001)