Neurosurgery notes/Tumours/Haematolymphoid and histiocytic tumours/Lymphomas/Intravascular large B-cell lymphoma

Intravascular large B-cell lymphoma

View Details
Status
Done
logo
Parent item
Lymphomas

General

  • Distinctive type of aggressive B-cell lymphoma characterized by exclusively intravascular growth.

Definition

  • Essential
    • Biopsy showing a large B-cell lymphoma with morphological and immunohistochemical confinement of neoplastic B cells to the blood vessel lumen without invasion of the surrounding tissue.

Numbers

  • Rare
  • Age Distribution: It usually manifests in adults.
    • Median Age: 70 years.
    • Age Range: 34–90 years.
  • Sex Predilection: There is no sex predilection for this tumour.

Grading

  • This as an aggressive B-cell lymphoma.
  • A specific numerical CNS WHO grade (1–4) is not provided

Localisation

  • Exclusively intravascular growth.
  • CNS involvement occurs in > 75-85% of cases
    • Brain is nearly always involved
      • Cerebral infarction or subacute encephalopathy.
    • Spinal cord involvement is less common.

Histopathology Features

Macroscopic Features

  • Macroscopy reveals infarcts (acute and/or old), necrosis, and/or haemorrhage.
  • Abnormalities may be inconspicuous.

Microscopic Features

  • Large atypical B cells are present confined to the lumina of cerebral blood vessels.
  • The tumour cells may occlude these vessels, but they do not invade the brain parenchyma, although a few cells may exceptionally extravasate.
Tumour confined in vessel lumen
Tumour confined in vessel lumen

Immunophenotype

  • The neoplastic B cells typically show strong expression of CD20.
  • Exceptional CD20-negative cases have been reported that require immunostaining for additional B-cell markers (e.g., CD79a and PAX5).
  • Lack of CD29 and ICAM1 (CD54) expression is thought to underlie the tumour cells’ inability to migrate transvascularly

Pathogenesis

  • The tumour cells' inability to migrate transvascularly is thought to be due to the absence of CD29 and CD54 (ICAM1) expression.
  • Expression levels of the chemokine receptors CXCR5, CCR6, and CCR7 are decreased.
  • MMP2 and MMP9 are not expressed.
  • The tumour cells express molecules that enable their adhesion to the endothelium but lack those involved in extravasation.

Clinical Features

  • Localization/Involvement: The brain is nearly always involved, while spinal cord involvement is less common, occurring in 75–85% of cases.
  • Demographics: It is rare, usually manifesting in adults, with a median patient age of 70 years. There is no sex predilection.
  • Symptoms: Clinical symptoms mimic those of cerebral infarction.
  • It may also present as subacute encephalopathy.
  • The clinical presentation often mimics cerebrovascular diseases with a stroke-like appearance on MRI.

Radiological Features

  • The hallmarks of its intravascular growth lead to clinical symptoms mimicking those of cerebral infarction.
  • The presentation typically mimics cerebrovascular diseases with a stroke-like appearance on MRI.
  • Abnormalities on imaging may be inconspicuous.

Management

  • Staging should determine involvement of other organs because intravascular lymphoma may be widely disseminated.
  • Methotrexate-based chemotherapy may be beneficial in a subset of patients.

Prognosis

  • The prognosis of intravascular large B-cell lymphoma involving the CNS is poor.