B u r k i t t L y m p h o m a
General
Note: That's B-cell ALL, as opposed to B cell precursor ALL (very different!).
• There's a somewhat artificial distinction between patients who have just
lymph node involvement (these patients are often said to have Burkitt
lymphoma) and those that have just blood and/or bone marrow involvement
(these patients are often said to have B-cell ALL). This is an unofficial - but
frequently-used - way of describing the disease.
Clinical Features
• Usually affects children, young adults.
• Occurs in endemic and sporadic forms
• Endemic form occurs most commonly in Africa, usually presents as a
rapidly enlarging jaw mass, and is associated with EBV infection.
• Sporadic form can occur anywhere in the world, often presents with an
abdominal mass, and is not associated with EBV infection.
Morphology
• Pattern: Diffuse. Lymph node looks like a starry sky at low power due to all
the macrophages with ingested nuclear debris!
• Cytology: medium-sized cells with prominent nucleoli, scant cytoplasm, very
high mitotic rate.
Immunophenotype
• B-cell.
• NOT TdT positive!
Translocation
• t(8;14)
• The c-myc proto-oncogene (on chromosome 8) moves next to the
immunoglobulin heavy chain gene (on chromosome 14). C-myc gets way
overexpressed since it's sitting right next to the heavy chain gene (which is
constantly being transcribed)
Treatment and Prognosis
• New chemotherapy treatment regimens (with high-dose methotrexate and
cyclophosphamide) are very effective.
• Patients with the sporadic form are usually cured.
• Patients with the endemic form respond well to treatment initially, but often
relapse.
