Synonym: Malignant Lymphoma of Africa.
- Tropical Africa.
- New Guinea.
- South America where malaria is endemic.
- Sex: Males predominantly affected.
- Age: Young children affected more. Over 80% of cases occur between ages of 3 years and 12 years.
- Seen in areas where malaria is endemic suggesting a possible insect vector of an infective agent.
- The Epstein– Barr virus which causes glandular fever.
- Infectious mononucleosis in young adults in western societies is also closely associated with Burkitt lymphoma.
- Genetics- All types of Burkitt lymphomas are characterized by dysregulation of the c-myc gene found at 8q24.
- MicroRNA expression- It was described that short non-coding RNAs named microRNAs (miRNAs) have important functions in lymphoma biology. In malignant B cells, miRNAs participate in pathways fundamental to B cell development, like B cell receptor (BCR) signalling, B cell migration/adhesion, cell-cell interactions in immune niches and the production and class-switching of immunoglobulins.
Presence of dense lymphoblasts interspersed with large, clear histocytes containing debris derived from rapid cell turn over contributing ‘Starry Sky‘ appearance.
Burkitt lymphoma can be divided into three main clinical variants:
1) Endemic variant
2) Sporadic type and
3) Immunodeficiency-associated variants.
- The Endemic variant
- The Sporadic type of Burkitt lymphoma.
- Immunodeficiency-associated Burkitt lymphoma.
For the purpose of deciding how much treatment is necessary Burkitt lymphoma may be divided into 3 groups:
- Group A – Any localized tumor that has been completely removed by surgery
- Group B – Any tumor that has not been removed by surgery and does not involve the nervous system or more than 25% of the bone marrow
- Group C – Any lymphoma with at least 25% bone marrow involvement or with any brain or spinal involvement
The level of an enzyme in the blood called LDH can be elevated in Burkitt lymphoma. Children with an LDH more than twice the normal level have higher risk disease.
- Tumor multifocal grows rapidly, soft and painless.
- In the typical African form, the disease presents primarily as an extra lymphatic tumor arising in bone of jaw in 60% of patients.
- Maxillary lesions may present as oral or orbital tumors.
- Second commonest presentation is an abdominal tumor involving kidneys, ovaries, retroperitoneal nodes or gastrointestinal tract.
- Other sites include thyroid, testicles, skeleton and breast.
- Bone marrow and CSF involvement present in 1/3rd of patients.
For newly diagnosed Burkitt lymphoma or leukemia, treatment is based on the Group of the disease:
- Group A can be treated with a short course of chemotherapy lasting less than two months. Commonly used drugs are cyclophosphamide, vincristine, prednisone, and doxorubicin.
- Group B can be treated with about 4 months of chemotherapy. The same drugs that are used for treatment of Group A are used for Group B, with the addition of high-dose methotrexate and low-dose cytarabine. The immunotherapy drug rituximab (monoclonal antibody that targets a marker called CDS20 on the lymphoma cells) is often included in the treatment and has been shown to improve the outcome for children with a high LDH levels in the blood. Multiple doses of chemotherapy into the spinal fluid are also an important part of the treatment.
- Group C is treated with about 6 months of chemotherapy with the addition of high-dose cytarabine to the treatment plan. Rituximab is always included in the treatment of this group.
- If the correct treatment is selected, the cure rate for all three groups of Burkitts lymphoma is very high.
Treatment of relapsed or refractory Burkitt lymphoma:
For Burkitt lymphoma that does not respond to initial treatment (refractory) or that comes back after treatment (relapse), there is no standard treatment recommendation. Refractory or relapsed Burkitt lymphoma is difficult to treat successfully.
- One common treatment approach for relapsed or refractory Burkitt lymphoma is to give alternative chemotherapy (such as ifosfamide, carboplatin, and etoposide) and immunotherapy (Rituximab) followed by high dose chemotherapy and a stem cell transplant, either from the patient’s own bone marrow (autologous) or sometimes from another person’s bone marrow (allogeneic).
- An immunotherapy drug called Blinotumomab may be effective for treatment of this disease but has not been extensively tested.