Burkitt Lymphoma: Classification, Pathology and Treatment
Burkitt Lymphoma is a high-grade B-cell non-Hodgkin lymphoma characterized by deregulation and mutation of the C-myc gene on chromosome 8 resulting from a translocation between chromosome 8 and 14.
What is the C-myc gene?
C-myc is a proto-oncogene
Its activation is responsible for tumor proliferation
Overproduction of c-myc protoncogene can change lymphocytes to cancer cells
Burkitt lymphoma has 3 major forms,
- The endemic (African) form
- Non-endemic (sporadic) form.
- Immunodeficiency associated subtype
BL is a childhood tumor but it is observed in adult patients, one of the fastest-growing malignancies with a very high growth fraction.
The male-to-female ratio is 3:1.
Burkitt lymphoma is most common in children
Burkitt lymphoma is a monoclonal proliferation of B lymphocytes characterized by small non-cleaved cells that are uniform in appearance and that produce a diffuse pattern of tissue involvement.
Under the microscope is characterized by the presence of a "starry sky" appearance imparted by scattered macrophages with phagocytes cell debris.
The African form most often involves the maxilla or mandible lesser involvement of abdominal organs.
The sporadic form involves abdominal organs, commonly the distal ileum, cecum, or mesentery and less common involvement of other abdominal organs, pelvic organs, and facial bones.
Burkitt lymphoma carries a translocation of the C-myc oncogene from chromosome 8 to either the immunoglobulin heavy chain region of chromosome 14 ...[T(8;14)] or one of the light chain loci on chromosome 2 kappa light chain [T(8;2)] or chromosome 22 (lambda light chain) [T(8;22)].
The Epstein-Barr virus (EBV) is implicated in the African form and associated with about 20% of sporadic cases.
Rare adult cases are associated with immunodeficiency, particularly AIDS.
The lymphocytes have receptors for EBV and are its specific target.
In the African form, the hosts are unable to mount an appropriate immune response to primary EBV infection, because of coexistent malaria or another infection that is immunosuppressive
Signs and symptoms of Burkitt Lymphoma
The patient is likely to present with the following features;
Soft tissue mass on the jaw or other facial bones,
- Loosening of the teeth
- Weight loss
- Non-tender cervical lymphadenopathy
- Abdominal masses, and ascites.
- Night sweats, epidural mass,
- Skin nodules,
- CNS symptoms, and
- Bone marrow involvement.
- Symptoms of bowel obstruction.
- Derangement of metabolic and renal function
Rare cases can present as acute leukemia with fever, anemia, bleeding, and adenopathy.
Ann Arbor System Staging In Adults
Limited to one group of lymph nodes either above or below the diaphragm, Organ or part of the body other than the lymph nodes, but has not spread to other organs or lymph nodes.
lymphoma in two or more lymph node groups on the same side of the diaphragm only one organ involved and has spread to the lymph nodes near that organ
lymphoma is present in groups of lymph nodes on both sides of the diaphragm. It may involve an organ or site outside the lymph nodes, the spleen, or both.
The lymphoma is disseminated throughout one or more organs outside the lymph nodes. There may or may not be involvement of lymph nodes that are remote from the affected organs.
For each of the stages
A -No general symptoms
B- This is used for patients with any of the following features:
- Unexplained loss of more than 10% of body weight in the last six months
- Unexplained fever
- Drenching night sweats
E - malignancies outside the lymph nodes
D for the skin or H for the liver
ST. Jude's Children's Research Hospital Staging In Children
single tumor or diseased lymph node
two or more tumors or diseased lymph nodes on the same side of the diaphragm
large chest or abdominal tumor
Involvement of the bone marrow and central nervous system
- Full blood count and Erythrocyte sedimentation rate
- serum Electrolytes levels
- Urea, and creatinine
- Uric acid levels
- Liver function tests.
- Biopsy of suspected lymph nodes or other disease sites,
- FNA of the lymph node may also be done.
- CSF also should be evaluated in all cases.
- Cytogenetic studies of peritoneal or pleural fluid
- C-XR rule out lung metastasis
- Chest CT if the chest x-ray is abnormal
- Abdominal ultrasound
- Abdominal CT scan
- Head or spinal CT scan or MRI
- Bone scan and plain bone radiographs
Treatment of Burkitt Lymphoma
- Transfuse if one is pale
- Intravenous fluids if one is dehydrated to correct the dehydration
- Antiemetics if on chemotherapy
- Treat tumor lysis syndrome
- Antipyretics to reduce the fever.
- Chemotherapy- combined
- Alkylating agents, glucocorticoids, urate oxidase enzymes