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Burkitt lymphoma is a B-cell lymphoma occurring primarily in children. Endemic (African), sporadic (non-African), and immunodeficiency-related forms exist.
Burkitt lymphoma is endemic in central Africa and constitutes 30% of childhood lymphomas in the US. The form endemic to Africa often manifests as enlargement of the jaw or facial bones. In sporadic (non-African) Burkitt lymphoma, abdominal disease predominates, often arising in the region of the ileocecal valve or the mesentery. Tumor may cause bowel obstruction. The kidneys, ovaries, or breasts may also be involved. In adults, disease may be bulky and generalized, often with massive involvement of liver, spleen, and bone marrow. CNS involvement is often present at diagnosis or with relapsing lymphoma.
Burkitt lymphoma is the most rapidly growing human tumor, and pathology reveals a high mitotic rate, a monoclonal proliferation of B cells, and a “starry-sky” pattern of benign macrophages that have engulfed apoptotic malignant lymphocytes. There is a distinctive genetic translocation involving the C-myc gene on chromosome 8 and the immunoglobulin heavy chain of chromosome 14. The disease is closely associated with Epstein-Barr virus infection in endemic lymphoma; however, it is uncertain whether Epstein-Barr virus plays an etiologic role. Burkitt lymphoma occurs frequently in patients with AIDS and may be an AIDS-defining disease.
Diagnosis
Diagnosis is based on biopsy of lymph node or tissue from another suspected disease site. Rarely, laparotomy may be used for both diagnosis and treatment. Staging includes CT of the chest, abdomen, and pelvis, bone marrow biopsy, CSF cytology, and PET. Staging studies must be expedited because of rapid tumor growth.
Treatment
Treatment must be initiated rapidly because tumors grow rapidly. An intensive alternating regimen of cyclophosphamide, vincristine, doxorubicin, methotrexate, ifosfamide, etoposide, and cytarabine (CODOX-M/IVAC) plus rituximab results in a cure rate of > 90% for children and adults. Other regimens such as rituximab plus etoposide, prednisone, vincristine (Oncovin), and doxorubicin (R-EPOCH) and rituximab plus cyclophosphamide, vincristine, doxorubicin (Adriamycin), and dexamethasone (R-Hyper CVAD) are also commonly used with success. Meningeal prophylaxis is essential. With treatment, tumor lysis syndrome (see Principles of Cancer Therapy: Tumor Lysis Syndrome) is common, and patients must receive IV hydration, allopurinol often with rasburicase, alkalinization, and close attention to electrolytes (particularly K and Ca).
If the patient presents with bowel obstruction secondary to tumor but the tumor is completely resected at initial diagnostic-therapeutic laparotomy, then aggressive therapy is still indicated. Salvage therapy for treatment failures is generally unsuccessful, underscoring the importance of very aggressive initial therapy.
Last full review/revision October 2012 by Carol S. Portlock, MD
Content last modified November 2012
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