Burkitt's leukemia

Burkitt's leukemia is a rare type of leukemia closely related to Burkitt's lymphoma, a form of non-Hodgkin's lymphoma. It is characterized by the rapid growth of abnormal B lymphocytes, a type of white blood cell that plays a role in the immune system. The disease is named after Denis Parsons Burkitt, a surgeon who first described the lymphoma in African children in 1958. Burkitt's leukemia/lymphoma can be divided into three main types: endemic, sporadic, and immunodeficiency-related.

Etiology and Pathogenesis

Burkitt's leukemia is caused by a chromosomal translocation between chromosomes 8 and 14, which results in the overexpression of the c-MYC oncogene. This genetic alteration is a hallmark of the disease and plays a crucial role in the pathogenesis of Burkitt's leukemia by promoting the rapid division of B cells. Epstein-Barr virus (EBV) infection is strongly associated with the endemic form of the disease, particularly in Africa, suggesting a role in its development. However, the sporadic and immunodeficiency-related forms of Burkitt's leukemia/lymphoma are less consistently associated with EBV.

Clinical Features

Patients with Burkitt's leukemia often present with rapidly growing tumors, abdominal pain, intestinal obstruction, and general symptoms of leukemia such as fever, night sweats, and weight loss. The disease can also involve the central nervous system (CNS), leading to neurological symptoms. Due to its aggressive nature, Burkitt's leukemia requires prompt diagnosis and treatment.

Diagnosis

The diagnosis of Burkitt's leukemia involves a combination of clinical evaluation, laboratory tests, and imaging studies. Laboratory tests may reveal anemia, thrombocytopenia, and elevated levels of lactate dehydrogenase (LDH), indicating rapid cell turnover. The definitive diagnosis is made through the histological examination of a biopsy specimen, which shows a characteristic "starry sky" appearance due to the presence of rapidly dividing tumor cells and scattered macrophages. Cytogenetic analysis or fluorescence in situ hybridization (FISH) is used to detect the c-MYC translocation.

Treatment

Treatment for Burkitt's leukemia typically involves intensive chemotherapy, which may include the use of multiple chemotherapeutic agents. Rituximab, a monoclonal antibody that targets the CD20 protein on the surface of B cells, may also be used in combination with chemotherapy. Due to the high risk of CNS involvement, prophylactic treatment to prevent CNS disease is commonly administered. The aggressive treatment approach can be effective, but it is also associated with significant toxicity and requires careful management of side effects.

Prognosis

The prognosis for Burkitt's leukemia has improved significantly with the advent of aggressive chemotherapy regimens. However, the outcome depends on several factors, including the stage of the disease at diagnosis, the patient's age, and the presence of CNS involvement. Early diagnosis and treatment are critical for achieving the best possible outcome.

Epidemiology

Burkitt's leukemia is most common in children and young adults, with a higher incidence in males than in females. The endemic form is prevalent in equatorial Africa and is associated with malaria and EBV infection. The sporadic form occurs worldwide but is less common. Immunodeficiency-related Burkitt's leukemia/lymphoma is seen in individuals with HIV/AIDS or those who are immunocompromised due to other reasons.