Burkitt Lymphoma

Burkitt lymphoma is a rare but highly aggressive form of non-Hodgkin lymphoma (NHL), a type of blood cancer derived from a group of white blood cells called lymphocytes.   

All lymphomas arise from lymphocytes, specifically B-cells and T-cells, which mainly live in the lymph nodes and move through the blood and lymphatic system. Generally speaking, lymphomas can be categorized into two main groups: Hodgkin lymphoma and non-Hodgkin lymphoma, where “non-Hodgkin” refers to the absence of the Reed-Sternberg cell, a characteristic cell found in Hodgkin lymphoma.  

One known cause of Burkitt lymphoma is a chromosomal translocation between chromosome 8 and chromosome 14. In the translocation, a part of chromosome 8 containing an oncogene called MYC is switched for a part of chromosome 14 that is next to a promoter region of the chromosome, thereby resulting in overexpression of MYC. The MYC gene stimulates cell growth and metabolism, so this translocation results in uncontrolled cell division. 

There are three types of Burkitt lymphoma: endemic, sporadic, and immunodeficiency-related Burkitt lymphoma. Endemic Burkitt lymphoma is one of the most common childhood cancers in equatorial Africa and is almost always associated with Epstein-Barr virus (EBV) infection. EBV is a common and highly contagious infection that is primarily transmitted through the saliva. EBV is able to infect lymphocytes and can incorporate its genetic material into a host’s cell DNA, however, exactly how EBV infection causes lymphoma is still unclear. On the other hand, sporadic Burkitt lymphoma can occur in both children and adults worldwide and is the most common subtype in the United States and Western Europe. Unlike the endemic form, it is less commonly associated with EBV infection. Finally, immunodeficiency-related Burkitt lymphoma usually affects individuals with human immunodeficiency virus (HIV) infection but may also occur in people who take immunosuppressive medications (e.g., corticosteroids, cyclosporin, tacrolimus) to prevent organ transplant rejection.  

Burkitt lymphoma can present with symptoms such as low-grade fever, night sweats, and unintentional weight loss. Most lymphomas also cause enlargement of the lymph nodes, leading to palpable lumps that can be felt throughout the body, including the neck, armpit, or groin area.  

In addition, Burkitt lymphoma also typically causes extranodal involvement, meaning it can affect other parts of the body in addition to lymph nodes. For example, individuals with endemic Burkitt lymphoma classically present with fast-growing, painless, jaw tumors. On the other hand, sporadic Burkitt lymphoma is characterized by extranodal involvement of the abdomen, most often at the ileocecal junction, which is a part of the small bowel rich in lymphoid tissue.  

Burkitt lymphoma can also spread to the brain and spinal cord, especially in individuals with the immunodeficiency-related subtype, which can result in headaches, vomiting, altered level of consciousness, and weakness or loss of sensation.  

If there’s involvement of the bone marrow, cancer cells can crowd the bone marrow progenitor cells and decrease the production of healthy red blood cells, white blood cells, and platelets, causing symptoms like fatigue, recurrent infections, or easy bruising.

Finally, individuals diagnosed with Burkitt lymphoma are at risk of developing tumor lysis syndrome, a condition that occurs when a large number of cancer cells die in a short period of time, releasing a massive amount of breakdown products into the blood. Tumor lysis syndrome can affect various organs, causing symptoms like nausea and vomiting, muscle cramps, dark urine or decreased urine output, and heart palpitations. It is most common within a week of starting cancer treatment when the tumor burden is higher and cancer cells begin to die. 

Treatment for Burkitt lymphoma depends on various factors, including the age of the individual, stage, and prognostic factors of the lymphoma. Generally, treatment involves short-course intensive chemotherapy regimens in combination with rituximab, a monoclonal antibody that binds to the surface of B-cells inducing cell death. In individuals with HIV, treatment also includes antiretroviral therapy (ART), in addition to chemotherapy.  

Despite its aggressive nature, Burkitt lymphoma usually responds well to chemotherapy and has a high cure rate. Involvement of the central nervous system is one of the main risk factors for relapse and usually confers a worse prognosis. For this reason, most treatment regimens also include intrathecal chemotherapy, a special form of chemotherapy that is injected directly into the cerebrospinal fluid. For refractory or relapsed Burkitt lymphoma, a bone marrow transplant from a healthy donor may be used to slow down the progression of the disease. 

Finally, individuals with Burkitt lymphoma may be given supportive treatment to prevent tumor lysis syndrome during the duration of chemotherapy. Medications like allopurinol and rasburicase may be given to help reduce uric acid levels in the blood, and intravenous fluids may be administered to help flush toxins into the urine.