Dear Doctor: Could you tell me about the causes, treatment and remission rates for Burkitt lymphoma?
Advertisement
Dear Reader: Burkitt lymphoma is a highly aggressive, rapidly growing type of B cell lymphoma. It's caused by an alteration to a gene involved with cell division and cell death. The alteration of this gene causes B cell lymphocytes (a type of white blood cell) to divide quickly and repeatedly, creating multiple abnormal cells.
There are three types of Burkitt lymphoma, and the likelihood of each one depends on your geographic region and your immune status. In Africa, the incidence of Burkitt lymphoma is 50 times higher than in the United States, with the disease there caused largely by chronic Epstein-Barr virus infection. In this type of Burkitt lymphoma, the peak incidence of infection is between the ages of 4 and 7. Often, the disease is initially found in the bones of the face or jaw; from there it can spread to other parts of the body.
The most common type of Burkitt lymphoma in the United States is much rarer -- about three cases per million people per year -- and the peak incidence is about 11 years of age, with the majority of cases occurring in people younger than 35.
The third type of Burkitt lymphoma occurs in people with a suppressed immune system, usually due to HIV infection. In these cases, the suppression of the immune system causes viruses, like Epstein-Barr, to exert genetic changes on B cells that lead to lymphoma.
Because Burkitt lymphoma is a rapidly growing cancer, chemotherapy works well against it, and multiple drugs are available to stop its growth and destroy the rapidly growing B cells. In fact, because drugs are so effective, radiation and surgery are not generally recommended. Of note, many chemotherapy regimens now include the medication Rituxan, often used for rheumatoid arthritis, because of its ability to attack B lymphocytes. Because Burkitt lymphoma can often make its way to the brain, most chemotherapy treatments are also given via the cerebrospinal fluid by way of a lumbar puncture.
Chemotherapy is not without its side effects. Part of the difficulty in older adults, especially those over the age of 60, is the ability to tolerate these side effects. They include bone marrow suppression, in which the numbers of red and white blood cells and platelets drop dramatically. The drop in the white blood cells can make a patient more susceptible to severe bacterial infections. Chemotherapy can also lead to toxicity of the heart and the nerves of the body.
As for survival rates, those depend on the regimen of chemotherapy and the age of the patient. A study from Germany found that people ages 15 to 25 had a five-year survival rate of 90 percent; the rate decreased to 84 percent in people ages 26 to 55, and to 62 percent in those over 55.
You didn't say whether you or someone you know is being treated for Burkitt lymphoma, but, if so, I hope this limited review has been helpful.
(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)