Burkitt's lymphoma is one of a group of more than 20 distinct diseases which are collectively known as non-Hodgkin's lymphoma (NHL).
Burkitt's lymphoma primarily affects children, although occasionally is also seen in young adults, particularly those under the age of 35. It is very much a disease of reduced immunity, and for this reason it is also seen increasingly in people who, because of HIV/AIDS, or because of immunosuppressive therapy, have a compromised immune system.
Burkitt's lymphoma was named for a British missionary surgeon, Denis P. Burkitt, who worked for many years in East Africa. In 1958, he speculated that the common childhood tumors he was seeing, endemic to the Central and Eastern parts of equatorial Africa, might have a viral origin.
Burkitt had observed that regions in which this kind of lymphoma was endemic were also those where malaria was widespread. He reasoned that some agent was spreading lymphoma via a mosquito, as happens with malaria.
He sent pathologic materials back to England where they were studied by Dr. Anthony Epstein, Y.A. Barr, and colleagues. These scientists managed to establish cell lines of the tumors and in some of them they found herpes-like viral particles. This virus is now commonly known as Epstein-Barr virus.
Epstein-Barr (EB) virus is the virus that causes glandular fever or infectious mononucleosis ("mono"). This is a relatively common infection which, in otherwise healthy individuals, resolves itself and does not lead to anything more serious than a period of convalescence. It is important to note that the majority of adults in the world have antibodies to the Epstein Barr virus. So, obviously, not every case of EBV infection leads to cancer. However, in those who have been weakened by a concurrent infection, such as HIV or malaria, and whose immune systems are compromised by that struggle, EB virus seems to be capable of transforming B-lymphocytes into malignant (i.e., lymphoma) cells. The cases of Burkitt's lymphoma seen by Denis Burkitt in equatorial Africa were all of this type, and for this reason, this kind of lymphoma is called classical African or endemic Burkitt's lymphoma.
Much is now known about the manner in which the virus disrupts chromosomes, particularly certain regions on chromosomes 8 and 14. Burkitt's lymphomas also often contain mutations of the p53 gene, which may offer a treatment opportunity in the future.
However, in the US the non-African, or sporadic type of Burkitt's lymphoma is the type most commonly seen, and this type affects not only children but also adults, particularly those in whom the immune system is already compromised. A subtype of sporadic Burkitt's is Burkitt-like lymphoma (BLL).
In the United States, Burkitt's lymphoma affects a somewhat older population and about 75 percent of affected people have abdominal tumors. In fact, it is generally first seen in the abdomen, with massive disease and the build-up of ascites fluid. Like the African form, it can also spread to the bone marrow and the central nervous system. Adult cases are often associated with AIDS. and may be seen with associated acute leukemia and circulating Burkitt's lymphoma cells (called L3-ALL). Such immunocompromised patients are classified as having an immunodeficiency associated variant of Burkitt's.
