RECENT DATA ON THE EPIDEMIOLOGY OF NON-HO DGKINS-LYMPHOMA

Non-Hodgkin's lymphoma is a common condition whose incidence has incre ased by 75 % over the last 15 years. The HIV epidemic is among the fac tors that have contributed to this increase : patients with AIDS have 1% annual risk of developing non-Hodgkin's lymphoma, and the increase in survival of AIDS patients has led to an increase in the frequency o f AIDS-associated lymphomas. A number of other viruses are directly in volved in the occurence of lymphomas, such as the HTLV-1 and the EBV: The HSV type 8 has recently been incriminated in the occurence of lymp homas located in the cavities of the body. The role of the hepatitis C virus in the occurence of lymphoma is controversial. Inherited or acq uired immunodeficiencies (e.g., due to treatment for an autoimmune dis ease or transplant) are associated with an increased incidence of lymp homa. The role of toxic chemicals, especially those used in farming, i s receiving increasing attention. A number of infectious diseases prom ote the occurence of lymphomas; the best illustration of this link is the association between Helicobacter pylori and primary low-grade gast ric lymphomas.