[Risk factors for non-Hodgkin's lymphomas]

To divulge the risk factors for non-Hodgkin lymphomas (NHL) in children and adults among pediatricians.

We performed a literature review of articles published in the last 25 years through the Medline, IAR Cancer and Cancerlit databases. The search profile was "NHL risk factors". The most interesting papers, as well as the most relevant articles cited and published more than 25 years prior to the search, were selected.

The following risk factors for the development of NHL were reported with greater or lesser evidence: socioeconomic status, family factors, immunodeficiencies, bacterial and viral infections, vaccinations and drugs, radiation,occupational exposure, exposure to animals, diet, and lifestyle.

The etiology of most NHLs is unknown. The most important risk factors are: a) congenital and acquired immunodeficiency; b) viral (human T-cell leukemia virus type-I, Epstein-Barr virus, AIDS virus), and bacterial (Helicobacter pylori) infections; c) therapy with diphenylhydantoin and antineoplastic drugs, and d) exposure to pesticides and organic solvents.