The causes of lymphoma are unknown, but a series of risk factors have been established.
Problems associated with the immune system. Some people have a greater risk of developing lymphoma because their immune system does not work correctly, which is sometimes associated with one of the following reasons:
Medicines administered to prevent rejection after any type of organ transplant.
Genetic immune system diseases (normally diagnosed during childhood).
Autoimmune diseases. People whose immune system attacks their own cells, as in the case of Sjögren’s syndrome, Hashimoto’s thyroiditis and coeliac disease.
Infections. Some types of lymphoma are either directly or indirectly (due to chronic [over] stimulation of the immune system) produced by certain infectious agents. It is extremely important to remember that many of these infections are very common and the majority of people who suffer them do not present any risk of developing a lymphoma.
Epstein-Barr virus (EBV). EBV is associated with Burkitt’s lymphoma, some types of Hodgkin’s lymphoma and lymphomas in individuals with a dysfunctional immune system.
Human T-cell lymphotropic virus (HTLV-I). This virus is associated with adult T-cell leukaemia/lymphoma, but both the infection and the type of lymphoma are very uncommon in our population.
Human herpesvirus 8. This is associated with primary effusion lymphoma, which is often diagnosed in patients who have a dysfunctional immune system.
Hepatitis C virus. Associated with marginal zone lymphoma.
Helicobacter pylori. Associated with gastric lymphoma.
Chlamydia psittaci. Associated with lymphoma of the lagrimal gland.
Campylobacter jejuni. Associated with intestinal lymphoma.
Borrelia burgdorferi. Associated with lymphoma of the skin.
Previous treatment of another cancer. Chemotherapy and radiotherapy increase the risk of developing a lymphoma.
Old age. As with any cancer, the risk of developing a lymphoma increases with age because the body’s cells accumulate genetic abnormalities over the years while their ability to resolve them simultaneously diminishes.
There is no solid evidence that factors such as the use of chemicals (pesticides, dyes), smoking, diet, physical exercise or obesity increase or decrease the risk of lymphoma.