Certain autoimmune and chronic inflammatory conditions, such as Sjögren's 
syndrome and rheumatoid arthritis (RA), have consistently been associated with 
an increased risk of malignant lymphomas, but it is unclear whether elevated 
lymphoma risk is a phenomenon that accompanies inflammatory conditions in 
general. Likewise, it is debated whether the increased risk identified in 
association with some disorders pertains equally to all individuals or whether 
it varies among groups of patients with different phenotypic or 
treatment-related characteristics. It is similarly unclear to what extent the 
increased lymphoma occurrence is mediated through specific lymphoma subtypes. 
This update reviews the many findings on risks, risk levels, and lymphoma 
characteristics that have been presented recently in relation to a broad range 
of chronic inflammatory, including autoimmune, conditions. Recent results 
clearly indicate an association between severity of chronic inflammation and 
lymphoma risk in RA and Sjögren's syndrome. Thus, the average risk of lymphoma 
in RA may be composed of a markedly increased risk in those with most severe 
disease and little or no increase in those with mild or moderate disease. The 
roles of immunosuppressive therapy and EBV infection seem to be limited. 
Furthermore, RA, Sjögren's syndrome, systemic lupus erythematosus, and possibly 
celiac disease may share an association with risk of diffuse large B-cell 
lymphoma, in addition to well-established links of Sjögren's syndrome with risk 
of mucosa-associated lymphoid tissue lymphoma and of celiac disease with risk of 
small intestinal lymphoma. However, there is also obvious heterogeneity in risk 
and risk mediators among different inflammatory diseases.