Patients with longstanding rheumatoid arthritis have been shown to have an increased risk for non-Hodgkin lymphoma in large population-based studies. The mechanism is thought to be related to chronic inflammation and the resultant chronic antigenic stimulation of B-cells by rheumatoid factors, which leads to an increased risk for B-cell transformation. Methotrexate treatment has also been implicated in the development of lymphoma in patients with rheumatoid arthritis, but this has been contested in more recent work.
The Epstein-Barr virus has also been implicated in the past. Recent work, however, suggests that it may only be associated with an increased risk of Hodgkin lymphoma.
The images above are from a patient with longstanding rheumatoid arthritis who developed B-cell lymphoma. The radiograph of the hand reveals severe joint space narrowing and erosions and subluxations that predominantly involve the radiocarpal, intercarpal, and carpometacarpal joints. Axial CT image in mediastinal window reveals an enlarged left internal mammary lymph node (pink arrow). Lung windows reveal multiple pulmonary nodules (blue arrows) in a