Non-Hodgkin’s Lymphoma in the Context of Antecedent Rheumatoid Arthritis: A Case Series from the Mayo Clinic and the Nebraska Lymphoma Study Group.

PURPOSE: Rheumatoid arthritis (RA) has been associated with an increased risk of non-Hodgkin’s lymphoma (NHL). We describe the characteristics of NHL patients with antecedent RA.

METHODS: Records of the Nebraska Lymphoma Study Group (NLSG) registry between 1982–2004 and the Mayo Clinic lymphoma registry between 1988–1998 were systematically reviewed for RA diagnosis and classified by the quality of supporting evidence. We abstracted available follow-up data through July 1, 2004. Definite cases had either a documented RA diagnosis from a trained rheumatologist or met 4 of 7 American College of Rheumatology criteria. Probable RA cases had a non-rheumatologist diagnosis of RA in addition to one of the following: 1) radiographic joint erosions; 2) disease-modifying anti-rheumatic drug (DMARD) use or; 3) RA-associated deformities (i.e., ulnar drift, swan-neck deformities). Five-year overall survival (OAS), event-free survival (EFS), and rates of treatment response were determined.

RESULTS: We identified 74 RA cases (54 definite and 20 probable) with concomitant NHL. These patients had a mean age of 67 + 8 years and were predominantly Caucasian (82%) and female (64%). Of the probable RA cases, a majority had documented DMARD use (n=17). Approximately half of the cases used methotrexate (55%) and were deceased (52%) by the common closing date. The most common NHL subtypes included B-DLCL (n=31), B-FL-1/B-FL-2 (n=12), B-FL-3 (n=6), and B-BL/B-BLL (n=4). Of the remaining 21 cases, most were of B-cell origin (n=13) and included B-EMZL (n=3), B-LPL (n=3), B-UCL (n=2), B-UCL-LG (n=2), B-DFL-2 (n=1), B-MCL (n=1), and B-SLL (n=1). The remaining NHL subtypes included NHL-NOS (n=7) or T-PTCL-LC (n=1). B-symptoms were present for 6 (19%) patients with B-DLCL and none of the patients with B-FL-1/B-FL-2. Complete response rates to NHL treatment were 48% in B-DLCL and 33% in B-FL-1/B-FL-2. For B-DLCL and B-FL-1/B-FL-2, respectively, the five-year OAS was 54% (95% CI 36%–69%) and 65% (95% CI 31%–85%) while the five-year EFS was 48% (95% CI 36%–69%) and 56% (95% CI 24%–79%). For all NHL cases the 5-year OAS was 58% (95% CI 47%–69%) and the 5-year EFS was 49% (95% CI 37%–59%).

CONCLUSIONS: Lymphomas developing in the context of RA most often include diffuse large B-cell and follicular subtypes. Complete response rates to standard treatment for these major subtypes ranged from 33 to 48%. For RA patients developing NHL, five-year overall- and event-free survival rates are approximately 50%.