Study reveals higher mortality risk from lung and hematologic neoplasms in rheumatoid arthritis patients

A nationwide observational study from Spain published in Medicina Clínica has highlighted a significantly higher mortality risk from lung and hematologic neoplasms in patients with rheumatoid arthritis (RA) compared to the general population. The findings, based on data from the Spanish Hospital Discharge Database, analyzed 139,531 cancer-related deaths between 2016 and 2019, including 813 (0.6%) among RA patients. 

The study reported that while RA patients had a lower mortality rate from solid organ neoplasms (SON) overall (85.1% vs. 91.2%), they were more likely to die from lung cancer (20.2% vs. 18.6%, OR 1.31). Conversely, deaths from colorectal carcinoma (8% vs. 10.6%, OR 0.67) and hepatocarcinoma (1% vs. 2.7%, OR 0.44) were less common in this group. Hematologic neoplasms (HN) accounted for a greater proportion of deaths in RA patients (14.9% vs. 8.8%, OR 1.73). The most pronounced risks were linked to B and T/NK non-Hodgkin lymphomas (6% vs. 2.8%, OR 2.12) and myeloid leukemia (4.4% vs. 2.3%, OR 1.92). 

Due to the complex connection between the hematologic and immune systems, the risk of hematologic malignancies in patients with RA remains a significant clinical concern. Several autoimmune conditions, including RA, are associated with an elevated risk of both myeloid and lymphoid neoplasms. Specifically, RA has been linked to a higher likelihood of developing acute myeloid leukemia (AML), myelodysplastic syndrome, non-Hodgkin lymphoma, and Hodgkin lymphoma. Various factors have been implicated in amplifying this risk. Treatments such as methotrexate and anti-tumor necrosis factor α (TNF-α) inhibitors, as well as heightened disease activity, have been identified as contributors. Additionally, infections such as Epstein–Barr virus (EBV) have been reported to play a role in the increased incidence of lymphoma among RA patients. This underscores the importance of understanding these associations to enhance risk management and patient care. 

A study by Lin et al. reported elevated risk of hematologic malignancies in patients with RA, with notable differences observed based on gender and malignancy type. Male RA patients demonstrated significantly higher incidences of both lymphoid (SIR 3.36) and myeloid malignancies (SIR 3.69) compared to RA-free controls. Female RA patients showed an increased incidence of lymphoid malignancies (SIR 3.00) but did not have a statistically significant rise in myeloid malignancies (SIR 1.54). Moreover, RA patients experienced a significantly shorter interval between RA diagnosis and the development of hematologic malignancies compared to RA-free individuals, with follow-up durations of approximately 70.70 months for males and 67.73 months for females, versus over 100 months in controls. Male RA patients also exhibited higher cumulative hazard rates for both lymphoid and myeloid malignancies. 

The findings emphasize the need for targeted interventions, including early cancer detection and strategies to manage the immunosuppressive therapies often used in RA treatment. Researchers highlight the importance of understanding the relationship between RA, its treatments, and cancer risk to improve patient outcomes. 

 References 

  1. Esteban-Sampedro J, Moreno-Torres V, Martín-Portugués M. Higher mortality risk from lung and hematological neoplasms in patients with rheumatoid arthritis: An observational study from the Spanish National Registry. Med Clin (Barc). 2025 Jan 24;164(2):69-72. 
  2. Lin YC, Chou HW, Tsai WC, Yen JH, Chang SJ, Lin YC. The age-risk relationship of hematologic malignancies in patients with rheumatoid arthritis: a nationwide retrospective cohort study. Clin Rheumatol. 2015 Jul;34(7):1195-202.