Patients with autoimmune diseases—including rheumatoid arthritis (RA)—do not have poorer lung cancer survival compared to patients without autoimmune disease, but they are less likely to receive standard-of-care treatment, according to a study.
This was a retrospective cohort study of patients at a single academic center between 2003 and 2019. A total of 349 patients with lung cancer (small cell, adenocarcinoma, squamous cell carcinoma, non-small cell not otherwise specified, and large cell carcinoma) and autoimmune disease (RA, systemic lupus erythematosus [SLE], systemic sclerosis [SSc], mixed connective tissue disease, myositis, and Sjögren syndrome). Control patients had biopsy-confirmed lung cancer and did not have autoimmune disease.
Final analysis consisted of 177 patients with lung cancer and autoimmune disease. The mean age at the time of cancer diagnosis was 67 years (standard deviation [SD], 10 years), and three-quarters of patients were female (n=136 [76.8%]). RA was the most prevalent autoimmune disease (n=97 [54.8%]), followed by SSc (n=43 [24.3%]) and SLE (n=15 [8.5%]). Adenocarcinoma was the most prevalent lung cancer (n=99 [55.9%]), followed by squamous cell carcinoma (29 [16.4%]), and small cell lung cancer (17 [9.6%]). There were 219 control patients. The mean age at the time of cancer diagnosis was 65.9 years (SD, 4.1 years).
While overall survival did not differ between patients with versus without autoimmune disease (log-rank P=0.69), the autoimmune disease group was less likely to receive standard of care (n=126 [69.5%] vs. n=213 [97.3%]; P<0.001).
No autoimmune disease in particular appeared to be correlated with poorer prognosis.
The study was published in JAMA Network Open.
In an accompanying editorial, also published in JAMA Network Open, Elizabeth R. Volkmann, MD, MS, of the Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, wrote that, overall, “the present study provides compelling evidence that the existence of an autoimmune condition does not adversely affect survival in patients with lung cancer. Future studies are needed to evaluate whether specific immunomodulatory agents used to treat autoimmune conditions as well as the duration of immunomodulatory therapy affect lung cancer survival rates in these patients. The answers to these questions may help guide future therapeutic efforts in this area.”