There was no difference in survival outcomes in patients with lung cancer with and without an existing autoimmune disease, according to the results of a retrospective study published in JAMA Network Open.1
“This finding is intriguing, given that fewer patients in the autoimmune cohort received standard-of-care lung cancer treatment,” the study authors wrote.
Lung cancer has been associated with some autoimmune diseases and mixed data have suggested that autoimmune disease may be associated with disease progression. The aim of this study was to understand the survival outcomes of patients with autoimmune disease and lung cancer.
The retrospective study evaluated data from 177 patients with lung cancer and an autoimmune disease treated at a single center between 2003 and 2019 (mean age at diagnosis, 67 years). A control cohort comprising 219 patients with lung cancer but no autoimmune disease was also included (mean patient age at diagnosis, 65.9 years). Most patients with and without an autoimmune disease had a prior smoking history (79.1% and 78.5%, respectively).
The most common lung cancer histology was adenocarcinoma, but this differed between groups, with 55.9% in the autoimmune cohort reported to have adenocarcinoma compared with 72.1% in the control cohort. Other histologies included squamous cell (16.4% vs 13.7%), large cell (1.7% vs 0.5%), not otherwise specified (7.6% vs 4.6%), small cell (9.6% vs 5.9%), and other (9.0% vs 3.2%).
The majority of patients in both cohorts had locoregional disease at diagnosis (autoimmune cohort, 62.7%; control group, 69.4%) followed by distant metastases (32.8% vs 29.2%). The remaining 4.3% of patients with an autoimmune disease had unstaged disease. In the control cohort, 1.4% of patients were found to have unstaged disease.
Standard-of-care (SOC) treatment was administered to 69.5% of patients in the autoimmune cohort. The primary reason for not receiving the SOC was poor initial performance status frailty (68.4%). The second most common reason why patients did not receive the SOC was comorbidities due to autoimmune disease (5.3%). Of note, patients in the control cohort were significantly more likely to receive SOC treatment (97.3%; P <.001).
Both progression-free survival (PFS) and overall survival (OS) were similar between the 2 cohorts. The median PFS for locoregional disease was 42.8 months in the autoimmune group compared with 34.0 months in the control group (P =.82). The median PFS for distant disease was 6.97 months and 8.77 months for the autoimmune and control subsets, respectively (P =.44).
Among patients with locoregional disease, the median OS was 48.4 months in the autoimmune cohort compared with 39.6 months in the control cohort (P =.83). For distant disease, the median OS was 9.96 months and 19.0 months for the autoimmune and control cohorts, respectively (P =.21).
“We observed no difference in lung cancer survival for patients with autoimmune disease compared with those in the control group,” the investigators concluded.
Although the authors of an accompanying editorial agreed with this conclusion, they noted, “it is unclear whether the results are generalizable to other patient populations, namely patients who receive care outside of an academic medical center.”2
Disclosures: One of the study authors disclosed financial relationships with the pharmaceutical industry and/or the medical device industry. For a full list of disclosures, please refer to the original study.
- Jacob S, Rahbari K, Tegtmeyer K, et al. Lung cancer survival in patients with autoimmune disease. JAMA Netw Open. Published online December 14, 2020. doi:10.1001/jamanetworkopen.2020.29917
- Volkmann ER. The association of autoimmune disease with lung cancer survival. JAMA Netw Open. Published online December 1, 2020. doi:10.1001/jamanetworkopen.2020.30506