Real-world outcomes of immune checkpoint inhibitors in patients aged 65–74 versus ≥75 years with non-small cell lung cancer.

Abstract

e20642 Background: Immune Checkpoint Inhibitors (ICIs) have shown significant survival benefit in the treatment of Non-Small Cell Lung Cancer (NSCLC). However, adults ≥75 years, remain under-represented in clinical trials despite comprising a growing proportion of patients with cancer and are often grouped as “older adults” (≥65 years), which may overlook age related physiological and pathophysiological complexity. Methods: We conducted a multicenter retrospective cohort study using the TriNetX network to compare real-world ICI outcomes in patients aged 65–74 years with those ≥75 years. Inclusion criteria included ICD 10-code for malignant neoplasm of the bronchus and lung, and treatment with pembrolizumab, nivolumab, cemiplimab, atezolizumab, durvalumab, and/or ipilimumab. Exclusion criteria consisted of patients on chemotherapy and those with small cell lung cancer, neuroendocrine tumors, carcinoid tumors, hematological/lymphoid malignancies, ulcerative colitis, Crohn’s disease, microscopic colitis, and history of organ transplant. There is no specific ICD-10 code for NSCLC, but these cohorts aim to reflect real-world NSCLC treatment regime, as ICIs are not routinely used in small cell lung cancer. Patients were divided into two cohorts: 65–74 years (Cohort 1) and ≥75 years (Cohort 2). Index date was defined as the first documented ICI administration. Propensity score matching (1:1) was performed on demographic variables, measure of association analysis was used to calculate outcome proportions and survival outcomes were analyzed using Kaplan-Meier analysis. Primary outcome was all-cause mortality. Secondary outcomes included ICU admission, systemic corticosteroid initiation, incidence of pneumonitis, gastrointestinal colitis, hepatitis, myocarditis, and ICD-10 code adverse effects of ICI (T45.AX5 A/D/S). Results: After propensity score matching, each cohort included 4,300 patients. All-cause mortality was significantly lower in patients aged 65-74 compared to those ≥75 years (41.2% vs 51.5%). Risk Difference (RD) was −10.3% (95% CI −0.124 to −0.082; p < 0.001), and odds ratio was 0.660 (95% CI 0.606–0.718). Gastrointestinal colitis/enterocolitis occurred more frequently in patients 65–74 than in those ≥75 years (9.7% vs 7.9% - RD of 1.8% 95% CI 0.006-0.030%; p = 0.003). No significant differences were observed in ICU admission, pneumonitis, myocarditis, systemic corticosteroid initiation, or ICD-10–coded ICI adverse effects. Conclusions: The higher rate of mortality in patients aged ≥75 years with NSCLC treated with ICIs but with lower rates of gastrointestinal colitis/enterocolitis, highlights the heterogeneity and complexity in outcomes in the older adult population. Due to increasing proportion of geriatric patients among individuals with cancer, focus on age-stratified research may improve prognostication and guide treatment plans.