Outcome analysis of immunotherapy and possible prognostic role of pretreatment neutrophil-lymphocyte ratio in lung cancer: An Appalachian study.

Abstract

e21053 Background: Immune checkpoint inhibitors (ICI) have revolutionized the treatment of lung cancer resulting in better survival benefits. We are reporting outcome analysis of lung cancer patients treated with ICI in our institution. Methods: We performed retrospective chart review of lung cancer patients treated with ICI at our institution between June 2016 and March 2022. Results: A total of 289 patients were identified- 241 had non-small cell lung cancer (NSCLC) and 48 had small cell lung cancer (SCLC). A total of 109 patients (37.7%) developed immunotherapy related adverse events (IRAE): 92 (38.1%) with NSCLC and 17 (35.4%) with SCLC. Average time to develop IRAE was 3 months in both NSCLC and SCLC. IRAE grades 1,2,3,4 were noted in 33%, 20%, 15%, 31% patients respectively. 34 of 63 (53%) patients who received Ipilimumab-Nivolumab developed more IRAE than any other ICI with fatigue and dermatitis being the most common IRAE associated with this ICI. 79 of 183 (43%) patients who received RT developed IRAE (p = 0.012). Median overall survival (OS) for NSCLC was 35 months, 41 months, 27 months, 15 months for stages 1,2,3,4, respectively (p = 0.03). Median OS for extensive stage SCLC was 14.6 months. Median OS for NSCLC with and without IRAE was 30 and 23 months, respectively (p = 0.02). Median OS for SCLC with and without IRAE was 16.7 and 16.2 months, respectively (p = 0.5). Median OS for NSCLC when steroids were used to treat IRAE was 25 months, and 63 months if no steroids were used (p = 0.027). Better median overall survival rate was noted in patients with low Neutrophil-Lymphocyte ratio (defined as NLR < 5) 29.23 months vs 20.59 months (high NLR) (p = 0.019). Although demographics like male sex, smoking history, higher BMI and poor ECOG performance status had numerically increased the risk of developing IRAE, no statistical significance was noted. Conclusions: Overall results of our analysis are mostly consistent with the current literature on survival rates in Lung Cancer. IRAE may have a predictive role in survival, as we observed that patients with NSCLC developing IRAE had better survival rates. Ipilimumab-Nivolumab combination resulted in more IRAE than any other ICI. Pneumonitis was the most common IRAE among all patients receiving ICI. Also, Radiation-therapy increased the risk of developing IRAE. Our observation that steroid use in treating IRAE was associated with lower survival is concerning. This may be due to higher grade IRAE/toxicities and possible decreased ICI effectiveness. Regardless of IRAE, low pretreatment NLR resulted in better survival rates. The role of pretreatment NLR as a potential prognostic tool to assess survival outcomes requires validation in a randomized clinical trial.