Impact of Comorbidity Scores on the Overall Survival of Patients With Advanced Non-small Cell Lung Cancer: A Real-World Experience From Eastern India

Introduction Lung cancer is the most common cancer, and it is the leading cause of cancer-related death. Smoking is the most common risk factor for the development of lung cancer. There is a lack of data on the comorbidities and outcomes of advanced non-small cell lung cancer (NSCLC) in the eastern part of India. This prospective study evaluated the impact of comorbidity scores on overall survival (OS) in these patients. Method This prospective cohort study was conducted on newly diagnosed advanced NSCLC patients between June 2020 and April 2021. These patients were given platinum-based doublet chemotherapy guided by histology and targeted therapy based on molecular studies. Comorbidities were assessed using the Charlson Comorbidity Index (CCI), Simplified Comorbidity Score (SCS), and Adult Comorbidity Evaluation-27 (ACE-27). The outcome assessed was OS. Overall survival was calculated in days from the date of start of anticancer therapy to the date of last follow-up or date of death. All enrolled patients were followed at regular intervals whenever they visited the hospital and telephonically until April 2022. The patients who were alive on April 30, 2022, were censored. The survival probability and median OS were calculated by Kaplan-Meier analysis, and group differences in comorbidity scores were analyzed with the log-rank test. A Cox proportional hazard analysis was performed to look for factors affecting overall survival. Results A total of 114 patients were enrolled in the study period, and the mean age of patients was 56.54 ± 11.03 years. Most of the patients were males (68.4%), and 52.6% were smokers. Adenocarcinoma was the most common histology (73.7%), followed by squamous cell carcinoma (25.4%). The median OS was 127 days (95% CI, 60-193 days). 33.4% of the patients had a CCI score of 0, a CCI score of 1 was seen in 57%, and ≥2 scores in 9.6%. SCS scores ≤9 and >9 were seen in 92.1% and 7.9% of patients, respectively. The ACE-27 score was none in 41 subjects, mild in 59, moderate in 12, and 2 NSCLC subjects had severe ACE-27 scores. The median OS for patients with a CCI score of 0 was 275 days (95% CI, 7-543 days), 114 days (95% CI, 85-142 days) for subjects with a CCI score of 1, and 402 days (95% CI, 0-844 days) for patients with a CCI score ≥2 (log-rank p = 0.215). Individuals with an SCS score ≤9 had a median OS of 175 days (95% CI, 91-258 days), and the median OS was 92 days (95% CI, 80-103 days) for patients with an SCS score >9 (log-rank p = 0.302). Median OS of the patients with ACE-27 score 0,1,2,3 were 297 days (95% CI, 76- 517 days), 117 days (95% CI, 81-152 days), 87 days (95% CI, 49-124 days) and 66 days, respectively (log-rank p=0.457). There was no statistical significance between comorbidity scores and OS. Worse OS was independently associated with poor performance status Eastern Cooperative Oncology Group (ECOG) ≥2 (hazard ratio [HR] 3.266; 95% CI 1.785-5.978; p = 0.00), neutrophil-to-lymphocyte ratio (NLR) <3 (HR, 2.35 95% CI 1.18-4.702; p = 0.015) and patients who were given compassionate tyrosine kinase inhibitors (TKIs) (HR, 7.396 95% CI 3.531-15.490; p = 0.000). Conclusions In our study, the advanced NSCLC patients who were given chemotherapy or oral TKIs showed no significant influence of comorbidities on overall survival. Factors independently associated with the worst survival were poor performance status (ECOG ≥ 2), NLR < 3, and patients who were given TKIs on a compassionate basis.