RESUMO
Background: Immunotherapy response rates in metastatic non-small cell lung cancer (NSCLC) are low and survival varies significantly. Factors like age, sex, race, and histology may modulate immunotherapy response. Existing analyses are limited to clinical trials, with limited generalizability, and meta-analyses where adjustment for potential confounders cannot be performed. Here, we conduct a cohort study with patient-level analysis to explore how personal and clinical characteristics moderate chemoimmunotherapy effectiveness in metastatic NSCLC. Methods: Stage IV NSCLC patients diagnosed in 2015 were drawn from Surveillance Epidemiology, and End Results-Medicare linked data. Receipt of chemoimmunotherapy and overall survival (OS) were the primary predictor and outcome of interest respectively. Multivariable Cox-proportional hazards regression and propensity-score matching were performed to evaluate the effectiveness of immunotherapy addition to chemotherapy. Results: From a total of 1,471 patients, 349 (24%) received chemoimmunotherapy and 1,122 (76%) received chemotherapy alone. Survival was significantly better among those treated with chemoimmunotherapy compared to those receiving chemotherapy alone [adjusted hazard ratio (HRadj) =0.72, 95% confidence interval (CI): 0.63-0.83]. Males saw significantly better OS from chemoimmunotherapy (HRadj =0.62, 95% CI: 0.51-0.75) than females (HRadj =0.81, 95% CI: 0.65-1.01, Pinteraction=0.0557). After propensity-score matching, the effect of chemoimmunotherapy was borderline significant according to sex (Pinteraction =0.0414), but not age or histology. Conclusions: Males may benefit more from chemoimmunotherapy, but there is limited evidence suggesting age, histology, race, and comorbidities contribute to differences in effectiveness. Future research should elucidate who responds best to chemoimmunotherapy, and further analyses of characteristics like race can inform how to tailor different treatment regimens to distinct patient subpopulations.
RESUMO
BACKGROUND: Metastatic non-small cell lung cancer (NSCLC) has many comorbidities, such as chronic obstructive pulmonary disease, coronary heart disease, and older age-related comorbidities. A survival benefit was observed in such patients who underwent surgery for selected oligometastatic disease. However, to the best of our knowledge, there is no evidence to support whether lobectomy (compared with sub-lobar resection) would further prolong these patients' lives. METHODS: Patients with metastatic NSCLC who underwent primary tumor resection were identified from the Surveillance, Epidemiology, and End Results (SEER) database and then divided into lobectomy and sub-lobar resection groups. Propensity score matching (PSM, 1:1) was performed to match the baseline characteristics of the two groups. Cancer-specific survival (CSS) was estimated. RESULTS: In total, 24,268 patients with metastatic NSCLC were identified; 4,114 (16.95%) underwent primary tumor surgery, and of these, 2,045 (49.71%) underwent lobectomy and 1,766 (42.93%) underwent sub-lobar resection. After PSM, 644 patients in each group were included. Lobectomy was independently correlated with longer median CSS time [hazards ratio (HR): 0.70, 95% confidence interval (CI): 0.61-0.80, P<0.001]. The 1, 2, and 3-year survival rates after PSM also favored the lobectomy group. However, no significant survival difference was found for wedge resection and segmentectomy (HR: 0.96, 95% CI: 0.70-1.31, P=0.490). The 1-, 2-, and 3-year survival rates after PSM also exhibited no difference within the sub-lobar group. We explored whether lymph node dissection would provide additional survival benefits for stage IV NSCLC patients. According to the multivariate Cox analysis of the matched population, lymph node dissection was independently associated with better CSS (HR: 0.76, 95% CI: 0.66-0.88, P<0.001) and overall survival (OS) (HR: 0.74, 95% CI: 0.65-0.86, P<0.001). We confirmed this result in the different types of surgery and found that the lymph node dissection group consistently had better survival outcomes both in the lobectomy group and sub-lobar resection population. According to the subgroup analysis, with the exception of stage T4 and brain metastatic patients, all of the patient subtypes exhibited greater benefit from lobectomy than sub-lobar resection. CONCLUSIONS: Lobectomy has a greater survival benefit in metastatic NSCLC patients compared with sub-lobar resection when radical treatment of primary site was indicated.