Session Item

Healthcare administrative datasets represent a valuable source for real-life data analysis.  In the current work data on more than 10 million individuals resident in Lombardy Region (Northern Italy) were considered. Primary aim is to compare safety and effectiveness in a non-small cell lung cancer (NSCLC) patients who received different patterns of first-line systemic therapy with or without RT.

Diagnostic ICD-9-CM codes were used for identifying all patients with a new diagnosis of lung cancer between 2012 and 2019. Among these, patients who started a systemic non-chemotherapy as first-line of treatment for advanced NSCLC alone or in combination with radiotherapy (RT). Since the same code is applied to NSCLC and SCLC, systemic treatment (ST) considered were tyrosine-kinase inhibitors (TKI) or pembrolizumab as drugs exclusively administered in NSCLC. RT treatments were limited to SBRT and IMRT, in order to select patients with a better expected prognosis. Patients were followed from the date of first-line treatment start until 31^st December 2020. Overall survival (OS) was estimated by using the Kaplan-Meier estimator and differences between groups were compared using the log-rank test. Hazard ratios, along with 95% confidence intervals (CI) were estimated using Cox proportional hazards models adjusted for sex, age, year of first-line treatment start and a cancer multimorbidity score. Analyses were stratified by type of first-line ST and diagnosis of brain metastasis.

During the study period, 95 patients were treated with ST + RT, and 1873 with ST alone. After a median follow-up of 13.3 months, median OS was 20.2 and 16.8 months (p= .348), respectively, in the two groups. Among 1714 patients without brain metastasis (BM), similar patterns of OS were observed in patients treated with ST + RT, as compared to those treated with ST alone, being the median OS 21.9 and 18.5 months (p= .488), respectively. Conversely, patients with BM (n= 254) treated with RT exhibited a significant greater OS as compared to those treated with ST alone, being median OS 21.3 and 7.6 months (p< .001), respectively, corresponding to an adjusted HR of 0.48 (95% CI 0.32-0.70). This reduction in the risk of death was greater in patients treated with first-line TKI (adjusted HR= 0.45, 95% CI 0.26-0.76), while in the smaller sample of those treated with first-line Pembrolizumab was not statistically significant (adjusted HR=0.74, 95% CI 0.37-1.50) (Figure 1).

Real-world data represent a new reality to complement evidence from controlled randomized clinical trials. The current work represent an exploratory study and analyses on the second line therapy will follow. Our data suggest that in patients with a worse prognosis, as the ones with BM, RT brings an effective advantage in terms of OS that should be considered in clinical practice.