OBJECTIVES: The use of big data to assess the effectiveness of oncological treatments in clinical practice is gaining increasing interest. This analysis aimed to assess the overall survival of metastatic non-small cell lung (met-NSCLC) patients receiving chemotherapy (CT) or immunotherapy (I/O) as 1^st line by using real-world data in a sample population in Italy.

METHODS: A retrospective observational analysis based on administrative data from a sample of Italian Local Health Units was conducted. Met-NSCLC patients starting a 1^st line therapy with CT or I/O between 2017-2018 were identified. Stopping inclusion period up to 2018 enabled at least a two-years follow-up period for each included patient. Kaplan Meier overall survival analysis considered time (months) from therapy initiation to death. Multivariable analysis was performed to adjust for cofounders such as age, gender, metastasis, BRAF test prescription and pharmacological treatments.

RESULTS: A total of 3,126 (mean age±SD 68.6±9.8 years, 68.2% male) and 316 (mean age±SD 68.6±9.7 years, 74.4% male) patients initiated treatment with CT and I/O respectively. In both groups, the more frequent metastases detected were related to lymph nodes (42.1% CT, 24.1% I/O), bone (25.8% CT, 14.9% I/O) and brain (18.3% CT, 10.1% I/O). Median [95%CI] survival was 8.0 [7.4-8.6] and 14.6 [12.2-18.9] months for CT and I/O patients, respectively. Death was not reported in 31.2% of CT and in 44.3% of I/O cohorts. Multivariable analysis showed the risk of death to be significantly lower in patients treated with I/O compared to CT (HR [95%CI] 0.796 [0.681-0.930]).

CONCLUSIONS: Results from our study showed among met-NSCL patients in 1^stline a better overall survival of the I/O compared to CT patients and a reduced risk of death of I/O vs CT-treated patients. Our findings suggest real-world data could produce valuable insights into treatments and their outcomes in routine daily oncology practice, thus integrating the evidence from clinical trials.