46PEvolution of overall survival (OS) in patients (pts) with incident NSCLC in Denmark and Sweden: A SCAN-LEAF study analysis from the I-O Optimise initiative

Background: As part of I-O Optimise, a multinational research platform providing real-world insights into the management of lung cancers, the SCAN-LEAF study aims to describe the epidemiology, clinical care, and outcomes for pts with NSCLC in Scandinavia. Here, we report temporal OS trends among pts diagnosed with incident NSCLC from 2005 to 2015 in Denmark and Sweden. Methods: The SCAN-LEAF Danish and Swedish cohorts were established by linking respective national registries and include all adult pts diagnosed with incident NSCLC from Jan 2005 to Dec 2015 (follow-up to Dec 2016). The Kaplan–Meier method was used to estimate OS at 1, 3, and 5 yrs by histology (non-squamous cell [NSQ] or squamous cell [SQ]), TNM stage, and yr of diagnosis; changes in OS over time were assessed using the Cochrane–Armitage test. Results: 31,939 pts in Denmark and 30,067 pts in Sweden were diagnosed with NSCLC from 2005 to 2015. Most were diagnosed at stage IV (51.6% and 48.4%, respectively) and had NSQ histology (54.4% and 60.4%). Statistically significant trends (P 5% over the analysis period were seen for NSQ pts at 1 yr for all stages in both countries (Table); at 3 yrs for stages I–IIIB in Denmark (P ≤ 0.027), and stages I–II (P ≤ 0.0013) in Sweden; and at 5 yrs for stages I–II (P ≤ 0.026) in both countries. For SQ pts, this was seen only at 1 yr for stage IIIA in Denmark and stage I in Sweden (Table), and at 5 yrs for stage IIIA in Denmark (p = 0.02). Conclusions: Despite some improvements between 2005 and 2015, mainly in the short-term survival of pts with early-stage NSCLC, long-term OS rates for pts with late-stage disease did not change significantly and remained low. Even in pts with early-stage disease, OS outcomes were suboptimal, with a particular unmet need in the SQ population. Future analyses including data after 2015 will evaluate the potential impact on OS of increased use of new TKIs and immune checkpoint inhibitors.