11178 Background: Detecting disease at an early stage is critical to improving lung cancer (LC) survival, as reflected in guidelines recommending screening with low dose computed tomography for individuals at high risk by clinical societies including the NCCN (2011) and US Preventive Services Task Force (2013, updated 2021). Presenting stage distribution may also be impacted by healthcare utilization changes following the COVID-19 pandemic. Real-world data (RWD)-based investigations are important complements to national cancer registries to provide insight into this potentially changing diagnostic landscape, especially given utilization, practice and referral patterns unique to community settings. We thus assessed LC stage from 2013-23 in a large, nationally representative sample of community oncology practices leveraging RWD. Methods: This is a retrospective observational cohort study of patients within The US Oncology Network and non-Network practices, which include a nationally representative network of over 3,700 providers and more than 1 million patients seen annually in community-based oncology practices. All adult (≥18 years) patients diagnosed with non-small cell LC (NSCLC) or small-cell LC (SCLC) who had a first observed stage available in the community oncology setting within 2013 to 2023 were included. Demographics and medical history data were sourced from structured data fields in iKnowMed, an oncology-specific electronic health record system. Time trends of patient diagnosis and characteristics were descriptively evaluated. Results: The analysis included 98,806 patients with LC (84,023 [85.0%] NSCLC and 14,783 [15.0%] SCLC). Approximately half were female (49.7% and 50.3% in each disease), three-fourths were White (72.7% and 77.0%, respectively), and mean ages at diagnosis were 69.9 and 68.1 years. From 2013 to 2023, there was an increase in the total number of patients observed in the database with a documented stage, from 7,159 to 9,115 (27.3% increase) for NSCLC and from 1,162 to 1,595 (37.3% increase) for SCLC. This was largely driven by an absolute increase in advanced stage diagnoses. The proportion of patients diagnosed with Stage IV NSCLC increased from 43.3% in 2013 to 49.3% in 2023, while the proportions of Stage 0/I and II diagnoses decreased. A similar trend was observed for SCLC, with 60.3% of patients diagnosed with Stage IV in 2013 compared to 68.2% in 2023. The proportion of Stage IV NSCLC cancers increased in the pandemic period, from 48.0% in 2019 to 51.6% in 2020 and 50.6% in 2021. Conclusions: Over the last decade, the proportion of advanced stage LC cases has increased, possibly reflecting changes in referral patterns and utilization specific to the community setting, including those related to the COVID-19 pandemic. The burden of advanced disease highlights the need for continuous investment in advanced-stage treatments as well as early detection efforts.