Evaluation of disease-free survival as a predictor of overall survival and assessment of real-world burden of disease recurrence in resected early-stage non-small cell lung cancer.

Intermediate endpoints, such as disease-free survival (DFS), have shown good correlation with overall survival (OS) in early-stage non-small cell lung cancer (NSCLC) clinical trials. However, real-world data are limited, and no previous real-world study has quantified the clinical and economic burden of disease recurrence. To examine the association between real-world DFS (rwDFS) and OS and quantify the association between NSCLC recurrence and health care resource utilization (HCRU), health care costs, and OS in patients with resected early-stage NSCLC in the United States. Data from the Surveillance, Epidemiology, and End Results-Medicare database (2007-2019) for patients with newly diagnosed stage IB (tumor size ≥ 4 cm) to IIIA (American Joint Committee on Cancer 7th edition) NSCLC who underwent surgery for primary NSCLC were analyzed in this retrospective observational study. Baseline patient demographic and clinical characteristics were described. rwDFS and OS were compared between patients with vs without recurrence using Kaplan-Meier curves and the log-rank test; their correlation was assessed using normal scores rank correlation. All-cause and NSCLC-related HCRU and health care costs were summarized, and mean monthly allcause and NSCLC-related health care costs were compared between cohorts using generalized linear models. Of the 1,761 patients who underwent surgery, 1,182 (67.1%) had disease recurrence; these patients had shorter OS from the index date and shorter subsequent OS at each postsurgery landmark (ie, 1, 3, and 5 years) than those without recurrence (all < 0.001). OS and rwDFS were significantly correlated (0.57; < 0.001). Patients with recurrence also had significantly higher all-cause and NSCLC-related HCRU and mean monthly all-cause and NSCLC-related health care costs during the study period. Postsurgery rwDFS was significantly correlated with OS in patients with early-stage NSCLC. Patients with postsurgery recurrence had a higher risk of death and incurred higher HCRU and health care costs than those without recurrence. These findings highlight the importance of preventing or delaying recurrence in patients with resected NSCLC. Dr West is Senior Medical Director at AccessHope and an Associate Professor at City of Hope. He also serves on the advisory board for Amgen, AstraZeneca, Genentech/Roche, Gilead, Merck, Mirati Therapeutics, Regeneron, Summit Therapeutics, and Takeda and as a speaker for AstraZeneca and Merck. Drs Hu, Chirovsky, and Samkari are employees of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA and own stock/stock options in Merck & Co., Inc., Rahway, NJ, USA. Drs Zhang, Song, Gao, and Signorovitch, Mr Lerner, and Ms Jiang are employees of Analysis Group, Inc., a consulting company that has provided paid consulting services to Merck Sharp & Dohme LLC., a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, which funded the development and conduct of this study and article. This study used the linked SEER-Medicare database. The interpretation and reporting of these data are the sole responsibility of the authors. The collection of cancer incidence data used in this study was supported by the California Department of Public Health pursuant to California Health and Safety Code Section 103885; Centers for Disease Control and Prevention's National Program of Cancer Registries, under cooperative agreement 5NU58DP006344; the National Cancer Institute's SEER Program under contract HHSN261201800032I awarded to the University of California, San Francisco, contract HHSN261201800015I awarded to the University of Southern California, and contract HHSN261201800009I awarded to the Public Health Institute. The ideas and opinions expressed herein are those of the authors and do not necessarily reflect the opinions of the State of California, Department of Public Health, the National Cancer Institute, and the Centers for Disease Control and Prevention or their contractors and subcontractors.