The RESECT study: Factors associated with overall survival (OS) and relapse-free survival (RFS) among patients with stages I–III resected NSCLC without known EGFR mutations.

Abstract

8541 Background: Approximately one-third of patients with Stages I–III resected non-small-cell lung cancer (NSCLC) do not survive 5 years from diagnosis. This retrospective observational study analyzed factors associated with OS and real-world (rw) RFS among Stage I–III NSCLC patients before the introduction of immuno-oncology (IO) treatment. Methods: We analyzed data from the US CancerLinQ database for adult patients with no known EGFR mutations and no other cancers, who were diagnosed with Stage I–III NSCLC from 2014–2019 and had surgical resection within 140 days after initial diagnosis. 3081 patients met the study criteria of whom 1677 were Stage I, 853 were Stage II, and 551 were Stage III; 4 Stage I patients who received neoadjuvant or perioperative treatment were excluded (too few for analysis). Most patients received surgery only (71.5%); the rest also received adjuvant (24.7%), neoadjuvant (2.4%) or perioperative (1.5%) treatment, most often chemotherapy ± radiotherapy. Key demographics, clinical characteristics, treatment patterns, and relevant 2-way interactions were considered for inclusion in the model, based on Cox regression analyses and medical insights. Multivariable Cox regression analysis (backwards selection, p<0.05) was used to model OS and rwRFS. Results: In the multivariable analyses (in which no Stage I patients with neoadjuvant or perioperative treatment were included), factors associated with both OS and rwRFS (p<0.05) were disease stage, race, ethnicity, year of diagnosis, ECOG performance status, and neoadjuvant treatment. Factors associated with OS (p<0.05), but not rwRFS, were age, sex, time from diagnosis to surgery, and type of surgery. Factors associated with rwRFS (p<0.05), but not OS, were geographic region, nodal status, and adjuvant treatment in Stage II and III patients but not Stage I patients. Conclusions: This study identified several risk factors associated with OS and rwRFS, many of which are known. Notably, in this analysis, neoadjuvant treatment was associated with both improved OS and rwRFS in Stage II–III patients and was not evaluable in Stage I patients. However, adjuvant treatment was only associated with improved rwRFS, and only in Stage II–III patients. Based on these findings, there remains an unmet need for Stage I–III NSCLC patients. The recent introduction of IO treatment in this setting may help improve patient outcomes.