Implementation of Earlier Diagnoses and Testing May Maximize Survival Outcomes for EGFR+ NSCLC

In a large retrospective analysis of patients with non–small cell lung cancer (NSCLC), the prevalence of EGFR mutation appeared to be higher at more advanced stages and EGFR status had an impact on survival outcomes, underscoring a need to diagnose and test patients early to identify those who may benefit from treatment with an effective EGFR inhibitor, according to results from presented during the 2021 European Lung Cancer Congress (ELCC 2021).¹

In patients with stage I-III NSCLC tested for an EGFR mutation, 16% were found to be EGFR mutation–positive, the study showed.

With the influence of clinical trial research, like the ADAURA study, which showed how beneficial the use of an EGFR tyrosine kinase inhibitor can be for patients with earlier-stage EGFR-positive NSCLC, the research aimed to determine how testing patterns in the United States impact treatment outcomes. In ADAURA, adjuvant treatment with osimertinib (Tagrisso) achieved a statistically significant improvement in disease-free survival compared with placebo in patients with stage IB-IIIA EGFR-mutant NSCLC (HR, 0.20; 99.12% CI, 0.14-0.30; P < .001).^1,2

The retrospective study utilized the CancerLinQ Discovery (CLQD) database to evaluate 33,486 patients with stage I-III NSCLC who were 18 years of age or older and diagnosed between January 2014 and December 2018. Patients were followed from the time of their diagnosis until death of any cause, date of last clinical activity according to the CLQD, or until the cutoff date of September 2020. The majority of the patients included in the analysis had stage III disease (n = 14,280). Overall, 3121 patients had testing information available, including 1034 patients with stage I NSCLC, 560 with stage II disease, and 1527 with stage III disease. Of these patients, EGFR mutations were identified in 20%, 13%, and 14%, respectively. Eighty-one percent of patients were also tested for an ALK mutation, 50% for a ROS1 mutation, and 36% were tested for PD-L1 expression.

At baseline, the median age at diagnosis was 68 years (range, 60-75). The patient population was 56% female and 73% White. Most patients with available information had an ECOG performance status of 0 or 1 (42%), and 8% had an ECOG performance status of 2 or greater. Also, 86% of patients were found to have non-squamous histology, and 75% had a history of smoking.

By way of a Kaplan-Meier analysis, overall survival (OS) was defined as the time from diagnosis to death. Data were censored for patients who did not have a death event by the data cutoff date. Patients were followed for a median of 23.3 months (interquartile range, 11.2-39.7). The OS rates observed in patients with stage I NSCLC at 60 months were 72.0%, which was the highest rate among the different stages. Patients with stage II disease had a 60-month OS rate of 55.5% and those with stage III disease had an OS rate of 29.5%.

A notable finding of the analysis was that patients with EGFR-positive NSCLC appeared to have prolonged survival compared with those who tested negative for an EGFR mutation. The survival rate for stages I-III disease at 1, 2, and 5 years, respectively, in the EGFR-mutant population was 96.5%, 84.7%, and 53.7%. In comparison, patients with stage I-III EGFR-negative tumors had a survival rate of 83.2% at 1 year, 64.2% at 2 years, and 37.6% at 3 years.

In addition to early EGFR testing, the real-world results show that testing for other biomarkers like ALK mutation, PD-L1 expression, and ROS1 mutation is also important to identify patients who may derive benefit from other effective agents.

_References:

_{1. Potter D, Li J, Luo L, et al. EGFR testing patterns and survival in stage I-III non-small cell lung cancer (NSCLC): analysis using the CancerLinQ Discovery® (CLQD) database. Presented at: 2021 European Lung Cancer Virtual Congress; March 25-27, 2021; Virtual. Abstract 66P.}

_{2. Wu Y, Tsuboi M, He J, et al. Osimertinib in resected EGFR-mutated non–small-cell lung cancer. N Engl J Med. 2020;383:1711-1723. doi:10.1056/NEJMoa2027071}