Biomarker Testing “Essential” to Ensure Appropriate Treatment in NSCLC

An uptick in biomarker testing for non-small cell lung cancer (NSCLC) over the past decade indicates an ongoing trend toward personalization of treatment choices.

“The treatment for [non-small cell lung cancer (NSCLC)] is becoming increasingly biomarker driven, with targeted therapies requiring testing using companion molecular diagnostics,” Ernest Lo, MD, and colleagues wrote. “However, little is known about how biomarker tests are conducted and used to guide treatments in patients with [early NSCLC] in the real-world setting.”

For a study published in Oncology and Therapy, Dr. Lo and colleagues examined use of biomarker testing and subsequent treatment among patients with early NSCLC in the real-world setting. The retrospective observational cohort study used an EHR-derived oncology database to enroll adult patients with early NSCLC diagnosed between January 2011 and December 2021. The researchers examined rates of biomarker testing within 6 months of diagnosis and treatment received among patients who underwent the five most common biomarker tests.

Time From Biomarker Testing to Treatment Initiation

The study included 1,031 patients, most of whom were White (91.8%) and had a history of tobacco use (81.4%). Most patients were aged 65 and older (65-74: 39.4%; 75-84: 26.4%; ≥85: 5.1%).

Most patients (74.1%) underwent one or more biomarker tests within 6 months of early NSCLC diagnosis. Dr. Lo and colleagues reported that the proportion of patients receiving biomarker testing increased from 55.3% in 2011 to 88.1% in 2021. “In particular, there was a significant increase in the proportion of patients who received PD-L1 testing after the index diagnosis year of 2016,” they wrote.

The five most tested biomarkers were EGFR (64%), ALK (60%), PD-L1 (48%), ROS1 (46%), and BRAF (40%). Almost all of the 763 patients who had the five most common biomarker tests performed did so before the start of systemic therapy, according to the study results.

The average time between early NSCLC diagnosis and biomarker testing ranged from 5.3 days for PD-L1 to 8.7 days for BRAF. The time between biomarker testing and start of systemic therapy varied with both biomarker and treatment type, ranging from 49 to 56 days on average for chemotherapy and from 94 to 113 days for treatments other than chemotherapy.

Biomarker Testing in NSCLC Increased Over Past Decade

Dr. Lo and colleagues wrote that, to their knowledge, this study is the first real-world assessment of biomarker testing use and subsequent therapy among patients with early NSCLC. The results showed a high rate of biomarker testing in US patients with early NSCLC, with tests for certain biomarkers increasing over time in the past decade. This indicates “a continuous trend toward the personalization of treatment decisions,” they note.

“Timely biomarker testing is essential for patients with NSCLC to ensure that patients receive the appropriate treatment at the right time,” Dr. Lo and colleagues wrote. “With the rapidly evolving treatment landscape and testing recommendations for [early NSCLC], future research is needed to understand whether biomarker testing has improved optimal treatment decision making and long-term survival outcomes for patients with [early NSCLC].”