Results from an international clinical trial show that a 14-gene molecular assay can help identify patients with early-stage non-squamous non-small cell lung cancer (NSCLC) who could benefit from adjuvant chemotherapy after surgery.

The research was presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place May 30-June 3 in Chicago.

“This is the first large prospective randomized trial to demonstrate that a 14-gene molecular assay can identify who could benefit from adjuvant chemotherapy among a high-risk group of patients with stage IA-IIA non-squamous non-small cell lung cancer who otherwise may not typically receive such therapy,” said lead study author David Spigel, MD, FASCO, Sarah Cannon Research Institute in Nashville, Tennessee.

This study enrolled 421 patients with stage IA-IIA non-squamous NSCLC who had surgery to remove their tumour(s). Those tumours were tested and categorized as low, intermediate, or high risk via a 14-gene assay called the RiskReveal assay.

At the time of this interim analysis, there were 194 intermediate-and high-risk patients who could be evaluated. Patients who were categorized as intermediate or high risk were randomized to four cycles of platinum-based adjuvant chemotherapy (87 patients) or to observation (107 patients).

Researchers then compared the time to disease recurrence in each group. About 55% of each group had IA NSCLC, and demographics between the two groups were similar.

Key Findings

• After 24 months, patients who received adjuvant chemotherapy had a 78% lower risk of cancer recurrence compared to the observation group.
• In the adjuvant chemotherapy group, 96% of patients did not have a cancer recurrence. In the observation group, 79% of patients did not have a cancer recurrence.
• The trial’s median disease-free survival endpoint was not reached in either group, meaning more than half of patients would not have experienced disease recurrence in either group.
• At the time of the interim analysis, the Data Safety Monitoring Board recommended that the clinical trial stop enrolling new patients because of how successful the assay was at determining which of these patients could benefit from adjuvant chemotherapy. Follow-up continues with those who were already enrolled.

Researchers will continue to follow the patients already enrolled in this study and will look at how advances in targeted therapy and immunotherapy could be applied to earlier stages of NSCLC.

"These early, interim results from a promising prospective, randomized study evaluating the role of adjuvant chemotherapy in patients with stage IA-IIA non-small cell lung cancer identified as high-risk by a 14-gene molecular assay pave the way for more precise, biomarker-driven therapy decisions,” said Charu Aggarwal, MD, MPH, FASCO, Leslye M Heisler Professor of Lung Cancer Excellence at University of Pennsylvania – Abramson Cancer Center, and an ASCO Expert in lung cancer.

Source: ASCO