Future Analyses of SBRT and CRT for Stage I Non-Small Cell Lung Cancer Will ‘Hopefully’ Guide Providers on How to Avoid Excessive Toxicity, Says Expert

Future investigations of stereotactic body radiation therapy (SBRT) compared with conventional hypofractionated radiotherapy (CRT) in patients with stage I inoperable non-small cell lung cancer should focus on several factors including quality of life, according to an expert.

During the 2022 American Society for Radiation Oncology (ASTRO) Annual Meeting, CancerNetwork^® spoke with Anand Swaminath, MD, about future analyses planned for the phase 3 LUSTRE trial (NCT01968941).

According to Swaminath, an associate professor, clinician scientist, and radiation oncologist at Juravinski Cancer Centre in Ontario, Canada, the goal is to give providers a guide on how to better limit toxicity in patients.

Transcript:

Because I mentioned previously that the trial closed early, we weren't able to meet our accrual target. Because the trial is underpowered to show that difference in control rates, I think it behooves us to pool our data. We are planning on pooling our data with 2 other [radiation] trials from Australia and from Scandinavia to try to increase our statistical power, and perhaps then provide the community with robust level 1 evidence that stereotactic radiation should be considered in these patients.

The second thing is that we're going to be looking at the central tumors, because we noted a preponderance of increased toxicity in the central group. We wanted to ensure that it was still safe to treat both central and another moniker now that's going around called ultracentral. These are tumors that are within that bronchial tree, but the tumor itself is either overlapping or touching the bronchial tree. Those may even be higher risk than just having a tumor that's nearby. We have several patients on our trial who met the definition of ultracentral lung cancer. We're going to be looking at those specifically to see what the metrics and what the parameters are that would lead to possibly increasing toxicity in that group. Hopefully, that will provide the community a great reference for them, so when they start treating these patients with stereotactic radiation, they will have guidance to know how to avoid creating excessive toxicity in those patients.

The final thing that we're going to do is we're going to be looking at our secondary outcomes. Our secondary outcomes include quality of life; cost-effectiveness; and patterns of failure, so how did these patients progress and what treatments did they get following their [disease] progression?

Reference

Swaminath A, Parpia S, Wierzbicki M, et al. LUSTRE: a phase III randomized trial of stereotactic body radiotherapy (SBRT) vs. conventionally hypo fractionated radiotherapy (CRT) for medically inoperable stage I non-small cell lung cancer (NSCLC). Presented at 2022 American Society for Radiation Oncology Annual Meeting (ASTRO); October 23-26, 2022; San Antonio, TX. Abstract LBA 08. Accessed November 4, 2022.