Minimal Risks With SBRT in Stage I NSCLC

TOPLINE:

Patients with stage I non–small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT) have a low rate of acute toxicities and 90-day mortality, according to a recent study evaluating real-world patient outcomes.

METHODOLOGY:

• SBRT is generally considered a safe treatment option in patients with stage I NSCLC who have medically inoperable tumors or who refuse surgery. Although rare, clinically relevant acute toxicities or early mortality can occur.
• In the current real-world analysis, researchers explored toxicity and 90-day mortality outcomes in patients who received SBRT to develop a better understanding of how often they happen and whether certain patients are at higher risk.
• Researchers analyzed data from the Dutch Lung Cancer Audit for Radiotherapy database, which included 7279 patients with stage I NSCLC who received SBRT between January 2017 and December 2021.
• Participants had a mean age of 72.5 years; 21.6% were older than 80 years. Over half were men (50.7%), most (73.3%) had WHO scores of 0-1, and about two thirds (64.6%) had cT1a-b tumors, mostly in the upper lobes (65.2%).
• Prediction models for acute toxicity and 90-day mortality were developed and internally validated using logistic regression analysis. Acute toxicity was defined as grade 2 or higher radiation pneumonitis or grade 3 or higher non-hematologic toxicity within 90 days after SBRT. The 90-day mortality was defined as mortality from any cause within 90 days after SBRT.

TAKEAWAY:

• Acute toxicity was observed in 3.8% patients, with more common types including dyspnea (1.8%), radiation pneumonitis (1.2%), fatigue (0.3%), and dysphagia (0.2%).
• Predictors for acute toxicity included WHO performance status of 2 or higher (adjusted odds ratio [aOR], 1.89; P = .003), middle or lower lobe tumor location (aOR, 1.38), cT1c-cT2a stage (aOR, 1.66), as well as lower forced expiratory volume in 1 second and higher mean lung dose.
• Overall, 90-day mortality was observed in 1.7% patients, with predictors including male sex, WHO performance status of 2 or higher (aOR, 6.11; P < .001), and acute toxicity (aOR, 8.89; P < .001).
• Advanced age was not associated with a higher risk for acute toxicity or 90-day mortality.

IN PRACTICE:

“This real-world study confirms that clinically relevant acute toxicity after lung SBRT for stage I NSCLC is rare,” and the 90-day mortality rate is low, the authors wrote. “Although these findings could inform clinical practice and enable individualized risk estimations, these parameters (and the others in the presented nomograms) should not serve as contraindication for SBRT as the benefits in terms of local control and survival outweigh the risks in most patients.”

SOURCE:

This study, led by Peter S.N. van Rossum, MD, PhD, Amsterdam UMC in Amsterdam, the Netherlands, was published online in Journal of Thoracic Oncology.

LIMITATIONS:

Patients with ultracentral tumor locations were excluded, which may have limited the generalizability of the findings. The Dutch Lung Cancer Audit for Radiotherapy database does not register whether a patient has interstitial lung disease or whether the treated tumor is at a central location, which carry increased risks for toxicity. The findings may not be applicable to patients receiving combined immunotherapy and SBRT, as this combination was not included in the current analysis. External validation of the prediction models is needed for application outside the Netherlands.

DISCLOSURES:

van Rossum disclosed receiving grants from various organizations. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.