Cesium-131 Tile Radiation Tied to Longer Time to Recurrence

TOPLINEPatients with newly diagnosed brain metastases who received cesium-131 tile-based radiation therapy (TBRT) during surgical resection experienced significantly longer time to surgical bed recurrence compared to those who received standard postoperative stereotactic radiation therapy (SRT). Surgical bed recurrence-free survival was also significantly improved with TBRT, with median not reached vs 10.9 months with SRT.METHODOLOGYResearchers conducted a randomized controlled trial — open-label and non-inferiority — phase 3 trial across 32 United States centers from April 2021 through August 2025.A total of 230 patients with one surgical brain metastasis (2.0–7.0 cm) and 0–5 additional brain metastases (≤4.0 cm) were randomly assigned 1:1 to resection with TBRT (R+TBRT) or resection with SRT (R+SRT).The modified intent-to-treat population included 204 patients (103 R+TBRT, 101 R+SRT) who underwent surgery, had pathologic confirmation of brain metastasis, and had follow-up information.Co-primary outcomes were time to surgical bed recurrence and surgical bed recurrence-free survival, analyzed using Cox proportional hazards models with stratification factors as covariates.Median follow-up was 12.9 months (13.3 months for R+TBRT, 12.3 months for R+SRT).TAKEAWAYMedian time to surgical bed recurrence was not reached in R+TBRT vs 17.4 months in R+SRT (hazard ratio [HR], 0.06; P = .0070).At 12 months, the cumulative incidence of surgical bed recurrence was 1.3% in R+TBRT vs 15.4% in R+SRT (subdistribution HR, 0.07; P = .012).Median surgical bed recurrence-free survival was not reached in R+TBRT vs 10.9 months in R+SRT (HR, 0.48; P = .0021).Median overall survival (OS) was 42.5 months in R+TBRT vs 17.6 months in R+SRT (HR, 0.59; P = .032).IN PRACTICE"In this multicenter randomized phase 3 trial with the median follow-up exceeding prior practice-changing studies, TBRT was superior to contemporary postoperative SRT for both surgical bed 369 control and [surgical bed recurrence-free survival]. The reduction in SBR was substantial, and improved efficacy was achieved 370 without an increase in RN, neurocognitive decline, or deterioration in quality-of-life," wrote the authors of the study.SOURCEThe study was led by Jeffrey S. Weinberg, MD, The University of Texas MD Anderson Cancer Center in Houston. It was published online on September 28 in Journal of Clinical Oncology.LIMITATIONSThe study was open-label, though conducting a blinded trial in this context is infeasible for ethical and practical reasons. The study was not designed to gather granular data on systemic therapy such as initiation, pausing, and resumption, limiting the ability to investigate the relationship between specific agents, therapy interruptions, and observed outcomes.DISCLOSURESThe study was funded by GT Medical Technologies, Inc. Multiple authors are employees and shareholders of GT Medical Technologies, and several others reported consulting fees, honoraria, research support, or paid roles on advisory boards from various pharmaceutical and medical device companies. Additional author disclosures are reported 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.