10/09/2026
Results from the Phase III Alliance trial (A071801) presented today at the American Society for Radiation Oncology as a late-breaking abstract in the ASTRO plenary session offer evidence that could improve post-operative care for patients with large brain metastases.
🔍 The Clinical Challenge
Surgical resection is often necessary for large brain metastases to relieve pressure and manage neurological symptoms. However, microscopic cancer cells left behind in the surgical cavity pose a high risk of local recurrence. While stereotactic radiosurgery (SRS) is preferred over whole-brain radiation to preserve cognitive function, delivering a single large dose after surgery can risk toxicity to healthy surrounding brain tissue.
📊 Key Trial Findings
Enrolling 242 patients across multiple centers, researchers evaluated single-session SRS against fractionated stereotactic radiosurgery (delivered in 3 to 5 sessions):
• Higher Local Control: 1 year post-treatment, 87% of patients in the fractionated group were free from recurrence at the surgical site, compared to 81% in the single-session group.
• Survival Benefit: Median overall survival reached 29 months with fractionated radiosurgery vs. 20 months with a single session.
• Safety Profile: Adverse event rates were low and showed no significant difference between treatment arms.
💡 Why It Matters
As Dr. Paul D. Brown (Mayo Clinic) and Dr. Ayal A. Aizer (Dana-Farber Brigham Cancer Center) noted, dividing radiation over several treatments gives healthy brain tissue time to recover while ensuring an effective therapeutic dose is delivered.
This important Phase III trial transitions fractionated stereotactic radiosurgery from a practice supported primarily by retrospective data to a high-evidence standard of care for larger surgical cavities.
Congratulations to the Alliance for Clinical Trials in Oncology and all participating investigators on this important study!
🔗 Read the full release: https://bit.ly/ASTRO26
