Walter Vásquez Rivas, Radiation Oncologist, Clinical Lead MR-Linac at Quironsalud shared a post on LinkedIn:
“Adrenal SBRT on MR-Linac: Adaptive Precision in Motion.
Stereotactic body radiotherapy (SBRT) for adrenal metastases represents a high-complexity clinical scenario. We are dealing with small target volumes, close proximity to critical organs (kidney, stomach, bowel, spinal cord), and significant respiratory motion.
Achieving ablative doses while maintaining strict organ-at-risk constraints requires more than conventional image guidance.
The integration of MR-guided radiotherapy with systems such as the Unity platform by Elekta is reshaping the technical standard in this setting.
1. Daily high-resolution soft tissue visualization.
Online MRI allows direct visualization of the adrenal lesion and surrounding organs at each fraction. This reduces geometric uncertainty and supports confident target delineation based on the anatomy of the day.
2. Online adaptive workflow (ATP / ATS).
In adrenal SBRT, millimetric anatomical shifts can significantly impact dose distribution. Online adaptation enables plan re-optimization in real time, preserving PTV coverage while respecting dose constraints to adjacent organs.
3. Real-time motion management.
Continuous MR imaging enables gating strategies that reduce internal margins. This is particularly relevant in adrenal lesions, where respiratory motion can be clinically meaningful.
4. Safe biological intensification.
MR-guided SBRT facilitates the delivery of ablative regimens (e.g., 30–40 Gy in 5 fractions) with high conformality, supporting local control strategies in oligometastatic disease.
Beyond technology, this represents a shift toward biologically driven, anatomy-adaptive radiotherapy. For carefully selected patients, MR-guided adrenal SBRT offers a robust balance between efficacy and toxicity – and expands what is technically feasible in daily clinical practice.”
Other articles about SBRT on OncoDaily.