Renal atrophy following gated delivery of stereotactic ablative radiotherapy to adrenal metastases

Abstract

Stereotactic ablative radiotherapy (SABR) planning for adrenal metastases aims to minimize doses to the adjacent kidney. Renal dose constraints for SABR delivery are not well defined. In 20 patients who underwent MRguided breath-hold SABR in five daily fractions of 8-10 Gy, ipsilateral renal volumes receiving ≥20 Gy best correlated with loss of renal volumes, with median renal volume reduction being 6% (range: 3%-11%, 10th-90th percentiles). Organ function did not deteriorate in 18 patients, who had post treatment renal function tests available. This suggests that the ipsilateral renal volume receiving 20 Gy can be used as partial organ dose constraint for SABR to targets in the upper abdomen.

Factors influencing local control after MR-guided stereotactic body radiotherapy (MRgSBRT) for adrenal metastases

“…MR-guided SBRT (MRgSBRT), with its ability to better visualize soft tissue and track tumors during treatment, has been shown to be a novel but reproducible and accurate treatment modality that may reduce treatment volumes and may consequently minimize toxicity [10] . Early single-institution clinical outomes of adrenal SBRT with MRgRT have also been published [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] . The main aim of this multi-institutional pooled analysis was to report the clinical outcomes and toxicities after adrenal MRgSBRT on a 0.35 T MR-linac.…”