Multicenter phase 2 trial of stereotactic ablative body radiotherapy for primary renal cell carcinoma

Stereotactic ablative body radiotherapy (SABR) as a novel option for patients with primary renal cell carcinoma (RCC) who do not undergo surgical resection. The phase 2 FASTRACK II trial, at seven centers in Australia and one center in The Netherlands, evaluated SABR for RCC. The median age of the patients was 77 years (IQR 70-82). The median tumor size was 4.6 cm (IQR 3.7-5.5). All patients enrolled had T1-T2a and N0-N1 disease. Local control at 12 months from start of treatment was 100%. Grade 3 treatment-related adverse events were seen in 10% of patients; there were no grade 4 or 5 TRAEs. The authors conclude that among patients with RCC who are not eligible for or refuse surgical resection, SABR was an effective treatment strategy with no observed local failures or cancer-related deaths, and an acceptable side-effect profile and renal function after SABR.