ESTRO 2021 Abstract Book

S1146

ESTRO 2021

Results With a median follow-up of 8 months (2-20) all patients are alive; 1p (2.5%) developed biochemical progression; no distant relapses were observed. Acute toxicity: genitourinary G1 10p (25%) and G2 4p (10%); gastrointestinal G1 10p (25%). Late toxicity (in 28p with follow-up >90 days) was G1 genitourinary and gastrointestinal in 1p each (2.5%). Conclusion Ultra-hypofractionated adjuvant/salvage SBRTs eems to be a feasible and safe option after radical prostatectomy. Longer follow-up is necessary to confirm observed results.

PO-1396 CBCT-guided online adaptive radiotherapy: results of the first fifty prostate cancer patients L. Zwart 1 , L. ten Asbroek 1 , E. van Dieren 1 , S. Koch 1 , F. Ong 1 , A. Bhawanie 1 , E. de Wit 1 , J. Dasselaar 1