EBRO 2017

Margins for PTV

• Ideally, measure random and systematic error • calculate margins so that ≥99 % of CTV receives ≥95 % of prescribed dose

Adjustment of the PTV is not permitted 1C Dose prescription and reporting follow ICRU standards 1B

“Old-fashion” RT “High-precision” RT Blocks = GTV + 2 cm CTV = GTV + 5-8 mm

PTV = CTV + mobility + planning + setup Blocks = PTV + PENUMBRA