2017_SBRT_Course Book

Learning Objectives

▪ To give an overview of margin concepts ▪ Why do we use or need margins?

▪ To provide a qualitative understanding of a margin recipe ▪ To provide an overview of assumptions being made in the derivations of the van Herk margin recipe ▪ To discuss applicability of “conventional” margin concepts in hypo-fractionated / single fraction SBRT ▪ To discuss the effect of a limited number of fractions on random error ▪ Explain why a random error for hypofractionated treatments results in a systematic error ▪ Explain how to calculate margins for single fraction and hypofractionated treatment and provide some practical examples ▪ How to add errors?

▪ To discuss margins for tumors that move with respiration

▪ To give suggestions for further reading