ABSTRACT
Normal tissues in the period of development are more radio-sensitive than adult normal tissues, and the relative sparing effect of low dose per fraction for late morbidity is therefore exploited using doses per fraction of 1.2-1.8 Gy. Sequential studies in various tumour types have led to reductions in total dose and target volumes. Nevertheless, radiotherapy is still an important component of curative therapy for many tumour types and remains a valuable tool for easy and effective palliation.
