[Intracellular recovery--basis of hyperfractionation].

The radiobiological basis of a hyperfractionated radiation therapy versus conventional fractionation with respect to therapeutic gain, i.e., improved normal tissue sparing for the same level of tumour cell inactivation, will be presented. Data on the recovery potential of various tissues as well as the kinetics of repair will be given. The problem of incomplete repair with short irradiation intervals will be discussed.