title: [Dose fractionation in cancer radiotherapy].
abstract: Radiobiological research have enlarged the field of applications of radiotherapy in cancer treatment. The study of the biological effects of radiation on tumours (T) and normal tissues (NT) has showed that: 1) damage to NT is related directly with dose per fraction and inversely with the alpha/beta ratio; 2) the maximum differential effect of irradiation between T and NT is obtained when lower doses per fraction and shorter time periods are used. One exception to this rule is given by T whose alpha/beta ratio is lesser than that of NT. In these T treatment with high doses per fraction does increase tumour control and reduce late complications.
authors.forename: Vicente
authors.initials: V
authors.lastname: Pedraza Muriel
mesh_terms: D019583:Dose Fractionation, Radiation; D006801:Humans; D009369:Neoplasms / Q000532:radiotherapy*