title: [Alpha/beta ratio revisited in the era of hypofractionation].
abstract: Large doses per fraction are not recommended in daily radiotherapy due to a higher risk of late normal tissue injury. The technical refinements of modern radiotherapy and suggestions that some tumors could be sensitive to dose per fraction have renewed the interest in hypofractionated schedules. The estimation of α/β ratio value requires large samples of carefully evaluated patients in whom total and fractional doses have varied independently. Tumor repopulation has to be considered when the treatment duration is altered. Without setting aside conflicting publication, the α/β ratio values for prostate and breast (after lumpectomy) cancers could be as low as 2.5 Gy and 4 Gy, respectively. While it is too early to change our routine protocols, the time has come to conduct clinical trials comparing different fractionation schedules.
authors: Service de cancérologie-radiothérapie, hôpital Saint-Louis, AP-HP, 1, avenue Claude-Vellefeaux, 75475 Paris, France; Université Paris Diderot Paris VII, 75475 Paris, France. Electronic address: christophe.hennequin@sls.aphp.fr.
authors: C
authors: C
authors: Hennequin
authors: B
authors: B
authors: Dubray
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000532:radiotherapy*; D011836:Radiation Tolerance
keywords: Alpha-beta ratio; Breast cancer; Cancer de prostate; Cancer du sein; Dose par fraction; Dose per fraction; Prostate cancer; Radiotherapy; Radiothérapie; Rapport α/β