文档介绍：乳腺癌低分次大分割放射治疗
Hypofractionated Radiation Therapy for Breast Cancer
研究背景
技术路线
临床优势及问题
Women receiving radiation therapy following breast conserving surgery had a 19% reduction in 5-year local recurrence (7 vs. 26%) which translated into a % reduction in 15-year over all mortality ( %).
Clarke M, Collins R, Darby S, et al. Effects of radiotherapy and of differences in the extent of surgery for early breast cancer on local recurrence and 15-yearsurvival: an overview of the randomised trials. Lancet 2005; 36 6 :2087–2106.
receiving postmastectomy radiation had a 17% reduction in 5-year local re- currence ( vs. %) which translated into a % reduction in15-year overall mortality (. %)
Clarke M, Collins R, Darby S, et al. Effects of radiotherapy and of differences in the extent of surgery for early breast cancer on local recurrence and 15-yearsurvival: an overview of the randomised trials. Lancet 2005; 36 6 :2087–2106.
乳腺癌放射治疗的新趋势：精，小，快
精：精确确定放射治疗在综合治疗中的作用
p T1,2 N :1-3 个 ?
小：放射治疗的范围缩小，保乳术后放疗时部分乳腺照射受到重视（APBI）
快：低分次大分割放射治疗（Hypofractionation的应用）
体外试验测得乳腺癌细胞的α/β值大约为4
MatthewsJ,MeekerB, of human tumor cell lines in vitro to fractionated irradiation. International Journal of Radiation Oncology Biology and Physics 1989;16:133e8.
SteelG,DeaconJ, dose-rate effect in human tumour and Oncology 1987;9:299e310.
Castro JR 将放射生物学应用于临床回顾性资料，最早得出大分割治疗是安全有效的模式。
Douglas BG, Castro JR. Novel fractionation schemes and high linear energy transfer. Prog Exp Tumor Res. 1984;28:152–165.
国外临床试验
Yarnold1986-1998 1410 T1-3N0-1
START A 1998-2002 2236 T1-3N0-1
START B 1999-2001 2215 T1-3N0-1
研究目的：大分割治疗的疗效和安全性
Whelan1993-1996 1234 T1-2N0
研究设计