Preinv-4	Radiotherapy
Grade of recommendation A	a. Postoperative radiotherapy after breast-conserving surgery for DCIS lowers the rate of invasive and non-invasive local recurrences without any demonstrable effect on overall survival.
Level of evidence 1a	(Bijker N et al. 2006; Clarke M et al. 2005; Cochrane: Goodwin A et al. 2009; Cutuli B et al. 2002; Cuzick J et al. 2011; EBCTCG: Correa C et al. 2010; Emdin SO et al. 2006; Holmberg L et al. 2008)
Grade of recommendation A	b. The absolute risk reduction in the local recurrence rate by radiotherapy after breast-conserving surgery for DCIS depends on individual factors.
Level of evidence 1b	(Baxter NN et al. 2005; Boyages J et al. 1999; Cochrane: Goodwin A et al. 2009; Cuzick J et al. 2011; EBCTCG: Correa C et al. 2010; Houghton J et al. 2003; Omlin A et al. 2006; Shelley W et al. 2006; Smith BD et al. 2006)