Table 3.

Development of ipsilateral invasive cancer, DCIS grade, patient age and cumulative risk at 5, 8 and 10 years (life table analysis method).

Grade of DCIS	All cases	Ipsilateral invasion Median age (range) (years)	No ipsilateral invasion	p-value for comparison of ages	5-year risk (95% CI)	8-year risk	10-year risk (95% CI)
	Median age (range) (years)		Median age (range) (years)	(ipsilateral invasion v no ipsilateral invasion)a		(95% CI)
High	63	56	64	0.005	0.23 (0.15–0.34	0.31 (0.22–0.45)	0.36 (0.24–0.50)
(n=123)	(49–86)	(49–71)	(49–86)
Intermediate	62	59	63	0.29	0.13 (0.07–0.23	0.34 (0.21–0.51)	0.39 (0.24–0.58)
(n=105)	(48–90)	(48–84)	(50–90)
Low	61	65	60	0.61	0.09 (0.04–0.21	0.09 (0.04–0.21)	0.09 (0.04–0.21)
(n=76)	(47–84)	(50–77)	(47–84)
Intermediate & low	62	60	62	0.63	0.11 (0.07–0.18)	0.25 (0.16–0.37)	0.28 (0.18–0.43)
(n=181)	(47–90)	(48–84)	(47–90)
All gradesb	62	59	63	0.02	0.16 (0.12–0.22)	0.27 (0.20–0.35)	0.31 (0.23–0.40)
(n=311)	(47–90)	(48–84)	(47–90)

^aMann-Whitney U test.

^bIncludes 7 women with unknown grade.