Table 3. Stratification analysis of tumor recurrence rates in patients with HR+ DCIS after mastectomy.

Characteristic	ET (N=791)	Non-ET (N=216)	HR (95% CI)	p-Value
Total	19 (791)	4 (216)	1.30 (0.48–3.52)	0.64
Age
≤50	12 (448)	1 (110)	2.91 (0.74–11.47)	0.28
>50	7 (343)	3 (106)	0.75 (0.18–3.17)	0.67
Tumor size
≤20 mm	6 (459)	2 (127)	0.82 (0.15–4.44)	0.81
>20 mm	13 (332)	2 (89)	1.75 (0.51–6.04)	0.45
Microinvasive
Yes	8 (128)	0 (29)	3.48 (0.60–20.02)	0.16
No	11 (663)	4 (187)	0.76 (0.22–2.59)	0.64
Tumor grade
I-II	10 (565)	0 (164)	3.64 (0.82–16.06)	0.09
III	9 (226)	4 (52)	0.51 (0.13–2.07)	0.26
ER
1–10%	4 (165)	2 (40)	0.47 (0.08–2.67)	0.386
>10%	15 (626)	2 (176)	2.14 (0.48–9.43)	0.305
Ki67
≥15%	7 (279)	1 (62)	0.88 (0.09–8.29)	0.67
＜15%	12 (512)	3 (154)	1.42 (0.46–4.38)	0.74
Multifocal
Yes	3 (64)	0 (13)	3.34 (0.17–67.46)	0.43
No	16 (727)	4 (203)	1.11 (0.38–3.22)	0.85
Surgery
Unilateral mastectomy	19 (776)	4 (215)	1.32 (0.45–3.93)	0.61
Bilateral mastectomy	0 (15)	0 (1)	–	–

Notes: HR, hormone receptor; DCIS, ductal carcinoma in situ; ET, endocrine therapy.

Source files available in Table 3—source data 1.