Table 2.

Multivariable analysis of all invasive breast cancer patients (n = 36,050) diagnosed in 2011-2013 per defined outcome modality

Outcome characteristic	MRI use			Primary mastectomy			Margin involvement (more than focal)			Secondary mastectomy			Contralateral breast cancer
	OR	95% CI	P	OR	95% CI	P	OR	95% CI	P	OR	95% CI	P	OR	95% CI	P
MRI
No	N/A			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
Yes				1.22	1.15–1.29	<0001	0.84	0.73–0.97	0.015	1.07	0.89–1.29	0.434	3.55	3.01–4.17	<.0001
Year of incidence
2011	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
2012	1.02	0.96–1.09	0.468	0.94	0.88–0.99	0.025	0.84	0.73–0.96	0.011	0.79	0.65–0.95	0.012	1.05	0.87–1.26	0.636
2013	1.11	1.04–1.18	0.001	0.93	0.88–0.99	0.020	0.73	0.63–0.84	<.0001	0.80	0.66–0.97	0.026	1.18	0.98–1.41	0.081
Age group (years)
70+	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
<50	6.38	5.89–6.91	<.0001	0.65	0.60–0.70	<.0001	1.33	1.11–1.60	0.002	1.99	1.56–2.54	<.0001	0.56	0.44–0.71	<.0001
50–69	2.84	2.65–3.04	<.0001	0.46	0.44–0.49	<.0001	0.86	0.74–0.99	0.041	1.02	0.83–1.26	0.848	0.65	0.54–0.77	<.0001
Histology
Ductal	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
Lobular	3.48	3.25–3.73	<.0001	1.55	1.45–1.67	<.0001	1.94	1.64–2.28	<.0001	2.55	2.06–3.14	<.0001	1.15	0.94–1.39	0.168
Other	0.88	0.78–0.99	0.026	1.01	0.90–1.12	0.920	1.41	1.11–1.80	0.005	1.12	0.79–1.59	0.529	0.95	0.69–1.31	0.754
Clinical tumor size (cT)
cT1	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
cT2	1.66	1.57–1.76	<.0001	3.17	3.00–3.35	<.0001	1.49	1.29–1.71	<.0001	1.40	1.17–1.69	<.0001	0.57	0.46–0.70	<.0001
cT3–4	2.82	2.44–3.25	<.0001	34.67	26.08–46.09	<.0001	3.21	1.55–6.66	0.002	2.19	0.78–6.16	0.139	0.51	0.30–0.89	0.017
Unknown	0.66	0.57–0.75	<.0001	2.34	2.09–2.62	<.0001	2.42	1.91–3.07	<.0001	2.63	1.93–3.59	<.0001	2.23	1.72–2.88	<.0001
Clinical nodal status (cN)
cN0	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
cN1–3	0.94	0.87–1.02	0.131	2.53	2.33–2.75	<.0001	1.50	1.21–1.84	0.0001	1.50	1.14–1.98	0.004	0.81	0.59–1.11	0.189
Unknown	1.00	0.78–1.28	0.984	1.42	1.13–1.79	0.003	1.60	0.98–2.64	0.063	1.86	0.97–3.54	0.061	0.82	0.40–1.70	0.599
ER, PR and HER2 status
ER+ or PR+, and HER2−	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
ER+ or PR+, and HER2+	1.03	0.93–1.13	0.595	1.17	1.07–1.29	0.001	1.30	1.05–1.59	0.014	1.31	1.00–1.74	0.055	0.97	0.69–1.36	0.853
ER− and PR− and HER2−	0.90	0.82–0.99	0.023	1.08	0.99–1.18	0.095	0.71	0.56–0.90	0.004	1.15	0.86–1.54	0.356	0.81	0.55–1.20	0.291
ER− and PR− and HER2+	1.11	0.97–1.27	0.148	1.56	1.36–1.79	<.0001	1.20	0.86–1.66	0.279	1.95	1.30–2.93	0.001	0.56	0.27 –1.14	0.110
Unknown	0.71	0.60–0.85	0.0001	1.18	1.03–1.36	0.021	0.86	0.61–1.22	0.398	1.41	0.91–2.18	0.122	2.33	1.72–3.14	<.0001
Tumor grade
1	1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
2	0.91	0.86–0.97	0.005	1.23	1.15–1.31	<.0001	1.48	1.26–1.73	<.0001	1.59	1.27–1.99	<.0001	0.71	0.60–0.84	<.0001
3	0.79	0.73–0.85	<.0001	1.18	1.09–1.28	<.0001	1.63	1.35–1.97	<.0001	1.87	1.44–2.43	<.0001	0.35	0.26–0.47	<.0001
Unknown	1.06	0.92–1.22	0.409	1.30	1.13–1.48	<.0001	1.98	1.48–2.65	<.0001	1.41	0.93–2.14	0.110	0.86	0.62–1.19	0.354
Multifocality
No	1 (ref)			1 (Ref)			1 (Ref)			1 (Ref)			1 (Ref)
Yes	2.35	2.20–2.50	<.0001	4.44	4.15–4.76	<.0001	2.85	2.44–3.34	<.0001	4.78	3.92–5.82	<.0001	1.02	0.84–1.25	0.831
Unknown	0.39	0.27–0.55	<.0001	1.48	1.16–1.90	0.002	3.46	1.63–7.35	0.001	3.89	1.42–10.6	0.008	0.87	0.45–1.71	0.688
Margin involvement
No										1 (Ref)
Yes	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	41.94	35.68–49.30	<0.001	N/A	N/A	N/A