Table 4.

Multivariable Logistic Regression Models for Axillary Lymph Node Dissection According to Axillary Imaging Results

	Odds Ratio	95% CI	p Value
Mammography
Age	1.02	0.99–1.04	0.18
Imaging tumor size, cm	1.50	1.14–1.97	0.0039
Total nodes removed at SLNB	1.33	1.20–1.48	<0.0001
No abnormal LNs on mammogram	1.0 (ref)
Abnormal LNs on mammogram	2.61	1.10–6.18	0.030
Ultrasound
Age	1.02	0.99–1.04	0.20
Imaging tumor size	1.57	1.19–2.07	0.0014
Total nodes removed at SLNB	1.31	1.18–1.45	<0.0001
No abnormal LNs on US	0.57	0.30–1.07	0.079*
Abnormal LNs on US	1.55	1.27–5.88	0.25*
Axillary US not done	1.0 (ref)
MRI
Age	1.01	0.99–1.04	0.29
Imaging tumor size	1.51	1.15–1.99	0.0033
Total nodes removed at SLNB	1.32	1.19–1.46	<0.0001
No abnormal LNs on MRI	0.80	0.40–1.59	0.52
Abnormal LN on MRI	1.47	0.68–3.16	0.33†
MRI not done	1.0 (ref)
Combined axillary imaging
Age	1.02	0.99–1.04	0.17
Imaging tumor size	1.56	1.18–2.07	0.0017
Total nodes removed at SLNB	1.30	1.17–1.44	<0.0001
No abnormal LNs on US or MRI	1.0 (ref)
Abnormal LNs on US or MRI	3.22	1.65–6.29	0.0006
Imaging with mammogram only	1.55	0.76–3.16	0.23‡

^*p Value for overall type 3 test is 0.0030.

^†p Value for overall type 3 test is 0.380.

^‡p Value for overall type 3 test is 0.0028.

LN, lymph node; ALND, axillary lymph node dissection; US, ultrasound.