Table 2.

Risk variables for regional lymph nodes metastasis determined by univariate and multivariate logistic regression analyses

Characteristics	Univariate analysis			Multivariate analysis
	OR	P value	95% CI	OR	P value	95% CI
Age (years)
≤ 60	Reference			Reference
> 60	0.82	0.096	0.65–1.04	0.85	0.199	0.66–1.09
Race
White	Reference			Reference
Black	1.16	0.335	0.86–1.57	0.98	0.883	0.71–1.35
Othersa	1.25	0.325	0.80–1.95	1.12	0.639	0.70–1.78
Marital status
Unmarried	Reference			Reference
Married	0.73	0.010	0.58–0.93	0.80	0.089	0.62–1.03
Unknown	0.83	0.560	0.43–1.58	0.95	0.875	0.48–1.87
Grade
I	Reference			Reference
II	2.07	0.119	0.83–5.16	1.83	0.208	0.71–4.68
III	3.65	0.003	1.56–8.54	2.69	0.026	1.12–6.46
IV	4.36	0.003	1.63–11.63	3.05	0.031	1.10–8.45
Laterality
Right	Reference			Reference
Left	0.82	0.094	0.65–1.04	0.79	0.058	0.62–1.01
ER status
Negative	Reference			Reference
Positive	1.49	0.007	1.12–1.98	1.60	0.006	1.14–2.23
PR status
Negative	Reference			Reference
Positive	1.08	0.644	0.77–1.52	0.97	0.870	0.65–1.44
Tumor size
≤ 2 cm	Reference			Reference
> 2 cm and ≤ 5 cm	2.39	< 0.001	1.68–3.39	2.19	< 0.001	1.54–3.13
> 5 cm	6.10	< 0.001	4.18–8.91	5.51	< 0.001	3.74–8.11

OR Odds ratios, CI Confidential interval, ER Estrogen receptor, PR progesterone receptor

^aIncludes: American Indian, native Alaskan and Asian, Pacific Islander