Table 2.

Adjusted^* Logistic Regression Model of Factors Associated with having Secondary Breast Cancer compared with Primary Breast Cancer

Characteristics	Odds ratios
Race/ethnicity
Non-Hispanic White	Reference
Non-Hispanic Black	1.35 (1.11, 1.66)
Hispanic	1.05 (0.91, 1.21)
Asian/Pacific Islander	0.76 (0.63, 0.92)
Age (years)
12–24	Reference
25–29	0.62 (0.23, 1.67)
30–34	0.79 (0.32, 1.98)
35–39	1.23 (0.50, 3.01)
40–44	0.96 (0.39, 2.34)
45–50	0.42 (0.17, 1.04)
Year of diagnosis
1988–1994	Reference
1995–2001	3.47 (2.60, 4.62)
2002–2008	5.34 (4.02, 7.09)
2009–2014	6.56 (4.91, 8.75)
Tumor grade
Grade I	Reference
Grade II	1.29 (1.03, 1.60)
Grade III	1.76 (1.41, 2.21)
Undifferentiated	1.82 (1.22, 2.73)
Histology
Ductal	Reference
Lobular	1.16 (0.97, 1.40)
Tumor size
T1a: ≤0.5cm	Reference
T1b: >0.5–1cm	0.97 (0.76, 1.24)
T1c: >1–2cm	0.61 (0.49, 0.76)
T2: >2–5cm	0.43 (0.34, 0.55)
T3: >5.00 cm	0.38 (0.28, 0.52)
Diffuse	0.58 (0.34, 0.99)
Regional lymph node involvement
Positive	0.58 (0.51, 0.67)
Negative	Reference
ER and PR status
Positive	Reference
Negative	1.76 (1.52, 2.03)

The estimates of odds ratios for unknown groups are not present.

^*Models adjusted for all variables in the table.

CI=confidence interval; ER=estrogen receptor; PR=progesterone receptor.