Table 3.

Characteristics of participants at baseline, by those who had a 20% or greater relative reduction in breast density at 12 months (or 6 months, if 12 month data not available) and those who did not

<20% reduction or increase≥20% reduction
n = 32n = 18P
Age—median (range)63 (47–79)60.5 (53–75)0.26
BMI—median (range)25.9 (20.6–41.7)29.5 (23–49.6)0.07
Race—no. (%)
 White26 (81)17 (94)0.41
 African-American5 (16)1 (6)
 Other1 (3)0 (0)
Type of surgery–no. (%)
 Mastectomy9 (28)4 (22)0.90
 Lumpectomy/radiation23 (72)14 (78)
Stage—no. (%)
 DCIS/LCIS9 (28)3 (17)0.65
 I19 (59)12 (67)
 II4 (12)3 (17)
Nodal status—no. (%)
 Positive node2 (6)2 (11)0.45
 Negative node22 (69)14 (78)
 Not done8 (25)2 (11)
Histology—no. (%)
 DCIS8 (25)3 (17)0.74
 Infiltrating ductal18 (56)13 (72)
 Infiltrating lobular4 (12)2 (11)
 Mixed1 (3)0 (0)
 Other (colloid)1 (3)0 (0)
Grade—no. (%)
 112 (38)6 (33)0.45
 217 (53)8 (44)
 33 (9)4 (22)
Markers—no. (%)
 ER+/PR+27 (84)16 (89)0.25
 ER+/PR−5 (16)1 (6)
 ER−/PR+0 (0)1 (6)
Genotype—no. (%)
 AA2 (6)2 (11)0.63
 AC8 (25)6 (33)
 CC22 (69)10 (56)
Baseline CLB density (%)—median (range)10 (0–70)10 (0–50)0.41
Estradiol (pmol/L)—median (range)18 (6.9–102)25 (7.2–112)0.36
Estrone sulfate (pmol/L)—median (range)603 (214–3,086)736.5 (173–3,500)0.90

NOTE: Values are n (%) for categories and median (range) for continuous measurements. P values for Fisher's exact test for comparisons of categorical characteristics and for Wilcoxon rank sum tests for comparisons of continuously measured characteristics.

Abbreviation: LCIS: Lobular carcinoma in situ.