Table 1 Characteristics of 173 study participants with breast cancer in the Multiethnic Cohort
Characteristica | Original study | Involution study | No involution | Partial involution | Complete involution | P valueb |
|---|---|---|---|---|---|---|
(0%) | (1–74%) | (≥75%) | ||||
Sample size (%) | 279 | 173 | 32 (18.5) | 89 (51.4) | 52 (30.1) | N/A |
Age at diagnosis | ||||||
< 50 years | 24 (8.6) | 15 (8.7) | 7 (21.9) | 7 (7.9) | 1 (1.9) | 0.01 |
50 to <55 years | 56 (20.1) | 42 (24.3) | 6 (18.8) | 25 (28.1) | 11 (21.2) | |
55 to <60 years | 55 (19.7) | 40 (23.1) | 12 (37.5) | 18 (20.2) | 10 (19.2) | |
60 to <65 years | 44 (14.3) | 31 (17.9) | 3 (9.4) | 17 (19.1) | 11 (21.2) | |
65+ years | 104 (37.3) | 45 (26.0) | 4 (12.5) | 22 (24.7) | 19 (36.5) | |
Menopausal status (%) | ||||||
Premenopausal | 76 (27.2) | 53 (30.6) | 12 (37.5) | 28 (31.5) | 13 (25.0) | 0.47 |
Postmenopausal | 203 (72.8) | 120 (69.4) | 20 (62.5) | 61 (68.5) | 39 (75.0) | |
Ethnicity (%) | ||||||
Caucasian | 97 (34.8) | 58 (33.5) | 7 (21.9) | 35 (39.3) | 16 (30.8) | 0.39 |
Japanese American | 121 (43.4) | 80 (46.2) | 16 (50.0) | 39 (43.8) | 25 (48.1) | |
Native Hawaiian | 36 (12.9) | 19 (11.0) | 6 (18.8) | 6 (6.7) | 7 (13.5) | |
Other | 25 (8.9) | 16 (9.3) | 3 (9.4) | 9 (7.7) | 4 (7.7) | |
Parity | ||||||
Nulliparous | 47 (16.9) | 25 (14.4) | 6 (18.8) | 8 (9.0) | 11 (21.2) | 0.16 |
1–2 children | 110 (39.4) | 69 (39.9) | 15(46.9) | 38 (42.7) | 16 (30.8) | |
3 or more children | 122 (43.7) | 79 (45.7) | 11 (34.4) | 43 (48.3) | 25 (46.1) | |
Hormone use (%) | ||||||
Never | 102 (36.5) | 59 (34.1) | 9 (28.1) | 28 (31.5) | 22 (42.3) | 0.58 |
Estrogen | 97 (34.8) | 62 (35.8) | 11 (34.4) | 34 (38.2) | 17 (32.7) | |
Estrogen/progesterone | 80 (28.7) | 52 (30.1) | 12 (37.5) | 27 (30.3) | 13 (25.0) | |
Body mass index | ||||||
< 25 kg/m2 | 167 (59.9) | 104 (60.1) | 18 (56.3) | 56 (62.9) | 30 (57.7) | 0.60 |
25 to <30 kg/m2 | 81 (29.0) | 54 (31.2) | 12 (37.5) | 27 (30.3) | 17 (28.9) | |
30+ kg/m2 | 31 (11.1) | 15 (8.7) | 2 (6.3) | 6 (6.7) | 7 (13.5) | |
Tumor stage (%) | ||||||
In situ | 61 (21.9) | 39 (22.6) | 10 (31.3) | 18 (20.2) | 11 (21.2) | 0.60 |
Localized | 169 (60.6) | 105 (60.7) | 20 (62.5) | 53 (59.6) | 32 (61.5) | |
Advanced | 37 (13.2) | 21 (12.1) | 2 (6.3) | 13 (14.6) | 6 (11.5) | |
Missing | 12 (4.3) | 8 (4.6) | 0 (0.0) | 5 (5.6) | 3 (5.8) | |
Mammographic measures | ||||||
Percent density | 37.6 | 41.2 | 38.8 | 42.8 | 40.0 | 0.96 |
Dense area (cm2) | 37.8 | 40.8 | 32.6 | 41.6 | 44.7 | 0.04 |
Non-dense area (cm2) | 77.5 | 67.8 | 63.9 | 64.9 | 75.1 | 0.24 |
Total area (cm2) | 115.3 | 108.6 | 96.5 | 106.4 | 119.5 | 0.02 |