Table I.
Characteristics of breast cancer cases and controls, RPCI, DBBR, 2004–2007 (Controls matched on age and races)
| Cases, N = 179 | Controls, N = 180 | P valuea | OR (95% CI)b | |
| Age | ||||
| 30–39 | 6 (3.4) | 8 (4.4) | ||
| 40–49 | 43 (24.0) | 42 (23.3) | ||
| 50–59 | 55 (30.7) | 65 (36.1) | ||
| 60–69 | 54 (30.2) | 47 (26.1) | ||
| 70+ | 21 (11.7) | 18 (10.0) | P = 0.764 | |
| Race | ||||
| Caucasian | 168 (93.9) | 170 (94.4) | 1.00 | |
| African-American | 11 (6.2) | 10 (5.6) | P = 0.812 | 0.91 (0.91–2.21) |
| Family history of BRCA | ||||
| No | 122 (68.2) | 142 (78.9) | 1.00 | |
| Yes | 29 (16.2) | 37 (20.6) | P = 0.740 | 0.89 (0.51–1.54) |
| Missing | 28 (15.6) | 1 (0.6) | ||
| Menopausal status | ||||
| Premenopausal | 59 (33.0) | 73 (40.6) | 1.00 | |
| Postmenopausal | 90 (50.3) | 102 (56.7) | P = 0.699 | 1.00 (0.51–1.98) |
| Missing | 30 (16.8) | 5 (2.8) | ||
| Education | ||||
| Below or at high school | 41 (22.9) | 36 (20.0) | 1.00 | |
| Above high school | 107 (59.8) | 143 (79.4) | P = 0.107 | 0.66 (0.39–1.12) |
| Missing | 31 (17.3) | 1 (0.6) | ||
| BMI | ||||
| <25 | 47 (26.3) | 52 (28.9) | 1.00 | |
| 25–29.9 | 43 (24.0) | 63 (35.0) | 0.74 (0.43–1.30) | |
| 30+ | 55 (30.7) | 49 (27.2) | P = 0.200 | 1.27 (0.73–2.24) |
| Missing | 34 (19.0) | 16 (8.9) | ||
| Smoking habit | ||||
| Never | 75 (41.9) | 85 (47.2) | 1.00 | |
| Ever | 74 (41.3) | 87 (58.3) | P = 0.870 | 0.94 (0.61–1.47) |
| Missing | 30 (16.8) | 8 (4.4) | ||
| Pack-years | ||||
| Never smoker | 75 (41.9) | 85 (47.2) | 1.00 | |
| Below medianc | 18 (10.1) | 37 (20.6) | 0.55 (0.29–1.05) | |
| At or above median | 44 (24.6) | 39 (21.7) | P = 0.061 | 1.26 (0.74–2.16) |
| Missing | 42 (23.5) | 19 (10.6) | ||
| Alcohol consumption habit | ||||
| Never | 36 (20.1) | 32 (17.8) | 1.00 | |
| Ever | 115 (64.3) | 147 (82.7) | P = 0.182 | 0.67 (0.39–1.16) |
| Missing | 28 (15.6) | 1 (0.6) | ||
| Alcohol consumption frequency | ||||
| Never | 36 (20.1) | 32 (17.8) | 1.00 | |
| Below mediand | 50 (27.9) | 70 (38.9) | 0.62 (0.34–1.15) | |
| At or above median | 65 (36.3) | 77 (42.8) | P = 0.329 | 0.72 (0.40–1.29) |
| Missing | 28 (15.6) | 1 (0.6) | ||
| Age at menarche | ||||
| <13 | 71 (39.7) | 89 (49.4) | 1.00 | |
| 13+ | 77 (43.0) | 78 (43.3) | P = 0.346 | 1.22 (0.78–1.91) |
| Missing | 31 (17.3) | 13 (7.2) | ||
| Age at first birth | ||||
| <25 | 76 (42.5) | 76 (42.2) | 1.00 | |
| 25+ | 43 (24.0) | 60 (33.3) | 0.69 (0.41–1.16) | |
| Nulliparous | 28 (15.6) | 38 (21.1) | P = 0.356 | 0.74 (0.41–1.34) |
| Missing | 32 (17.9) | 6 (3.3) | ||
| Parity | ||||
| 1–2 children | 69 (38.6) | 74 (41.1) | 1.00 | |
| 3+ | 52 (29.0) | 64 (35.6) | 1.25 (0.69–2.26) | |
| Nulliparous | 28 (15.6) | 38 (21.1) | P = 0.707 | 1.06 (0.57–1.97) |
| Missing | 30 (16.8) | 4 (2.2) | ||
| Age at menopausee | ||||
| <50 | 37 (41.1) | 54 (52.9) | 1.00 | |
| 50+ | 45 (50.0) | 45 (44.1) | P = 0.207 | 1.41 (0.78–2.54) |
| Missing | 8 (8.9) | 3 (2.9) | ||
| HRTe | ||||
| Never | 44 (48.9) | 43 (42.1) | 1.00 | |
| Ever | 44 (48.9) | 58 (56.7) | P = 0.307 | 0.73 (0.41–1.30) |
| Missing | 2 (2.2) | 1 (1.0) | ||
| Multivitamin use | ||||
| Never or occasionally | 67 (37.3) | 60 (33.3) | 1.00 | |
| Regularly | 84 (46.9) | 118 (65.6) | P = 0.048 | 0.63 (0.40–0.98) |
| Missing | 28 (15.6) | 2 (1.1) | ||
| Histological grade | ||||
| I | 18 (10.1) | |||
| II | 51 (28.5) | |||
| III | 108 (60.3) | |||
| AJCC stage | ||||
| I | 115 (64.3) | |||
| II | 57 (31.8) | |||
| III | 7 (3.9) | |||
| Hormone status | ||||
| ER+/PR+ | 111 (62.0) | |||
| ER+/PR− or ER−/PR+ | 23 (12.9) | |||
| ER−/PR− | 41 (22.9) | |||
| Tumor size | ||||
| <1 cm | 138 (77.1) | |||
| 1–2 cm | 38 (21.2) | |||
| 2 cm+ | 3 (1.7) | |||
| Lymph node involvement | ||||
| No | 135 (75.4) | |||
| Yes | 44 (24.6) | |||
| Metastasis | ||||
| No | 179 (100.0) |
AJCC, American Joint Committee on Cancer; BMI, body mass index; BRCA, breast cancer; HRT, hormone replacement therapy.
a
P value by Chi-square test.
b
OR adjusting for age and race.
c
Median pack-year = 9.7 pack-year.
d
Median total alcohol consumption frequency = 1.7 per week for alcohol consumption.
e
Among postmenopausal women.