Selected characteristics of controls, invasive ductal carcinoma cases, and invasive lobular carcinoma cases
| Controls (n = 1,474) | Ductal carcinoma (n = 1,199) | Lobular carcinoma (n = 739) | ||||
|---|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | ||||
| Reference age (y) | ||||||
| 55-59 | 137 (9.3) | 140 (11.7) | 162 (21.9) | |||
| 60-64 | 121 (8.2) | 125 (10.4) | 139 (18.8) | |||
| 65-69 | 442 (30.0) | 341 (28.4) | 189 (25.5) | |||
| 70-74 | 478 (32.4) | 380 (31.7) | 195 (26.4) | |||
| 75-79 | 296 (20.1) | 213 (17.7) | 54 (7.3) | |||
| Race | ||||||
| White (non-Hispanic) | 1,346 (91.3) | 1,116 (93.1) | 688 (93.1) | |||
| Black | 45 (3.1) | 22 (1.8) | 16 (2.2) | |||
| Asian/Pacific Islander | 38 (2.6) | 35 (2.9) | 11 (1.5) | |||
| Other/unknown | 45 (3.0) | 26 (2.2) | 24 (3.2) | |||
| Education | ||||||
| Less than high school | 177 (12.0) | 127 (10.6) | 53 (7.2) | |||
| High school | 520 (35.3) | 403 (33.6) | 221 (29.9) | |||
| Some college | 467 (31.7) | 407 (33.9) | 238 (32.2) | |||
| College/college graduate | 309 (21.0) | 262 (21.9) | 227 (30.7) | |||
| Missing | 1 | 0 | 0 | |||
| Parity | ||||||
| Nulliparous | 130 (8.8) | 126 (10.5) | 99 (13.4) | |||
| Parous | 1,344 (91.2) | 1,073 (89.5) | 640 (86.6) | |||
| Age at first birth (y) | ||||||
| 14-19 | 273 (20.4) | 201 (18.8) | 124 (19.5) | |||
| 20-24 | 650 (48.5) | 519 (48.6) | 306 (48.0) | |||
| 25-29 | 305 (22.7) | 244 (22.8) | 136 (21.4) | |||
| 30-42 | 113 (8.4) | 105 (9.8) | 71 (11.1) | |||
| Missing | 133 | 130 | 102 | |||
| Use of oral contraceptives (mo) | ||||||
| 0 | 907 (63.4) | 721 (63.0) | 339 (49.2) | |||
| 6-59 | 297 (20.8) | 219 (19.1) | 193 (28.0) | |||
| 60-409 | 227 (15.9) | 204 (17.8) | 157 (22.8) | |||
| Missing | 43 | 55 | 50 | |||
| Recency of menopausal hormone therapy use | ||||||
| Never user | 433 (32.4) | 323 (29.9) | 134 (19.3) | |||
| Former user of hormone therapy | 246 (18.4) | 185 (17.1) | 96 (13.9) | |||
| Current EHT user | 450 (33.6) | 297 (27.5) | 195 (28.1) | |||
| Current CHT user | 209 (15.6) | 276 (25.5) | 268 (38.7) | |||
| Missing | 136 | 118 | 46 | |||
| First-degree family history of breast cancer | ||||||
| No | 1,153 (83.4) | 878 (77.3) | 556 (77.3) | |||
| Yes | 229 (16.6) | 258 (22.7) | 163 (22.7) | |||
| Missing | 92 | 63 | 20 | |||
| Body mass index, quartiles (kg/m2) | ||||||
| ≤23.16 | 363 (25.4) | 265 (22.6) | 210 (29.0) | |||
| 23.17-26.44 | 372 (26.1) | 309 (26.4) | 154 (21.3) | |||
| 26.45-30.82 | 343 (24.0) | 283 (24.1) | 200 (27.6) | |||
| ≥30.83 | 350 (24.5) | 315 (26.9) | 160 (22.1) | |||
| Missing | 46 | 27 | 15 | |||
Abbreviations: EHT, estrogen hormone therapy; CHT, combined hormone therapy.