Table 1.
Demographic and clinical characteristics among breast cancer survivors who provided smoking data (n = 9975)*
| Characteristics | WHEL | LACE | NHS | All |
|---|---|---|---|---|
| Age at diagnosis, y, mean (SD) | 51.3 (8.8) | 59.3 (11.0) | 64.8 (7.7) | 59.2 (10.6) |
| Age at smoking questionnaire, y, mean (SD) | 53.3 (9.0) | 60.2 (11.0) | 65.8 (7.8) | 60.7 (10.5) |
| Age at questionnaire, y, range | 27–74 | 27–82 | 44–84 | 27–84 |
| Cancer stage, No. (%) | ||||
| I | 1184 (38.7) | 1052 (46.6) | 2752 (59.1) | 4988 (50.0) |
| II | 1391 (45.5) | 952 (42.1) | 1287 (27.6) | 3630 (36.4) |
| III | 482 (15.8) | 254 (11.2) | 415 (8.9) | 1151 (11.5) |
| Unspecified | 0 | 1 (0.0) | 205 (4.4) | 206 (2.1) |
| Tumor grade, No. (%) | ||||
| Well differentiated | 481 (15.7) | 428 (19.0) | 811 (17.4) | 1720 (17.2) |
| Moderately differentiated | 1231 (40.3) | 941 (41.7) | 1572 (33.7) | 3744 (37.5) |
| Poorly differentiated | 1092 (35.7) | 676 (29.9) | 1122 (24.2) | 2895 (29.0) |
| Unspecified | 253 (8.3) | 214 (9.5) | 1149 (24.7) | 1616 (16.2) |
| Tumor hormone receptors, No. (%) | ||||
| ER+/PR+ | 1894 (62.0) | 1526 (67.6) | 2718 (58.3) | 6138 (61.5) |
| ER+/PR− | 366 (12.0) | 318 (14.1) | 669 (14.4) | 1353 (13.6) |
| ER−/PR+ | 126 (4.1) | 41 (1.8) | 120 (2.6) | 287 (2.9) |
| ER−/PR− | 606 (19.8) | 350 (15.5) | 648 (13.9) | 1604 (16.1) |
| Unspecified | 65 (2.1) | 24 (1.1) | 503 (10.8) | 592 (5.9) |
| Cancer treatment, No. (%) | ||||
| Radiation only | 588 (19.2) | 566 (25.1) | 1652 (35.5) | 2806 (28.1) |
| Chemotherapy only | 841 (27.5) | 435 (19.3) | 625 (13.4) | 1901 (19.1) |
| Radiation and chemotherapy | 1288 (42.1) | 856 (37.9) | 1011 (21.7) | 3155 (31.6) |
| Neither radiation nor chemotherapy | 334 (10.9) | 401 (17.8) | 1062 (22.8) | 1797 (18.0) |
| Unspecified | 2 (0.1) | 1 (0.0) | 307 (6.6) | 310 (3.1) |
| Surgery type, No. (%) | ||||
| Mastectomy | 1599 (52.3) | 1115 (49.4) | 2013 (43.2) | 4727 (47.4) |
| Breast conserving | 1457 (47.7) | 1144 (50.6) | 2376 (51.0) | 4977 (49.9) |
| Unspecified | 0 | 0 | 236 (5.1) | 236 (2.4) |
| Diagnosis menopause status, No. (%) | ||||
| Premenopausal | 1555 (50.9) | 513 (22.7) | 217 (4.7) | 2285 (23.9) |
| Postmenopausal | 1414 (46.3) | 1436 (6.6) | 4314 (92.6) | 7164 (71.8) |
| Equivocal | 88 (2.9) | 310 (13.7) | 128 (2.7) | |
* ER = estrogen receptor; LACE = Life After Cancer Study; NHS = Nurses Health Study; PR = progesterone receptor; WHEL = Women’s Healthy Eating and Living Study; SD = standard deviation.