Table 1.
Selected breast cancer case characteristics by smoking status
| Characteristic | Current smokers (N = 125) No. (%) | Former smokers (N = 124) No. (%) | Never smokers (N = 268) No. (%) | p-value | |
|---|---|---|---|---|---|
| Case characteristics | |||||
| Age, mean (SD) | 46.9 (10.6) | 51.0 (11.3) | 50.4 (12.5) | 0.009 | |
| Age | 50+ years | 35 (28.0) | 53 (42.7) | 111 (41.4) | 0.02 |
| <50 years | 90 (72.0) | 71 (57.3) | 157 (58.6) | ||
| Race | White/Othera | 76 (60.8) | 77 (62.1) | 148 (55.2) | 0.35 |
| Black | 49 (39.2) | 47 (37.9) | 120 (44.8) | ||
| Menopausal status | Postmenopausal | 55 (44.0) | 59 (47.6) | 128 (47.8) | 0.77 |
| Premenopausal | 70 (56.0) | 65 (52.4) | 140 (52.2) | ||
| Alcohol consumption | Never | 16 (12.8) | 21 (16.9) | 113 (42.2) | < 0.0001 |
| Ever | 109 (87.2) | 103 (83.1) | 155 (57.8) | ||
| Body mass index (BMI) | <25 (normal) | 60 (48.0) | 39 (32.2) | 86 (33.0) | 0.05 |
| 25 to <30 (overweight) | 29 (23.2) | 36 (29.8) | 80 (30.7) | ||
| >30 (obese) | 36 (28.8) | 46 (38.0) | 95 (36.4) | ||
| Smoking characteristics | |||||
| Cigarettes/day | <1/2 pack | 32 (25.6) | 51 (41.5) | – | 0.02 |
| 1/2–1 pack | 49 (39.2) | 44 (35.8) | – | ||
| >1 pack | 44 (35.2) | 28 (22.8) | – | ||
| Duration of smoking (yrs) | <10 | 19 (15.2) | 59 (48.0) | – | < 0.0001 |
| 11–20 | 22 (17.6) | 29 (23.6) | – | ||
| >20 | 84 (67.2) | 35 (28.5) | – | ||
| Time since quitting (yrs) | ≤10 | – | 54 (43.6) | – | – |
| 11+ | – | 70 (56.4) | – | ||
| Age at initiation (yrs) | <15 | 31 (24.8) | 13 (10.5) | – | 0.0008 |
| 16–20 | 54 (43.2) | 81 (65.3) | – | ||
| >20 | 40 (32.0) | 30 (24.2) | – | ||
| Clinical characteristics | |||||
| Stageb | I | 45 (39.5) | 45 (39.8) | 88 (34.7) | 0.52 |
| II | 51 (44.7) | 55 (48.7) | 139 (54.7) | ||
| III | 15 (13.2) | 9 (8.0) | 21 (8.3) | ||
| IV | 3 (2.6) | 4 (3.5) | 6 (2.4) | ||
| ER/PR status | ER+/PR+ | 59 (49.6) | 69 (58.1) | 122 (46.6) | 0.38 |
| ER+/PR− | 15 (12.6) | 9 (7.6) | 24 (9.2) | ||
| ER−/PR+ | 8 (6.7) | 7 (5.9) | 24 (9.2) | ||
| ER−/PR− | 37 (31.1) | 34 (28.6) | 92 (35.1) | ||
| Intrinsic subtype | |||||
| All cases | Luminal A | 54 (54.0) | 52 (53.6) | 106 (49.1) | 0.99 |
| Luminal B | 15 (15.0) | 14 (14.4) | 36 (16.7) | ||
| Basal-like | 19 (19.0) | 20 (20.6) | 47 (21.8) | ||
| HER2+/ER− | 6 (6.0) | 5 (5.2) | 15 (6.9) | ||
| Unclassified | 6 (6.0) | 6 (6.2) | 12 (5.5) | ||
| Black | Luminal A | 19 (52.8) | 18 (47.4) | 44 (46.3) | 0.79 |
| Luminal B | 4 (11.1) | 4 (10.5) | 14 (14.7) | ||
| Basal-like | 9 (25.0) | 12 (31.6) | 25 (26.3) | ||
| HER2+/ER− | 4 (11.1) | 3 (7.9) | 6 (6.3) | ||
| Unclassified | 0 (0) | 1 (2.6) | 6 (6.3) | ||
| White/other | Luminal A | 35 (54.7) | 34 (57.6) | 62 (51.2) | 0.83 |
| Luminal B | 11 (17.2) | 10 (17.0) | 22 (18.2) | ||
| Basal-like | 10 (15.6) | 8 (13.6) | 22 (18.2) | ||
| HER2+/ER− | 2 (3.1) | 2 (3.4) | 9 (7.4) | ||
| Unclassified | 6 (9.4) | 5 (8.5) | 6 (5.0) | ||
a
The white/other cases included 291 Caucasians, 3 American Indians, 6 Asians, and 1 other
b
According to the AJCC breast tumor staging guidelines. The differences between column totals and numbers within some categories are due to missing data in some cases for some variables