Table 1.
Baseline and tumour characteristics of breast cancer survivors in the EPIC cohort.
| All breast cancer survivors N = 13,270 | |||
|---|---|---|---|
| n | % | ||
| Age at diagnosis (years) | <50 | 1342 | 10.1 |
| 50–<55 | 2049 | 15.4 | |
| 55–<60 | 2671 | 20.1 | |
| 60–<65 | 2878 | 21.7 | |
| 65–<70 | 2332 | 17.6 | |
| ≥70 | 1998 | 15.1 | |
| Educational level | None/primary | 3281 | 24.7 |
| Technical/professional | 3035 | 22.9 | |
| Secondary | 3200 | 24.1 | |
| Longer education | 3143 | 23.7 | |
| Unknown | 611 | 4.6 | |
| Smoking status and intensity (cig/day or years) | Never | 5940 | 44.8 |
| Current, 1–15 cig/day | 1593 | 12.0 | |
| Current, 16–25 cig/day | 749 | 5.6 | |
| Current, 26+ cig/day | 134 | 1.0 | |
| Former, quit ≤10 years | 1063 | 8.0 | |
| Former, quit 11–20 years | 977 | 7.4 | |
| Former, quit 20+ years | 1099 | 8.3 | |
| Miscellaneousa | 1487 | 11.2 | |
| Unknown | 228 | 1.7 | |
| Alcohol consumption g/day | Non-drinker | 1774 | 13.4 |
| >0–3 | 3820 | 28.8 | |
| >3–12 | 4066 | 30.6 | |
| >12–24 | 2069 | 15.6 | |
| >24 | 1541 | 11.6 | |
| BMI (kg/m2) | Underweight <18 | 206 | 1.6 |
| Normal-weight 18 to <25 | 7612 | 57.4 | |
| Overweight 25 to <30 | 3943 | 29.7 | |
| Obesity ≥30 | 1509 | 11.4 | |
| Physical activity | Inactive | 2673 | 20.1 |
| Moderate inactive | 4720 | 35.6 | |
| Moderate active | 3606 | 27.2 | |
| Active | 2076 | 15.6 | |
| Unknown | 195 | 1.5 | |
| Menopausal status at diagnosis | Premenopausal | 3070 | 23.1 |
| Postmenopausal | 10,200 | 76.9 | |
| Ever use of menopause hormone replacement treatment | No | 7487 | 56.4 |
| Yes | 5323 | 40.1 | |
| Unknown | 460 | 3.5 | |
| Grade of tumour | Well-differentiated | 1298 | 9.8 |
| Moderately differentiated | 2917 | 22.0 | |
| Poorly diff/Undiff | 2503 | 18.9 | |
| Not determined | 6552 | 49.4 | |
| Stage of tumour | Stage 0/I | 1954 | 14.7 |
| Stage II | 1593 | 12.0 | |
| Stage III | 303 | 2.3 | |
| Non-metastatic unk. stage | 3984 | 30.0 | |
| Stage IV | 1777 | 13.4 | |
| Unknown | 3659 | 27.6 | |
| ER status | Negative | 1678 | 12.6 |
| Positive | 7500 | 56.5 | |
| Unknown | 4092 | 30.8 | |
| PR status | Negative | 2612 | 19.7 |
| Positive | 5072 | 38.2 | |
| Unknown | 5586 | 42.1 | |
| HER2 status | Negative | 3587 | 27 |
| Positive | 856 | 6.5 | |
| Unknown | 8827 | 66.5 | |
BMI body mass index, cig cigarette, diff differentiated, Undiff undifferentiated, ER oestrogen receptor, PR progesterone receptor, HER2 human epidermal growth factor receptor 2.
aCurrent smoker of cigars, pipes and occasional current smokers, current smokers with missing information on the intensity.