Table 1.
Characteristics of hospital-based cohort of 14,645 breast cancer patients by year of breast cancer diagnosis
| Year of breast cancer diagnosis | ||||||||
|---|---|---|---|---|---|---|---|---|
| Total | 1970–1986 | 1987–1999 | 2000–2009 | |||||
| Characteristic | No. | % | No. | % | No. | % | No. | % |
| Total no. of patients | 14,645 | 100 | 3571 | 100 | 6626 | 100 | 4448 | 100 |
| Age at diagnosis (years) | ||||||||
| Median (IQR) | 47 (42–52) | 47 (42–53) | 46 (41–50) | 51 (45–56) | ||||
| <35 yearsa | 1010 | 6.9 | 236 | 6.6 | 562 | 8.5 | 212 | 4.8 |
| 35–40 years | 1568 | 10.7 | 433 | 12.1 | 813 | 12.3 | 322 | .2 |
| 40–49 years | 6586 | 45.0 | 1600 | 44.8 | 3486 | 52.6 | 1500 | 33.7 |
| 50–61 years | 5481 | 37.4 | 1302 | 36.5 | 1765 | 26.6 | 2414 | 54.3 |
| Stage | ||||||||
| Ductal carcinoma in situ | 929 | 6.3 | 40 | 1.1 | 318 | 4.8 | 571 | 12.8 |
| I | 4436 | 30.3 | 327 | 9.2 | 2168 | 32.7 | 1941 | 43.6 |
| II | 5251 | 35.9 | 433 | 12.1 | 3427 | 51.7 | 1391 | 31.3 |
| IIIa | 497 | 24.1 | 4 | 0.1 | 256 | 3.9 | 308 | 5.3 |
| Unknown | 3532 | 3.4 | 2767 | 77.5 | 457 | 6.9 | 237 | 6.9 |
| Type of surgery b | ||||||||
| Mastectomy | 8186 | 55.9 | 1139 | 31.9 | 4178 | 63.1 | 2869 | 64.5 |
| Wide local excision | 5127 | 35.0 | 2423 | 67.9 | 1639 | 24.7 | 1065 | 23.9 |
| Type of surgery unknown | 1332 | 9.1 | 9 | 0.3 | 809 | 12.2 | 514 | 11.6 |
| Radiation therapy and chemotherapy b | ||||||||
| None | 1663 | 11.4 | 439 | 12.3 | 578 | 8.7 | 646 | 14.5 |
| Radiation therapy alone | 8137 | 55.6 | 2513 | 70.4 | 3502 | 52.9 | 2122 | 47.7 |
| Chemotherapy alone | 406 | 2.8 | 19 | 0.5 | 216 | 3.3 | 171 | 3.8 |
| Radiation therapy and chemotherapy | 4439 | 30.3 | 600 | 16.8 | 2330 | 35.2 | 1509 | 33.9 |
| Radiation fields b | ||||||||
| No radiation therapy | 2069 | 14.2 | 458 | 12.8 | 794 | 12.0 | 817 | 18.4 |
| Breast, no IMC | 6301 | 43.0 | 621 | 17.4 | 3285 | 49.6 | 2395 | 53.8 |
| Typical mean heart dose left/right (Gy) | 4.8/0.6 Gy | 4.3/0.6 Gy | 4.8/0.7 Gy | 1.5/0.3 Gy | ||||
| Chest wall, no IMC | 796 | 5.4 | 337 | 9.4 | 382 | 5.8 | 77 | 1.7 |
| Typical mean heart dose left/right (Gy) | 5.8/2.8 Gy | 4.0/2.8 Gy | 6.3/2.8 Gy | 1.5/0.3 | ||||
| IMC, no chest wall or breast | 2269 | 15.5 | 1164 | 32.6 | 850 | 12.8 | 255 | 5.7 |
| Typical mean heart dose left/right (Gy) | 14.7/8.9 Gy | 12.2/8.9 Gy | 16.5/9.9 Gy | 16.1/9.4 Gy | ||||
| IMC and breast | 1429 | 9.8 | 475 | 13.3 | 679 | 10.3 | 275 | 6.2 |
| Typical mean heart dose left/right (Gy) | 16.6/13.4 Gy | 16.6/15.3 Gy | 21.8/13.4 Gy | 9.1/9.2 Gy | ||||
| IMC and chest wall | 806 | 5.5 | 430 | 12.0 | 226 | 3.4 | 150 | 3.4 |
| Typical mean heart dose left/right (Gy) | 16.1/10.1 Gy | 14.8/12.6 Gy | 16.4/10.5 Gy | 16.1/1.7 Gy | ||||
| Unknown | 975 | 6.7 | 86 | 2.4 | 410 | 6.2 | 479 | 10.8 |
| Chemotherapy regimen b | ||||||||
| No | 9800 | 66.9 | 2952 | 82.7 | 4080 | 61.6 | 2768 | 62.2 |
| CMF-like regimens | 2029 | 13.9 | 619 | 17.4 | 1422 | 21.5 | 0 | 0 |
| Anthracycline-based regimensc | 2816 | 19.2 | 0 | 0 | 1124 | 17.0 | 1680 | 37.8 |
| Endocrine therapy b | ||||||||
| No | 12,205 | 83.3 | 3503 | 98.1 | 6.043 | 91.2 | 2659 | 59.8 |
| Yes | 2440 | 16.7 | 68 | 1.9 | 583 | 8.8 | 1789 | 40.2 |
| Cardiovascular risk factors at breast cancer diagnosis d | ||||||||
| None known | 10,908 | 74.5 | 1875 | 52.5 | 5132 | 77.5 | 3901 | 87.7 |
| Hypertension, hypercholesterolemia or diabetes mellitus | 671 | 4.6 | 355 | 9.9 | 186 | 2.8 | 130 | 2.9 |
| Smokinge | 2966 | 20.3 | 1265 | 35.4 | 1326 | 20.0 | 375 | 8.4 |
| History of cardiovascular disease | 484 | 3.3 | 315 | 8.8 | 82 | 1.3 | 97 | 2.0 |
| Follow-up time (years) | ||||||||
| Median (IQR) | 14 (9–20) | 23 (17–28) | 15 (9–19) | 9 (6–11) | ||||
| 1–4 years | 1297 | 9.8 | 0 | 0 | 917 | 15.1 | 380 | 10.6 |
| 5–9 years | 2604 | 19.7 | 0 | 0 | 723 | 11.9 | 1881 | 52.6 |
| 10–19 years | 5816 | 44.0 | 1344 | 37.7 | 3154 | 52.0 | 1318 | 36.8 |
| 20–29 years | 2979 | 22.5 | 1702 | 47.7 | 1277 | 21.1 | 0 | 0 |
| ≥30 years | 523 | 4.0 | 523 | 14.7 | 0 | 0 | 0 | 0 |
| Vital status | ||||||||
| Alive | 10,064 | 68.7 | 1889 | 52.9 | 4240 | 64.0 | 3935 | 88.5 |
| Deceased | 4580 | 31.3 | 1682 | 47.1 | 2385 | 36.0 | 513 | 11.5 |
IQR interquartile range, IMC internal mammary chain.
aMedian age for patients aged <35 years at diagnosis was 32 years, with an interquartile range of 30–34 years.
bMutually exclusive treatment groups, taking into account primary treatment only.
cIncluding either epirubicin or doxorubicin.
d335 patients had more than one of the mentioned cardiovascular risk factors at breast cancer diagnosis and these patients are listed more than once. The most frequent combinations involved current or previous smoking.
eSmoking defined as quit shortly before breast cancer diagnosis, smoker at breast cancer diagnosis or smoker during follow-up. 17.5 % of the cohort had never smoked. Smoking information was missing for 62.3% of the cohort