Table 1.
Descriptive characteristics of 4,216 women included in the COMBO study by SBCE status
| SBCE† | |||
|---|---|---|---|
| All women N=4,216 |
No (n=3,658) | Yes (n=558) | |
| Characteristics at incident breast cancer diagnosis | |||
| Year of diagnosis | |||
| 1990–1994 | 950 (22.5) | 755 (20.6) | 195 (34.9) |
| 1995–1999 | 1191 (28.2) | 1020 (27.9) | 171 (30.6) |
| 2000–2004 | 1201 (28.5) | 1073 (29.3) | 128 (22.9) |
| 2005–2008 | 874 (20.7) | 810 (22.1) | 64 (11.5) |
| Age at diagnosis, years | |||
| Median (interquartile range) | 63 (52–73) | 63 (52–73) | 62 (50–72) |
| 18–39 | 139 (3.3) | 112 (3.1) | 27 (4.8) |
| 40–49 | 646 (15.3) | 544 (14.9) | 102 (18.3) |
| 50–59 | 995 (23.6) | 866 (23.7) | 129 (23.1) |
| 60–69 | 1018 (24.1) | 889 (24.3) | 129 (23.1) |
| 70–79 | 940 (22.3) | 824 (22.5) | 116 (20.8) |
| 80+ | 478 (11.3) | 423 (11.6) | 55 (9.9) |
| Menopausal status at diagnosis | |||
| Peri- or Premenopausal | 1145 (27.2) | 956 (26.1) | 189 (33.9) |
| Postmenopausal | 3071 (72.8) | 2702 (73.9) | 369 (66.1) |
| Body mass index (kg/m2) | |||
| Mean (SD) | 28 (6.2) | 28 (6.2) | 28.3 (6.6) |
| Median | 26.8 | 26.7 | 27.5 |
| <18.5 | 69 (1.6) | 55 (1.5) | 14 (2.5) |
| 18.5–24.9 | 1453 (34.6) | 1269 (34.8) | 184 (33.3) |
| 25.0–29.9 | 1362 (32.5) | 1186 (32.6) | 176 (31.8) |
| 30.0–34.9 | 766 (18.3) | 666 (18.3) | 100 (18.1) |
| 35+ | 546 (13.0) | 467 (12.8) | 79 (14.3) |
| Unknown | 20 | 15 | 5 |
| Smoking status at diagnosis | |||
| Current | 253 (6.0) | 230 (6.3) | 23 (4.1) |
| Past | 352 (8.3) | 318 (8.7) | 34 (6.1) |
| Never/Unknown | 3611 (85.6) | 3110 (85.0) | 501 (89.8) |
| AJCC stage | |||
| I | 2648 (62.8) | 2384 (65.2) | 264 (47.3) |
| IIA | 1078 (25.6) | 906 (24.8) | 172 (30.8) |
| IIB | 490 (11.6) | 368 (10.1) | 122 (21.9) |
| ER/PR status | |||
| ER(−)/PR(−) | 667 (15.8) | 531 (14.5) | 136 (24.4) |
| ER(+)/PR(−) | 383 (9.1) | 319 (8.7) | 64 (11.5) |
| ER(−)/PR(+) | 61 (1.4) | 47 (1.3) | 14 (2.5) |
| ER(+)/PR(+) | 2888 (68.5) | 2572 (70.3) | 316 (56.6) |
| ER and/or PR unknown | 217 (5.1) | 189 (5.2) | 28 (5.0) |
| HER2 status | |||
| Test performed | 2074 (79.7) | 1874 (80.5) | 200 (73.0) |
| Positive/borderline | 353 (17.0) | 311 (16.6) | 42 (21.0) |
| Negative | 1714 (82.6) | 1556 (83.0) | 158 (79.0) |
| No result | 7 (0.3) | 7 (0.4) | 0 (0.0) |
| Surgical procedure | |||
| Mastectomy including radical ± radiation | 1521 (36.1) | 1289 (35.2) | 232 (41.6) |
| Breast conserving, + radiation | 2172 (51.5) | 1927 (52.7) | 245 (43.9) |
| Breast conserving, no radiation | 523 (12.4) | 442 (12.1) | 81 (14.5) |
| Other treatment | |||
| Any chemotherapy | 1376 (32.6) | 1142 (31.2) | 234 (41.9) |
| Completed course | 1212 (88.1) | 1003 (87.8) | 209 (89.3) |
| Any endocrine therapy | 2363 (56.0) | 2101 (57.4) | 262 (47.0) |
| Charlson score at diagnosis | |||
| 0 | 3229 (76.6) | 2784 (76.1) | 445 (79.7) |
| 1 | 704 (16.7) | 625 (17.1) | 79 (14.2) |
| 2+ | 283 (6.7) | 249 (6.8) | 34 (6.1) |
| Diabetes | |||
| Diabetes (ever) throughout follow-up | 610 (14.5) | 539 (14.7) | 71 (12.7) |
| At BC diagnosis (year prior to BC) | 329 (53.9) | 294 (54.5) | 35 (49.3) |
| After BC diagnosis through follow-up | 281 (46.1) | 245 (45.5) | 36 (50.7) |
| Diabetes medication use in year prior to breast cancer diagnosis* | |||
| Any oral or injectable medications | 277 (6.6) | 241 (6.6) | 36 (6.5) |
| Any oral medications | 225 (5.3) | 200 (5.5) | 25 (4.5) |
| Metformin | 106 (47.1) | 97 (48.5) | 9 (36.0) |
| Sulfonylurea | 175 (77.8) | 152 (76.0) | 23 (92.0) |
| Insulin | 103 (2.4) | 88 (2.4) | 15 (2.7) |
| Long-acting | 12 (11.7) | 11 (12.5) | 1 (6.7) |
| Short-acting | 88 (85.4) | 74 (84.1) | 14 (93.3) |
| Rapid-acting | 16 (15.5) | 13 (14.8) | 3 (20.0) |
| Characteristics throughout follow-up | |||
| Diabetes medication use throughout follow-up* | |||
| Any oral or injectable medications | 464 (11.0) | 408 (11.2) | 56 (10.0) |
| Any oral medications | 403 (9.6) | 358 (9.8) | 45 (8.1) |
| Metformin | 275 (68.2) | 248 (69.3) | 27 (60.0) |
| Sulfonylurea | 307 (76.2) | 270 (75.4) | 37 (82.2) |
| Insulin | 246 (5.8) | 218 (6.0) | 28 (5.0) |
| Long-acting | 47 (19.1) | 43 (19.7) | 4 (14.3) |
| Short-acting | 198 (80.5) | 173 (79.4) | 25 (89.3) |
| Rapid-acting | 62 (25.2) | 56 (25.7) | 6 (21.4) |
| % Follow-up years with yearly screening mammogram | |||
| <50% | 939 (22.3) | 793 (21.7) | 146 (26.2) |
| 50%–80% | 1439 (34.1) | 1284 (35.1) | 155 (27.8) |
| >80% | 1838 (43.6) | 1581 (43.2) | 257 (46.1) |
| Years of follow-up | |||
| Mean (SD) | 7.1 (4.3) | 7.5 (4.3) | 4.4 (3.5) |
| Median | 6.3 | 6.7 | 3.3 |
†
SBCE = second breast cancer event includes recurrence or second primary breast cancer, in situ and invasive.
*
Not mutually exclusive