Table 2.
Baseline characteristics of patients diagnosed or treated in 2018, 2019, and 2020 (N, %)
| Group 1 Patients diagnosed during:a | Group 2 Patients treated in weeks 2 to 26 of:b |
|||||||
|---|---|---|---|---|---|---|---|---|
| 2018/2019 | Pre-COVID | Transition | Lockdown | Care restart | 2018 | 2019 | 2020 | |
| Patients | 28,661 | 2,347 | 1,020 | 586 | 1,483 | 10,785 | 10,875 | 9,596 |
| Age group | ||||||||
| < 50 | 6,035 (21.1) | 488 (20.8) | 206 (20.2) | 180 (30.7) | 466 (31.4) | 2,787 (25.8) | 2,797 (25.7) | 2,579 (26.9) |
| 50–74 | 19,236 (67.1) | 1,553 (66.2) | 700 (68.6) | 318 (54.3) | 760 (51.3) | 7,029 (65.2) | 7,017 (64.5) | 6,049 (63.0) |
| > 74 | 3,390 (11.8) | 306 (13.0) | 114 (11.2) | 88 (15.0) | 257 (17.3) | 969 (9.0) | 1,061 (9.8) | 968 (10.1) |
| Stage | ||||||||
| DCIS, grade I–II | 2,068 (7.2) | 186 (7.9) | 72 (7.1) | 26 (4.4) | 59 (4.0) | 479 (4.4) | 526 (4.8) | 381 (4.0) |
| DCIS, grade III | 1,561 (5.4) | 133 (5.7) | 55 (5.4) | 22 (3.8) | 43 (2.9) | 463 (4.3) | 449 (4.6) | 348 (3.6) |
| DCIS, grade unknown | 199 (0.7) | 25 (1.1) | 6 (0.6) | 3 (0.5) | 9 (0.6) | 35 (0.3) | 42 (0.4) | 47 (0.5) |
| I | 12,191 (42.5) | 974 (41.5) | 436 (42.8) | 203 (34.6) | 521 (35.1) | 4,068 (37.7) | 3,947 (36.3) | 3,391 (35.3) |
| II | 9,835 (34.3) | 800 (34.1) | 341 (33.4) | 244 (41.6) | 650 (43.8) | 4,282 (39.7) | 4,431 (40.7) | 4,008 (41.8) |
| III | 2,462 (8.6) | 205 (8.7) | 92 (9.0) | 78 (13.3) | 176 (11.9) | 1,280 (11.9) | 1,313 (12.1) | 1,252 (13.1) |
| IV | 334 (1.2) | 24 (1.0) | 17 (1.7) | 10 (1.7) | 25 (1.7) | 173 (1.6) | 163 (1.5) | 167 (1.7) |
| Unknown | 11 (0.0) | 0 (0.0) | 1 (0.1) | 0 (0.0) | 0 (0.0) | 5 (0.1) | 4 (0.0) | 2 (0.0) |
| Screening status | ||||||||
| Screen-detected | 11,914 (41.6) | 949 (40.4) | 467 (45.8) | 67 (11.4) | 32 (2.2) | 4,065 (37.7) | 4,006 (36.8) | 2,987 (31.1) |
| Non-screen-detected | 15,940 (55.6) | 1,322 (56.3) | 515 (50.5) | 503 (85.8) | 1,410 (95.1) | 6,425 (59.6) | 6,533 (60.1) | 6,255 (65.2) |
| Unknown | 807 (2.8) | 76 (3.2) | 38 (3.7) | 16 (2.2) | 41 (2.8) | 295 (2.7) | 336 (3.1) | 354 (3.7) |
| Hormone receptor statusc | ||||||||
| Positive | 20,739 (83.5) | 1,666 (83.2) | 742 (83.7) | 424 (79.3) | 1,107 (80.7) | 8,019 (81.8) | 8,017 (81.3) | 7,059 (80.0) |
| Negative | 3,949 (15.9) | 320 (16.0) | 136 (15.3) | 107 (20.0) | 254 (18.5) | 1,750 (17.8) | 1,799 (18.3) | 1,708 (19.4) |
| Unknown | 145 (0.6) | 17 (0.9) | 9 (1.0) | 4 (0.8) | 11 (0.8) | 39 (0.4) | 42 (0.4) | 53 (0.6) |
| HER2 statusc | ||||||||
| Positive | 3,330 (13.4) | 227 (11.3) | 104 (11.7) | 89 (16.6) | 212 (15.5) | 1,614 (16.5) | 1,561 (15.8) | 1,430 (16.2) |
| Negative | 20,994 (84.5) | 1,734 (86.6) | 765 (86.3) | 437 (81.7) | 1,123 (81.9) | 8,055 (82.1) | 8,149 (82.7) | 7,246 (82.2) |
| Unknown | 509 (2.1) | 42 (2.1) | 18 (2.0) | 9 (1.7) | 37 (2.7) | 139 (1.4) | 148 (1.5) | 144 (1.6) |
| Subtypec | ||||||||
| HR+/HER2+ | 2,277 (9.2) | 160 (8.0) | 70 (7.9) | 59 (11.0) | 145 (10.6) | 1,120 (11.4) | 1,090 (11.1) | 995 (11.3) |
| HR+/HER2− | 18,136 (73.0) | 1,484 (74.1) | 665 (75.0) | 362 (67.8) | 938 (68.4) | 6,804 (69.4) | 6,833 (69.3) | 5,982 (67.8) |
| HR−/HER2+ | 1,049 (4.2) | 67 (3.3) | 34 (3.8) | 30 (5.6) | 67 (4.9) | 494 (5.0) | 471 (4.8) | 434 (4.9) |
| HR−/HER2− | 2,854 (11.5) | 249 (12.4) | 100 (11.3) | 75 (14.0) | 185 (13.5) | 1,249 (12.7) | 1,313 (13.3) | 1,263 (14.3) |
| Unknown | 517 (2.1) | 43 (2.2) | 18 (2.0) | 9 (1.7) | 37 (2.7) | 141 (1.4) | 151 (1.5) | 146 (1.7) |
| Patients with DCIS grade I or II receiving surgery | 1,758 (85.0) | 148 (79.6) | 49 (68.1) | 23 (88.5) | 42 (71.2) | NA | NA | NA |
| Patients with DCIS grade III receiving surgery | 1,533 (98.2) | 129 (97.0) | 55 (100.0) | 21 (95.5) | 43 (100.0) | NA | NA | NA |
| Neo-adjuvant chemotherapyd | 6,142 (24.7) | 492 (24.6) | 167 (18.8) | 187 (35.0) | 483 (35.2) | 1,381 (12.8) | 1,534 (14.1) | 1,335 (13.9) |
| Neo-adjuvant endocrine therapyd | 1,120 (4.5) | 137 (6.8) | 105 (11.8) | 47 (8.8) | 92 (6.7) | 233 (2.2) | 286 (2.6) | 411 (4.3) |
| Neo-adjuvant targeted therapyd | 2,001 (8.1) | 150 (7.5) | 58 (6.5) | 68 (12.7) | 160 (11.7) | 425 (3.9) | 471 (4.3) | 442 (4.6) |
| Breast-conserving surgeryd | 17,136 (69.0) | 1,398 (69.8) | 605 (68.2) | 341 (63.7) | 822 (59.9) | 4,766 (44.2) | 4,932 (45.4) | 4,100 (42.7) |
| Mxd | 7,697 (31.0) | 605 (30.2) | 282 (31.8) | 194 (36.3) | 550 (40.1) | 2,160 (20.0) | 2,104(19.4) | 1,960 (20.4) |
| Mx and IBRd | 2,321 (9.4) | 176 (8.8) | 70 (7.9) | 49 (9.2) | 207 (15.1) | 710 (6.6) | 677 (6.2) | 641 (671) |
| Mx and IBR with autologous tissued | 232 (0.9) | 19 (1.0) | 5 (0.6) | 4 (0.8) | 36 (2.6) | 118 (1.1) | 80 (0.7) | 73 (0.8) |
| Mx and IBR with implantd | 1,950 (7.9) | 144 (7.2) | 60 (6.8) | 38 (7.1) | 156 (11.4) | 554 (5.1) | 574 (5.3) | 516 (5.4) |
| Mx and IBR with autologous tissue and implantd | 90 (0.4) | 2 (0.1) | 1 (0.1) | 3 (0.6) | 5 (0.4) | 33 (0.3) | 16 (0.2) | 20 (0.2) |
| Adjuvant chemotherapyd | 4,215 (17.0) | 336 (16.8) | 189 (21.3) | 101 (18.9) | 267 (19.5) | 1,054 (9.8) | 935 (8.6) | 1,017 (10.6) |
| Adjuvant endocrine therapyd | 12,805 (51.6) | 1,019 (50.9) | 470 (53.0) | 295 (55.1) | 791 (57.6) | 2,945 (27.3) | 2,911 (26.8) | 2,815 (29.3) |
| Adjuvant targeted therapyd | 2,802 (11.3) | 204 (10.2) | 92 (10.4) | 77 (14.4) | 183 (13.3) | 350 (3.3) | 369 (3.4) | 553 (5.8) |
| Adjuvant radiotherapyd | 18,971 (76.4) | 1,506 (75.2) | 671 (75.7) | 410 (76.6) | 989 (72.1) | 4,989 (46.3) | 4,943 (45.5) | 4,731 (49.3) |
| Adjuvant chemotherapy-radiotherapy sequenced | ||||||||
| Chemotherapy first | 1,063 (30.7) | 50 (17.7) | 35 (22.7) | 19 (22.4) | 69 (30.1) | NA | NA | NA |
| Radiotherapy first | 2,351 (67.8) | 229 (80.9) | 116 (75.3) | 60 (70.6) | 156 (68.1) | NA | NA | NA |
| Concurrent | 40 (1.2) | 3 (1.1) | 2 (1.3) | 5 (5.9) | 1 (0.0) | NA | NA | NA |
| Unknown | 14 (0.4) | 1 (0.4) | 1 (0.7) | 1 (1.2) | 3 (1.3) | NA | NA | NA |
Pre-COVID: weeks 1–8, 2020; Transition: weeks 9–12, 2020; Lockdown: weeks 13–17, 2020; Care restart: weeks 18–26, 2020
HER2 Human epidermal growth receptor 2, HR Hormone receptor, IBR Immediate breast reconstruction, Mx Mastectomy, NA Not applicable
aPatients diagnosed with DCIS or invasive tumor in 2018/2019 or weeks 1 to 26 of 2020, excluding patients not receiving surgery for their invasive tumor
bPatients treated for their DCIS or invasive tumor in weeks 2–26 of 2018, 2019, or 2020, excluding patients not receiving surgery for their DCIS or invasive tumor. Patients can receive multiple treatments in one year and patients can receive treatment in both 2018, 2019 and 2020, and can therefore be part of multiple treatment years. For each treatment the number of patients receiving that treatment in weeks 2–26 of 2018, 2019, or 2020 are shown
cFor this variable only patients with an invasive tumor were included
dFor this variable only patients with an invasive tumor were included in group 1