Table 2.
Unweighted baseline characteristics of the third-line treatment study population.
| T-DXd n = 1825 |
Tucatinib n = 566 |
All n = 2391 |
|
|---|---|---|---|
| Year of inclusion | |||
| 2020 | 172 (9⋅4) | 1 (0⋅2) | 173 (7⋅2) |
| 2021 | 711 (39⋅0) | 338 (59⋅7) | 1049 (43⋅9) |
| 2022 | 590 (32⋅3) | 167 (29⋅5) | 757 (31⋅7) |
| 2023 | 352 (19⋅3) | 60 (10⋅6) | 412 (17⋅2) |
| Mean age (SD), years | 60⋅2 (12⋅8) | 58⋅2 (12⋅0) | 59⋅7 (12⋅6) |
| Median age (IQR), years | 60⋅0 (51⋅0–69⋅0) | 59⋅0 (50⋅0–67⋅0) | 59⋅0 (51⋅0–69⋅0) |
| Age categories, years | |||
| 18–49 | 370 (20⋅3) | 141 (24⋅9) | 511 (21⋅4) |
| 50–59 | 535 (29⋅3) | 156 (27⋅6) | 691 (28⋅9) |
| 60–69 | 464 (25⋅4) | 169 (29⋅9) | 633 (26⋅5) |
| ≥70 | 456 (25⋅0) | 100 (17⋅7) | 556 (23⋅3) |
| Sex: female | 1803 (98⋅8) | 564 (99⋅6) | 2367 (99⋅0) |
| Deprivation index, quintiles | |||
| 1 (least deprived) | 337 (18⋅5) | 121 (21⋅4) | 458 (19⋅2) |
| 2 | 318 (17⋅4) | 121 (21⋅4) | 439 (18⋅4) |
| 3 | 354 (19⋅4) | 117 (20⋅7) | 471 (19⋅7) |
| 4 | 367 (20⋅1) | 91 (16⋅1) | 458 (19⋅2) |
| 5 (most deprived) | 374 (20⋅5) | 102 (18⋅0) | 476 (19⋅9) |
| 0 (not estimated) | 46 (2⋅5) | 10 (1⋅8) | 56 (2⋅3) |
| Missing | 29 (1⋅6) | 4 (0⋅7) | 33 (1⋅4) |
| Duration of breast cancer | |||
| ≤3 years | 466 (25⋅5) | 149 (26⋅3) | 615 (25⋅7) |
| 3–8 years | 864 (47⋅3) | 288 (50⋅9) | 1152 (48⋅2) |
| >8 years | 495 (27⋅1) | 129 (22⋅8) | 624 (26⋅1) |
| Local or unspecific treatments (past 5 years) | |||
| Breast surgery | 1011 (55⋅4) | 360 (63⋅6) | 1371 (57⋅3) |
| Radiotherapy | 1267 (69⋅4) | 461 (81⋅4) | 1728 (72⋅3) |
| IV chemotherapy | 858 (47⋅0) | 251 (44⋅3) | 1109 (46⋅4) |
| Per os chemotherapy | 616 (33⋅8) | 349 (61⋅7) | 965 (40⋅4) |
| Endocrine therapy | 1154 (63⋅2) | 312 (55⋅1) | 1466 (61⋅3) |
| HER2 targeting therapy (past 5 years) | |||
| Pertuzumab | 1420 (77⋅8) | 452 (79⋅9) | 1872 (78⋅3) |
| Trastuzumab alone | 1125 (61⋅6) | 426 (75⋅3) | 1551 (64⋅9) |
| Lapatinib | 302 (16⋅5) | 79 (14⋅0) | 381 (15⋅9) |
| Metastases | 1565 (85⋅8) | 514 (90⋅8) | 2079 (87⋅0) |
| Lymph node | 518 (28⋅4) | 170 (30⋅0) | 688 (28⋅8) |
| Bone | 1025 (56⋅2) | 316 (55⋅8) | 1341 (56⋅1) |
| Digestive | 651 (35⋅7) | 231 (40⋅8) | 882 (36⋅9) |
| Pulmonary | 647 (35⋅5) | 193 (34⋅1) | 840 (35⋅1) |
| Brain | 534 (29⋅3) | 323 (57⋅1) | 857 (35⋅8) |
| Duration of metastatic disease | |||
| ≤1 year | 226 (12⋅4) | 63 (11⋅1) | 289 (12⋅1) |
| 1–4 years | 894 (49⋅0) | 313 (55⋅3) | 1207 (50⋅5) |
| >4 years | 445 (24⋅4) | 138 (24⋅4) | 583 (24⋅4) |
| No active metastases | 260 (14⋅2) | 52 (9⋅2) | 312 (13⋅0) |
| Comorbid condition | 790 (43⋅3) | 260 (45⋅9) | 1050 (43⋅9) |
| Cardiac | 248 (13⋅6) | 76 (13⋅4) | 324 (13⋅6) |
| Diabetes | 163 (8⋅9) | 48 (8⋅5) | 211 (8⋅8) |
| Respiratory | 121 (6⋅6) | 37 (6⋅5) | 158 (6⋅6) |
| Neurologic | 82 (4⋅5) | 39 (6⋅9) | 121 (5⋅1) |
| Psychiatric | 87 (4⋅8) | 36 (6⋅4) | 123 (5⋅1) |
| IMID | 45 (2⋅5) | 13 (2⋅3) | 58 (2⋅4) |
| Liver/pancreas | 82 (4⋅5) | 15 (2⋅7) | 97 (4⋅1) |
| Obesity | 174 (9⋅5) | 49 (8⋅7) | 223 (9⋅3) |
| Tobacco use | 174 (9⋅5) | 71 (12⋅5) | 245 (10⋅2) |
Figures are presented in numbers (percentages), unless stated otherwise.
T-DM1: trastuzumab emtansine; T-DXd: trastuzumab deruxtecan; SD: standard deviation; IQR: interquartile range; HER2: human epidermal growth factor receptor 2; IV: intravenous; IMID: immune-mediated inflammatory disease (including rheumatoid arthritis, spondyloarthritis, and inflammatory bowel diseases).