Table 2.
Patients characteristics and treatment pattern in HER2-positive MBC according to HR status.
| Characteristic | HR−HER2+ | HR+HER2+ | P # | ||
|---|---|---|---|---|---|
| N = 311 | % | N = 277 | % | ||
| Median age at metastasis(y) | 53 | 50 | <0.01 | ||
| Median DRFI (IQR range) (m) | 22.9 (15.3~35.6) | 30.7 (18.5–45.9) | <0.01 | ||
| Median OS follow-up (IQR) (m) | 24.8 (14.0~40.3) | 32.5 (29.8–46.9) | <0.01 | ||
| Median No. of metastatic sites (IQR) | 2 (1–2) | 2 (1–2) | |||
| First-site of distant relapse (%) | |||||
| Visceral | 207 | 66.56 | 165 | 59.57 | 0.09 |
| Nonvisceral | 104 | 33.44 | 112 | 40.43 | |
| Brain | 13 | 4.18 | 12 | 4.33 | |
| Liver | 73 | 23.47 | 74 | 26.71 | |
| Lung | 110 | 35.37 | 68 | 24.55 | |
| Bone | 50 | 16.08 | 62 | 22.38 | |
| Other | 65 | 20.90 | 61 | 22.02 | |
| Life-time brain metastasis | 79 | 25.40 | 68 | 24.55 | 0.85 |
| Biopsy for metastatic lesions (%) | 45 | 14.47 | 39 | 14.08 | 0.99 |
| Receptor conversion | |||||
| HR+ to HR− | — | 11 | 28.21 | ||
| HR− to HR+ | 4 | 8.89 | — | ||
| HER2+ to HER2− | 4 | 8.89 | 2 | 5.13 | |
| HER2− to HER2+ | 1 | 2.22 | 1 | 2.56 | |
| Trastuzumab-naïve MBC (%) | 273 | 87.78 | 246 | 88.81 | |
| Trastuzumab-containing | 205 | 75.09 | 166 | 0.67 | 0.91 |
| first-line | 137 | 66.83 | 112 | 67.47 | |
| second-line or beyond | 68 | 33.17 | 54 | 32.53 | |
| Median duration of tratuzumab (IQR range) (m) | |||||
| 12.0 (5.3~19.6) | 16.6 (12.6~29.0) | <0.01 | |||
| First chemotherapy regimen combined with Trastuzumab* | |||||
| Taxane-based | 112 | 100 | 0.29 | ||
| Vinorelbine | 56 | 38 | |||
| Capecitabine | 48 | 34 | |||
| Hormonal therapy | — | 10 | |||
| Monotherapy | 4 | 2 | |||
| Others | 6 | 2 | |||
| Median No. of lines of palliative therapy (rang) | |||||
| 2 (1~8) | 2 (1~8) | ||||
Abbreviations: DRFI, distant recurrence-free interval, IQR, interquartile range.
*Values may add up over 100% because of triple combination was used.