Table 1.
Clinical characteristics of HER2-positive breast cancers with brain metastasis.
| Characteristics | No. (%) (n = 35) |
|---|---|
| Age | |
| Median (range), years | 47 (25–67) |
| <50 | 19 (54.3) |
| ≥50 | 16 (45.7) |
| The confirmed time, years | 5.1 (1–15) |
| ECOG scale | |
| 0–1 | 22 (62.9) |
| ≥2 | 13 (37.1) |
| Primary tumor laterality | |
| Left | 18 (51.4) |
| Right | 16 (45.7) |
| Bilateral | 1 (2.9) |
| Histology | |
| IDC | 34 (97.1) |
| Other | 1 (2.9) |
| Grade | |
| II | 9 (25.7) |
| III | 16 (45.7) |
| Unknown | 10 (28.6) |
| HR status | |
| Positive | 19 (54.3) |
| Negative | 16 (45.7) |
| HER2 heterogeneity | |
| No | 15 (42.9) |
| Yes | 4 (11.4) |
| Unknown | 16 (45.7) |
| T | |
| T1 | 4 (11.4) |
| T2 | 24 (68.6) |
| T3 | 2 (5.7) |
| T4 | 3 (8.6) |
| Tx | 2 (5.7) |
| N | |
| N0 | 6 (17.1) |
| N1 | 16 (45.7) |
| N2 | 7 (20) |
| N3 | 6 (17.1) |
| Nx | |
| Stage at diagnosis | |
| I | 3 (8.6) |
| II | 12 (34.3) |
| III | 11 (31.4) |
| IV | 7 (20.0) |
| Unknown | 2 (5.7) |
| No. of extracranial metastasis | |
| 0 | 4 (11.4) |
| 1 | 13 (37.1) |
| ≥2 | 18 (51.4) |
| Extracranial metastasis sites | |
| Lymph nodes and/or soft tissue | 16 (45.7) |
| Bone | 19 (54.3) |
| Lung | 20 (57.1) |
| Liver | 14 (40.0) |
| No. of visceral metastases (including brain) | |
| 1 | 10 (28.6) |
| 2 | 15 (42.9) |
| ≥3 | 10 (28.6) |
| No. of brain metastases | |
| <3 | 13 (37.1) |
| ≥3 | 17 (48.6) |
| Unknown | 5 (14.3) |
| Location of brain metastases | |
| Brain parenchyma metastases only | 31 (88.6) |
| Subtentorial only | 6 (17.1) |
| Supratentorial only | 11 (31.4) |
| Supratentorial and subtentorial | 12 (34.3) |
| Brain parenchyma and meningeal metastases | 2 (5.7) |
| Supratentorial and subtentorial | 2 (5.7) |
| Meningeal metastases only | 1 (2.9) |
| Unknown | 1 (2.9) |
| Symptoms of brain metastases | |
| Yes | 14 (40.0) |
| No | 18 (51.4) |
| Unknown | 3 (8.6) |
| Resistance to prior trastuzumab | |
| Sensitive | 6 (17.1) |
| Primary resistance | 7 (20.0) |
| Acquired resistance | 22 (62.9) |
| Prior brain radiotherapy | |
| Yes | 13 (37.1) |
| No | 22 (62.9) |
| Prior HER2-targeted therapy | |
| Trastuzumab | 35 (100) |
| Pertuzumab | 8 (22.9) |
| TKIs | 10 (28.6) |
| T-DM1 | 1 (2.9) |
| Patient’s vital status | |
| Alive | 22 (62.9) |
| Deceased | 13 (37.1) |
| Total | 35 (100.0) |
Values are presented as number (%). Visceral metastases referred to lung, liver, brain, pleural, and peritoneal involvement. HER2 heterogeneity: the HER2 status of the primary and metastatic lesions was inconsistent.
ECOG, Eastern Cooperative Oncology Group; HER2, human epidermal growth factor receptor 2; HR, hormone receptor; IDC, infiltrating ductal carcinoma; T-DM1, ado-trastuzumab emtansine; TKIs, tyrosine kinase inhibitors.