Table 1.
Clinicopathological variables in metastatic breast cancer patients at baseline
| Included (136) | % | Excluded (20) | % | |
|---|---|---|---|---|
| Age, median (range) | 65 (40–90) | 65 (45–82) | ||
| < 50 | 65 | 48 | 10 | 50 |
| ≥ 50 | 71 | 52 | 10 | 50 |
| Baseline ECOG | ||||
| 0 | 75 | 57 | 16 | 90 |
| 1 | 36 | 27 | 1 | 5 |
| 2 | 21 | 16 | 1 | 5 |
| Missing | 4 | 2 | ||
| PT NHG | ||||
| I-II | 68 | 62 | 10 | 71 |
| III | 42 | 38 | 4 | 29 |
| Missing | 26 | 6 | ||
| PT tumor size | ||||
| 1 | 49 | 38 | 8 | 44 |
| 2 | 46 | 36 | 5 | 28 |
| 3 | 17 | 13 | 3 | 17 |
| 4 | 17 | 13 | 2 | 11 |
| Missing | 7 | 2 | ||
| PT node status | ||||
| negative | 39 | 33 | 5 | 28 |
| positive | 79 | 67 | 13 | 72 |
| missing | 18 | 2 | ||
| Breast cancer subtype | ||||
| ER + HER2- | 94 | 71 | 11 | 61 |
| HER2 + | 15 | 11 | 5 | 28 |
| ER- HER2- | 24 | 18 | 2 | 11 |
| Missing | 3 | 2 | ||
| Metastasis-free interval (years) | ||||
| 0 | 28 | 21 | 3 | 15 |
| > 0–3 | 25 | 18 | 3 | 15 |
| ≥ 3 | 83 | 61 | 14 | 70 |
| Missing | 0 | 0 | ||
| Metastatic sites, number | ||||
| < 3 | 96 | 71 | 13 | 65 |
| ≥ 3 | 40 | 29 | 7 | 35 |
| Missing | 0 | 0 | ||
| Site of metastasis | ||||
| Non-Visceral | 56 | 41 | 9 | 45 |
| Visceral | 80 | 59 | 11 | 55 |
| Missing | 0 | 0 | ||
| 1st line of treatment for MBC | ||||
| Endocrine | 55 | 43 | 3 | 19 |
| Chemotherapy | 60 | 47 | 11 | 69 |
| HER2-targeted | 13 | 10 | 2 | 12 |
| Missing | 8 | 4 | ||
| CTC | ||||
| < 5 | 65 | 49 | 8 | 44 |
| ≥ 5 | 69 | 51 | 10 | 56 |
| Missing | 2 | 2 | ||
| One or more CTC clusters | ||||
| No | 108 | 81 | 14 | 78 |
| Yes | 26 | 19 | 4 | 22 |
| Missing | 2 | 2 | ||
CTC circulating tumor cells; ECOG Eastern Cooperative Oncology Group; ER estrogen receptor; HER2 human epidermal growth factor; MBC metastatic breast cancer; NHG Nottingham histological grade; PT primary tumor