Table 1.
Characteristics of total patients with metastatic bone disease
| Factors | BP group N = 262 |
Non-BP group N = 55 |
P-value|| |
|---|---|---|---|
| Age, median years (range) | 45.5 (25–77) | 50 (30–68) | NS* |
| PS** (ECOG ≥ 2) | 10/166 (6.0%) | 2/27 (7.4%) | NS |
| Pre-menopausal | 79/176 (44.9%) | 7/30 (23.3%) | 0.027 |
| Post-menopausal | 97/176 (55.1%) | 23/30 (76.7%) | |
| ER***/PR† positive | 202 (77.1%) | 28 (50.9%) | < 0.001 |
| HER2 positive | 72 (27.5%) | 23 (41.8%) | 0.035 |
| DFI‡ (month, median, range) | 25 (0–230) | 21 (0–174) | NS |
| Initial stage IV | 61 (23.4%) | 11 (20%) | NS |
| Adjuvant treatment | |||
| Radiotherapy | 111 (42.4%) | 27 (49.1%) | NS |
| Chemotherapy | 176 (67.2%) | 38 (69.1%) | NS |
| Hormonal therapy | 127 (48.5%) | 21 (38.2%) | NS |
| Metastatic sites | |||
| Visceral (liver, lung) | 116 (44.3%) | 37 (67.3%) | 0.002 |
| LNs§ | 119 (45.4%) | 30 (54.5%) | NS |
| Soft tissue | 78 (29.8%) | 20 36.4%) | NS |
| Bone only | 81 (30.9%) | 8 (14.5%) | 0.014 |
| Weight bearing bone involvement | 225 (86.2%) | 25 (45.5%) | < 0.001 |
| Sum of metastatic sites (range) | 2 (1–6) | 3 (1–6) | 0.006 |
| Cycles of palliative chemotherapy | NS | ||
| 1 | 36 (13.7%) | 8 (14.5%) | |
| 2 | 53 (20.2%) | 13 (23.6%) | |
| ≥ 3 | 157 (59.9%) | 29 (52.7%) | |
| Palliative AI¶ use | 168 (64.1%) | 23 (41.8%) | 0.002 |
| Palliative anti-HER2 therapy | 58/72 (80.6%) | 20/23 (86.9%) | NS |
| Disease progression in bone (n) | 97 (47.8%) | 21 (38.2%) | NS |
| SREs (except the first event) | 63 (27.2%) | 21 (24.7%) | NS |
Abbreviations:*, not significant; **, performance status; ***, estrogen receptor; †, progesteron receptor;
‡, disease free interval; § lymph nodes; ¶ aromatase inhibitor; ||, P-value was obtained by chi-square test except variables of age and DFI which were obtained through Mann-Whitney U test