Table 1.
Patient demographics and baseline disease characteristics
| Characteristics | Placebo group (n = 195) |
|---|---|
| Age, mean years ± SD | 56 ± 12 |
| Patients < 50 years of age, n (%) | 67 (34) |
| ECOG performance status, n (%) | |
| 0 – 1 | 128 (66) |
| 2 – 3 | 67 (34) |
| Estrogen- and progesterone-receptor status, n (%) | |
| Positive for at least 1 | 120 (62) |
| Other | 75 (38) |
| Sites of metastasis, patients, n (%) | |
| Bone, any | 195 (100) |
| Bone as only metastatic site | 117 (60) |
| Lung | 30 (15) |
| Liver | 29 (15) |
| Brain | 1 (1) |
| Other | 27 (14) |
| Time from primary to bone metastases diagnosis, median years ± SD | 3.8 ± 4.5 |
| Time from bone metastases to study entry, mean years ± SD | 1.6 ± 1.7 |
| Patients with bone lesions ≥ 1 cm in diameter, n (%) | |
| 1 lesion | 82 (42) |
| 2 lesions | 71 (36) |
| ≥ 3 lesions | 42 (22) |
| Lesion types and numbers | |
| 1 – 2 osteolytic | 104 (53) |
| ≥ 3 osteolytic | 91 (47) |
| 0 osteoblastic | 146 (75) |
| 1 – 2 osteoblastic | 37 (19) |
| ≥ 3 osteoblastic | 12 (6) |
| 0 mixed lesions | 28 (14) |
| 1 – 2 mixed lesions ≥ 3 mixed lesions |
61 (31) 106 (54) |
| Patients with SREs during the 3 months before study entry, n (%) | |
| Palliative radiotherapy | 57 (29) |
| Fracture | 35 (18) |
| Pain scores, n (%) | |
| 0 | 27 (14) |
| 1 – 3 | 76 (39) |
| 4 – 9 | 92 (47) |
| Prior therapy regimens, n (%) | |
| 0 – 1 chemotherapy | 80 (41) |
| 2 – 3 chemotherapy | 104 (53) |
| ≥ 4 chemotherapy | 11 (6) |
| 0 – 1 hormonal therapy | 102 (52) |
| 2 – 3 hormonal therapy | 77 (39) |
| ≥ 4 hormonal therapy | 16 (8) |
SD = Standard deviation, ECOG = Eastern Cooperative Oncology Group, SRE = Skeletal-related event.
Adapted with permission from Hortobagyi et al. Efficacy of pamidronate in reducing skeletal complications in patients with breast cancer and lytic bone metastases. Protocol 19 Aredia Breast Cancer Study Group. N Engl J Med. 1996;335:1785–1791. Copyright© 1996 Massachusetts Medical Society. All rights reserved[15]