Table 2

Study cohort of patients with BC with BM (N=2427) by length of BM-free interval

Length of BM-free interval
0 to <1year
N=918
N (%)
1 to <3 years
N=686
N (%)
3 to <5 years
N=462
N (%)
≥5 years
N=361
N (%)
Overall
N=2427
N (%)
Age at BC diagnosis (years)
 25–49146 (16%)158 (23%)126 (27%)102 (28%)532 (22%)
 50–59209 (23%)187 (27%)111 (24%)110 (30%)617 (25%)
 60–69277 (30%)197 (29%)145 (31%)79 (22%)698 (29%)
 ≥70286 (31%)144 (21%)80 (17%)70 (19%)580 (24%)
Time period of BC diagnosis
 1997–2001214 (23%)215 (31%)198 (43%)247 (68%)874 (36%)
 2002–2006377 (41%)311 (45%)209 (45%)114 (32%)1011 (42%)
 2007–2011327 (36%)160 (23%)55 (12%)0 (0%)542 (22%)
Stage of disease at BC diagnosis
 Localised79 (9%)131 (19%)108 (23%)102 (28%)420 (17%)
 Regional264 (29%)426 (62%)281 (61%)233 (65%)1204 (50%)
 Metastatic491 (53%)71 (10%)38 (8%)6 (2%)606 (25%)
 Unknown84 (9%)58 (8%)35 (8%)20 (6%)197 (8%)
Hormone receptor and HER2 status
 ER-positive714 (78%)474 (69%)367 (79%)304 (84%)1859 (77%)
 ER-negative188 (20%)199 (29%)89 (19%)51 (14%)527 (22%)
 Unknown16 (2%)13 (2%)6 (1%)6 (2%)41 (2%)
 ER/PR-positive and HER2-negative233 (25%)135 (20%)84 (18%)39 (11%)491 (20%)
 HER2-positive (any ER/PR status)156 (17%)131 (19%)72 (16%)34 (9%)393 (16%)
 ER/PR-negative and HER2-negative90 (10%)91 (13%)41 (9%)16 (4%)238 (10%)
 Unknown439 (48%)329 (48%)265 (57%)272 (75%)1305 (54%)
Charlson Comorbidity Index score
 0717 (78%)521 (76%)341 (74%)283 (78%)1862 (77%)
 1–2173 (19%)141 (21%)104 (23%)67 (19%)485 (20%)
 >228 (3%)24 (4%)17 (4%)11 (3%)80 (3%)
Median age (range) at BM diagnosis64 years (28–95)62 years (28–91)63 years (29–97)65 years (36–92)63 years (28–97)
Other metastases recorded at or before BM diagnosis437 (48%)352 (51%)283 (61%)220 (61%)1292 (53%)
Skeletal-related events at BM diagnosis*
 Radiation to bone159 (17%)140 (20%)112 (24%)73 (20%)484 (20%)
 Pathological fracture10 (1%)26 (4%)14 (3%)17 (5%)67 (3%)
 Spinal cord compression13 (1%)19 (3%)18 (4%)13 (4%)63 (3%)
 Surgery to bone18 (2%)24 (4%)11 (2%)10 (3%)63 (3%)
  • *Categories not mutually exclusive.

  • BC, breast cancer; BM, bone metastasis; ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; PR, progesterone receptor.