Table 1. Patient Characteristics.
| Characteristic | No. (%) | P value | ||
|---|---|---|---|---|
| Overall population (N = 745) | Abiraterone acetate cohort (n = 529) | BRI cohort (n = 216) | ||
| Age at baseline, median (IQR), y | 77.6 (68.1-83.6) | 78.3 (70.5-85.4) | 75.8 (66.9-81.2) | .10 |
| Race | ||||
| White | 699 (93.8) | 497 (94.0) | 202 (93.5) | .08 |
| Othera | 19 (2.6) | 10 (1.9) | 9 (4.2) | |
| Not available | 27 (3.6) | 22 (4.2) | 5 (2.3) | |
| Gleason score | ||||
| ≤6 | 62 (8.3) | 42 (7.9) | 20 (9.3) | .53 |
| 7 | 218 (29.3) | 145 (27.4) | 73 (33.8) | |
| ≥8 | 337 (45.2) | 234 (44.2) | 103 (47.7) | |
| Not available | 128 (17.2) | 108 (20.4) | 20 (9.3) | |
| Previous local therapy | ||||
| No | 353 (47.4) | 265 (50.1) | 88 (40.7) | .03 |
| Surgery | 196 (26.3) | 127 (24.0) | 69 (31.9) | |
| Radiotherapy | 181 (24.3) | 125 (23.6) | 56 (25.9) | |
| Not available | 15 (2.0) | 12 (2.3) | 3 (1.4) | |
| De novo | ||||
| No | 483 (64.8) | 340 (64.3) | 143 (66.2) | .64 |
| Yes | 262 (35.2) | 189 (35.7) | 73 (33.8) | |
| Treatment for mHSPC | ||||
| ADT | 617 (82.8) | 475 (89.8) | 142 (65.7) | <.001 |
| ADT plus docetaxel | 81 (10.9) | 41 (7.8) | 40 (18.5) | |
| Not available | 47 (6.3) | 13 (2.5) | 34 (15.7) | |
| Volume of disease at baselineb | ||||
| Low | 276 (37.0) | 179 (33.8) | 97 (44.9) | <.001 |
| High | 420 (56.4) | 336 (63.5) | 84 (38.9) | |
| Not available | 49 (6.6) | 14 (2.6) | 35 (16.2) | |
| Visceral metastases at baseline | ||||
| No | 680 (91.3) | 477 (90.2) | 203 (94.0) | .09 |
| Yes | 65 (8.7) | 52 (9.8) | 13 (6.0) | |
| Liver metastases at baseline | ||||
| No | 709 (95.2) | 506 (95.7) | 203 (94.0) | .33 |
| Yes | 36 (4.8) | 23 (4.3) | 13 (6.0) | |
| ECOG performance status at baseline | ||||
| 0 | 324 (43.5) | 224 (42.3) | 100 (46.3) | .01 |
| ≥1 | 369 (49.5) | 287 (54.3) | 82 (38.0) | |
| Not available | 52 (7.0) | 18 (3.4) | 34 (15.7) | |
| Pain intensity at baseline, VAS | ||||
| 0-3 | 514 (69.0) | 389 (73.5) | 125 (57.9) | .03 |
| 4-5 | 112 (15.0) | 71 (13.4) | 41 (19.0) | |
| >5 | 70 (9.4) | 53 (10.0) | 17 (7.9) | |
| Not available | 49 (6.6) | 16 (3.0) | 33 (15.3) | |
| Receiving opioids at baseline | ||||
| No | 598 (80.3) | 449 (84.9) | 149 (69.0) | .05 |
| Yes | 99 (13.3) | 65 (12.3) | 34 (15.7) | |
| Not available | 48 (6.4) | 15 (2.8) | 33 (15.3) | |
| PSA at baseline, median (IQR), ng/mL | 32 (10.0-98.5) | 37.5 (12.2-126.2) | 19.3 (6.4-57.0) | .18 |
| Receiving a BRI | ||||
| No | 529 (71.0) | 529 (100) | 0 | NA |
| Zoledronic acid | 84 (11.3) | 0 | 84 (38.9) | |
| Denosumab | 132 (17.7) | 0 | 132 (61.1) | |
| Time from start of abiraterone acetate with prednisone to start of BRI, median (IQR), d | 15 (0-68) | NA | 15 (0-68) | NA |
| Duration of BRI receipt, median (IQR), d | 741 (362-1182) | NA | 741 (362-1182) | NA |
| No. of abiraterone acetate with prednisone cycles, median (IQR) | 9 (4-20) | 10 (4-21) | 7 (4-14) | .01 |
| Receiving pain palliation | ||||
| No | 198 (26.6) | 127 (24.0) | 71 (32.9) | .002 |
| Yes | 497 (66.7) | 386 (73.0) | 111 (51.4) | |
| Not available | 50 (6.7) | 16 (3.0) | 34 (15.7) | |
| No. of treatments received after abiraterone acetate with prednisone | ||||
| Median (IQR) | 1 (0-2) | 0 (0-1) | 2 (1-3) | <.001 |
| 0-1 | 511 (68.6) | 417 (78.8) | 94 (43.5) | |
| >1 | 225 (30.2) | 112 (21.2) | 113 (52.3) | |
| Not available | 9 (1.2) | 0 | 9 (4.2) | |
| Follow-up in overall population, median (95% CI), mo | 23.5 (19.8-24.9) | 21.6 (17.2-25.3) | 28.6 (22.5-34.3) | .36 |
Abbreviations: ADT, androgen deprivation therapy; BRI, bone resorption inhibitor; ECOG, Eastern Cooperative Oncology Group; IQR, interquartile range; mHSPC, metastatic hormone-sensitive prostate cancer; NA, not available/not applicable; PSA, prostate-specific antigen; VAS, visual analog scale.
a
Races included in this category were not specifically identified.
b
High-volume disease was defined as visceral metastases and/or at least 4 bone metastases, including 1 or more metastases out of the axis and pelvis. Low-volume disease was defined as the absence of high-volume disease.