Table 1.
Baseline demographic and clinical characteristics of younger (<65 years), older (65–74 years), and elderly (≥75 years) patients at diagnosis of MBC
| Variable, n (%) | Age (years) at MBC | ||
|---|---|---|---|
| <65 (n = 792) | 65–74 (n = 144) | ≥75 (n = 65) | |
| Age at enrollment (years), median (range) | 50 (20–65) | 69 (65–75) | 79 (75–92) |
| Race/ethnicity | |||
| White | 614 (77.5) | 123 (85.4) | 56 (86.2) |
| Black | 106 (13.4) | 14 (9.7) | 6 (9.2) |
| Other | 72 (9.1) | 7 (4.9) | 3 (4.6) |
| BMI, kg/m2 | |||
| <30 | 506 (63.9) | 91 (63.2) | 53 (81.5) |
| ≥30 | 286 (36.1) | 53 (36.8) | 12 (18.5) |
| ECOG performance status at diagnosis | |||
| 0–1 | 361 (45.6) | 69 (47.9) | 25 (38.5) |
| 2+ | 44 (5.6) | 11 (7.6) | 5 (7.7) |
| Unknown/missing | 387 (48.9) | 64 (44.4) | 35 (53.8) |
| Site of metastatic disease at diagnosis | |||
| Any CNS | 63 (8.0) | 8 (5.6) | 1 (1.5) |
| Bone only or bone + breast | 118 (14.9) | 18 (12.5) | 12 (18.5) |
| Visceral | 478 (60.4) | 92 (63.9) | 37 (56.9) |
| Node/local | 131 (16.5) | 26 (18.1) | 15 (23.1) |
| Other sites | 2 (0.3) | 0 (0) | 0 (0) |
| Clinical stage at initial diagnosis | |||
| Stage I–III, MBC ≤12 months after initial diagnosis | 108 (13.6) | 23 (16.0) | 4 (6.2) |
| Stage I–III, MBC >12 months after initial diagnosis | 457 (57.7) | 88 (61.1) | 47 (72.3) |
| Stage IV | 227 (28.7) | 33 (22.9) | 14 (21.5) |
| ER/PR status | |||
| ER+ or PR+ | 426 (53.8) | 71 (49.3) | 33 (50.8) |
| ER− and PR− | 341 (43.1) | 63 (43.8) | 30 (46.2) |
| Unknown | 25 (3.2) | 10 (6.9) | 2 (3.1) |
| History of diabetes | 46 (5.9) | 21 (14.6) | 11 (16.9) |
| History of underlying CVDa | 100 (12.6) | 42 (29.2) | 30 (46.2) |
| Arrhythmia | 7 (0.9) | 7 (4.9) | 8 (12.3) |
| Congestive heart failure | 6 (0.8) | 3 (2.1) | 6 (9.2) |
| Hypertension with complications | 21 (2.7) | 18 (12.5) | 9 (13.8) |
| Angina | 2 (0.3) | 0 (0.0) | 1 (1.5) |
| Myocardial infarction | 9 (1.1) | 5 (3.5) | 5 (7.7) |
| Peripheral vascular disease | 8 (1.0) | 3 (2.1) | 2 (3.1) |
| Other underlying cardiac disease | 61 (7.7) | 21 (14.6) | 17 (26.2) |
BMI body mass index, CNS central nervous system, CVD cardiovascular disease, MBC metastatic breast cancer, ECOG Eastern Cooperative Oncology Group, ER estrogen receptor, PR progesterone receptor
aPatients could be counted in multiple CVD categories