Table 2.
Baseline demographics and clinical characteristics,a stratified by ILD status
| No ILD (N = 384) | Prevalent ILD (N = 84) | Incident ILD (N = 65) | Total (N = 533) | |
|---|---|---|---|---|
| Age at initial breast cancer diagnosis [median (IQR)] | 53 (44, 62) | 58 (46, 66) | 54 (45, 62) | 53 (45, 63) |
| Age at metastatic diagnosis [median (IQR)] | 56 (47, 64) | 61 (52, 69) | 57 (48, 64) | 57 (48, 65) |
| Race [n (%)] | ||||
| White | 298 (78) | 64 (76) | 48 (74) | 410 (77) |
| Black or African-American | 67 (17) | 14 (17) | 17 (26) | 98 (18) |
| Asian | 11 (3) | 3 (3.5) | 0 (0) | 14 (3) |
| Other or not provided | 8 (2) | 3 (3.5) | 0 (0) | 11 (2) |
| Ethnicity | ||||
| Hispanic/Latino | 22 (6) | 4 (5) | 1 (2) | 27 (5) |
| Non-Hispanic/Non-Latino | 357 (93) | 76 (90) | 62 (95) | 495 (77) |
| Not provided | 5 (1) | 4 (5) | 2 (3) | 11 (2) |
| Stage IV at diagnosis [n (%)] | 193 (50) | 39 (46) | 38 (58) | 270 (51) |
| ECOG at metastatic diagnosis [n (%)] | ||||
| 0 | 68 (18) | 19 (23) | 12 (18) | 99 (19) |
| 1 | 61 (16) | 16 (19) | 7 (11) | 84 (16) |
| 2+ | 26 (7) | 8 (9) | 5 (8) | 39 (7) |
| Unknown | 229 (60) | 41 (49) | 41 (63) | 311 (58) |
| BMI | ||||
| Normal | 95 (25) | 24 (29) | 19 (29) | 138 (26) |
| Overweight | 102 (27) | 22 (26) | 10 (15) | 134 (25) |
| Obese | 118 (31) | 31 (37) | 21 (32) | 170 (32) |
| Unknown | 69 (18) | 7 (8) | 15 (23) | 91 (17) |
| Menopausal status at metastatic diagnosis | ||||
| Premenopausal | 91 (24) | 10 (12) | 16 (25) | 117 (22) |
| Perimenopausal | 8 (2) | 1 (1) | 1 (2) | 10 (2) |
| Postmenopausal | 240 (62) | 65 (77) | 36 (55) | 341 (64) |
| Unknown/not available | 45 (12) | 8 (9) | 12 (18) | 65 (12) |
| Smoking history at initial diagnosis (ever smoked) | 157 (41) | 37 (44) | 34 (52) | 228 (43) |
| Thoracic radiationb | 35 (9) | 8 (10) | 6 (9) | 49 (9) |
| Lung metastasis | 98 (26) | 37 (44) | 23 (35) | 158 (30) |
| COPD | 14 (4) | 9 (11) | 7 (11) | 30 (6) |
| Pulmonary embolism | 5 (1) | 5 (6) | 0 (0) | 10 (2) |
| Lung cancer | 1 (0) | 2 (2) | 0 (0) | 3 (1) |
| Anemia | 93 (24) | 33 (39) | 13 (20) | 139 (26) |
| Autoimmune conditionc | 12 (3) | 4 (5) | 2 (3) | 18 (3) |
BMI Body mass index, COPD chronic obstructive pulmonary disease, ECOG Eastern Collaborative Oncology Group, ILD interstitial lung disease, IQR interquartile range, n: number
aAssessed at index date unless otherwise specified
bDefinitive, palliative or prophylactic radiation to lungs, mediastinal, and chest wall for lung metastasis from breast cancer, lung cancer, or treatment that included lung in the therapy field. Does not include radiation received to the intact breast
cLupus, rheumatoid arthritis, sarcoidosis, scleroderma, and/or polymyositis/dermatomyositis