Table 1.
Cause-specific deaths by treatment arm and factor subgroups*
| Factor | No. of patients (%) |
Breast cancer deaths, No. |
Deaths from other malignancies, No. |
Deaths from other causes, No. |
||||
|---|---|---|---|---|---|---|---|---|
| Letrozole (n = 2583) |
Placebo (n = 2587) |
Letrozole | Placebo | Letrozole | Placebo | Letrozole | Placebo | |
| Age | ||||||||
| < 70 y | 1901 (73.6) | 1946 (75.2) | 31 | 37 | 12 | 14 | 19 | 17 |
| ≥70 y | 682 (26.4) | 641 (24.8) | 15 | 19 | 13 | 11 | 36 | 28 |
| Menopausal status† | ||||||||
| < 50 y + missing | 618 (23.9) | 626 (24.2) | 4 | 12 | 1 | 1 | 2 | 1 |
| ≥50 y | 1965 (76.1) | 1961 (75.8) | 42 | 44 | 24 | 24 | 53 | 44 |
| Tamoxifen treatment | ||||||||
| ≤5 y + missing | 1162 (45.0) | 1213 (46.9) | 25 | 25 | 15 | 7 | 30 | 19 |
| > 5 y | 1421 (55.0) | 1374 (53.1) | 21 | 31 | 10 | 18 | 25 | 26 |
| Radiation therapy | ||||||||
| No + missing | 1023 (39.6) | 1054 (40.7) | 13 | 25 | 11 | 9 | 25 | 27 |
| Yes | 1560 (60.4) | 1533 (59.3) | 33 | 31 | 14 | 16 | 30 | 18 |
| Bone fracture | ||||||||
| No + missing | 2295 (88.9) | 2281 (88.2) | 40 | 50 | 24 | 22 | 46 | 39 |
| Yes | 288 (11.1) | 306 (11.8) | 6 | 6 | 1 | 3 | 9 | 6 |
| Osteoporosis | ||||||||
| No + missing | 2273 (88.0) | 2280 (88.1) | 43 | 53 | 21 | 19 | 47 | 39 |
| Yes | 310 (12.0) | 307 (11.9) | 3 | 3 | 4 | 6 | 8 | 6 |
| Cardiovascular disease | ||||||||
| No + missing | 2268 (87.8) | 2294 (88.7) | 41 | 50 | 23 | 20 | 33 | 35 |
| Yes | 315 (12.2) | 293 (11.3) | 5 | 6 | 2 | 5 | 22 | 10 |
| Hormone receptor status | ||||||||
| Unknown | 55 (2.1) | 56 (2.2) | 2 | 2 | 2 | 1 | 2 | 0 |
| Positive | 2528 (97.9) | 2531 (97.8) | 44 | 54 | 23 | 24 | 53 | 45 |
| Lymph node status | ||||||||
| Negative | 1299 (50.3) | 1301 (50.3) | 9 | 9 | 14 | 11 | 24 | 17 |
| Unknown | 100 (3.9) | 98 (3.8) | 5 | 2 | 2 | 1 | 6 | 2 |
| Positive | 1184 (45.8) | 1188 (45.9) | 32 | 45 | 9 | 13 | 25 | 26 |
| Adjuvant chemotherapy | ||||||||
| No | 1385 (53.6) | 1388 (53.7) | 22 | 27 | 20 | 17 | 37 | 30 |
| Yes | 1198 (46.4) | 1199 (46.3) | 24 | 29 | 5 | 8 | 18 | 15 |
Four patients had a missing cause of death and are not included above. Deaths from other malignancies were as follows: 12 from lung cancer (11 from non—small cell lung cancer and one from small-cell lung cancer), eight from pancreatic cancer, five from colorectal cancer (four from colon cancer and one from rectal cancer), four from endometrial cancer, four from non-Hodgkin lymphoma, three from esophageal cancer, four from ovary or peritoneal cancer, two from head and neck cancer, two from sarcoma, one from leukemia, one from myelodysplastic disease, two from biliary tract cancer, one from melanoma, and one from an unknown type of cancer. Deaths from other causes were as follows: 39 from cardiovascular disease including stroke, 11 from organ failure other than cardiovascular disease, 12 from causes not otherwise specified (one possibly with unconfirmed pancreatic cancer), four from neurological disease, 14 from infection, six from hemorrhage, two from trauma, and 12 from multiple causes.
Menopausal status was defined in terms of a cut point at 50 years of age; those at least 50 years of age were considered to be postmenopausal.