Table 1.
Aromatase Inhibitor Trials of Early Breast Cancer Treatment
| Trial | AI | Duration (months) | N | Disease-free survival (Hazard Ratio, 95% CI) |
|---|---|---|---|---|
| Concurrent trials (tamoxifen vs. AI) | ||||
| ATAC6 | Anastrozole | 30.7 | 9366 | Stopped due to lack of benefit |
| Head to head trials (tamoxifen vs AI) | ||||
| ATAC6 | Anastrozole | 47 | 6241 | 0.86 (0.76–0.99) |
| BIG 1–9813 | Letrozole | 41 | 8028 | 0.82 (0.71–0.95) |
| Switch trials (tamoxifen for 5 years vs. tamoxifen for 2–3 years followed by AI for 2–3 years) | ||||
| Meta-analysis12 | Anastrozole | 30 | 4006 | 0.59(0.48–0.74) |
| IES7 | Exemestane | 30.6 | 4724 | 0.67(0.56–0.82) |
| Extended adjuvant trials (tamoxifen for 5 years followed by AI for 5 years vs. placebo for 5 years) | ||||
| NCIC CTG MA.178 | Letrozole | 5187 | 0.58(0.45–0.76) | |
| NSABP15 | Exemestane | 1598 | 1.20 (0.57–2.52) | |
aromatase inhibitor, Arimidex, Tamoxifen Alone or in Combination trial, Breast International Group 1-98 trial, Intergroup Exemestane Study, National Cancer Institute of Canada Clinical Trials Group, National Surgical Adjuvant Breast and Bowel Project B-33 trial.