Table 2.
Summary of adjuvant trials comparing aromatase inhibitors to tamoxifen for upfront, sequential, and extended use
| Trial | Agent | No. of patients
|
DFS/EFS
|
OS
|
Median follow up | ||||
|---|---|---|---|---|---|---|---|---|---|
| AI/sequential | Control | HR | P | HR | P | ||||
| Upfront use trials (AI vs TAM) | ATAC30 BIG 1–9831 |
ANA LET |
3125 2463 |
3166 2459 |
0.91 0.88 |
0.04 0.03 |
0.95 0.87 |
0.4 0.08 |
120 mo 76 mo |
| Sequential use trials (TAM → AI vs TAM) | ARNO 9539 ABCSG-837 ITA38 IES35 |
ANA ANA ANA EXE |
489 (ITT) 1865 (ITT) 223 2352 |
490 (ITT) 1845 (ITT) 225 2372 |
0.66 0.82 0.57 0.76 |
0.049 0.038 0.005 0.0001 |
0.53 0.78* 0.57 0.83† |
0.045 0.032 0.1 0.05 |
30.1 mo 72 mo 64 mo 55.7 mo |
| Planned sequential trials (TAM → AI vs AI) | TEAM40 BIG 1–9831 |
TAM → EXE LET → TAM TAM → LET |
4868 1540 1548 |
4898 1546 1546 |
0.97 0.96 1.05 |
0.6 NS NS |
1 0.9 1.13 |
>0.9 NS NS |
60 mo 71 mo 71 mo |
| Extended use trials (AI after completing TAM vs Placebo) | MA-1741 NSABP-B3343 |
LET EXE |
2593 783 |
2594 779 |
0.58 0.68 |
<0.001 0.07 |
– 0.82 |
NS 0.3 |
30 mo 30 mo |
Notes:
Crossover censored;
122 estrogen receptor negative patients were sensored.
Abbreviations: DFS, disease free survial; EFS, event free survival; OS, overall survival; AI, aromatase inhibitor; HR, hazard ratio; ATAC, Arimidex, Tamoxifen, Alone or in Combination (trial); ANA, anastrozole; TAM, tamoxifen; BIG, Breast International Group; LET, letrozole; ARNO, Arimidex-Nolvadex (trial); ABCSG, Austrian Breast and Colorectal Cancer Study Group; ITA, Italian Tamoxifen Anastrozole (trial); IES, Intergroup Exemestane Study; EXE, exemestane; TEAM, Tamoxifen Exemestane Adjuvant Multinational (trial); NSABP, National Surgical Adjuvant Breast and Bowel Project; mo, month.