The BIG 1-98 trial evaluated adjuvant endocrine therapy strategies in postmenopausal hormone receptor-positive early breast cancer. Its primary comparison was:
- A 10 years of tamoxifen versus 5 years of tamoxifen
- B 5 years of letrozole versus 5 years of tamoxifen as monotherapy adjuvant treatment ✓
- C Anastrozole versus tamoxifen for 5 years (same design as ATAC)
- D Sequential switching from tamoxifen to exemestane versus continuous tamoxifen
Explanation
The BIG 1-98 (Breast International Group) trial compared 5 years of letrozole (aromatase inhibitor) versus 5 years of tamoxifen as monotherapy adjuvant treatment in postmenopausal ER+ early breast cancer. Letrozole significantly improved disease-free survival (hazard ratio ~0.82) over tamoxifen monotherapy at 5 years. The trial also had sequential switch arms (tamoxifen then letrozole, or letrozole then tamoxifen). This complements the ATAC trial findings for anastrozole and contributed to establishing aromatase inhibitors as preferred adjuvant therapy in postmenopausal women.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.