- Incorporating 2 years of ovarian function suppression (OFS) with the standard 5-year regimen of tamoxifen is associated with extended DFS in women with stage I-III estrogen receptor-positive breast cancer who remain in a premenopausal state or resume ovarian function after chemotherapy and definitive surgery.
Why this matters
- Study confirms the benefits of OFS, but for a shorter duration than the 5-year SOFT and TEXT trials.
- Multicenter randomized controlled ASTRRA trial of 1293 Korean women receiving 20 mg/day tamoxifen for 5 years, with or without 2 years of OFS (3.6 mg subcutaneous goserelin every 28 days) after definitive surgery and adjuvant or neoadjuvant chemotherapy.
- Women had to remain premenopausal or resume ovarian function after chemotherapy before randomization; women who had permanent chemotherapy-induced amenorrhea were excluded from the survival analysis.
- Funding: AstraZeneca; Korea Institute of Radiological and Medical Sciences.
- At a median follow-up of 63 months, OFS plus tamoxifen yielded superior 5-year estimated DFS vs tamoxifen alone (91.1% vs 87.5%; HR, 0.69, P=.033).
- Add-on OFS also significantly extended 5-year estimated OS (99.4% vs 97.8%; HR, 0.31, P=.029).
- Open-label design.