Deescalation of Endocrine Therapy Duration in Women With HR+ HER2- Breast Cancer at Very Low Risk

Hormone therapy is recommended for five years in all patients with hormone receptor-positive breast cancer, but there is no consensus on its duration in low-risk tumours and especially in postmenopausal women. Adjuvant endocrine therapy (ET) is associated with substantial side effects and long-term decreased quality of life.

Moreover, while it has been shown that ET provides a real benefit in reducing the relapse rate over time, the deterioration in quality of life may also have a negative effect on patient adherence to treatment. It is therefore important to offer treatment to women with low-risk cancer less intensive treatment strategies. If recent trials tested longer durations as compared to 5 years for high-risk cancers, older trials have tested shorter durations. The 5-year duration appeared at that time as the gold standard because of optimal benefit-risk ratios of tamoxifen among high-risk patients. However shorter treatments of 2-3 years were already associated with substantial benefits and may be enough for very low risk patients.