Who Needs Extended Endocrine Therapy for HR+ Breast Cancer?

For patients with hormone receptor–positive (HR+) breast cancer, the recommended duration of adjuvant endocrine therapy ranges from 5 to 10 years. For many patients, the notion of continuing treatment beyond 5 years is distressing due to the adverse effects, but for others the idea of stopping at 5 years is equally distressing due to concerns regarding disease recurrence. To decide whether to recommend continuing treatment beyond 5 years, physicians often use their “gestalt” of the clinical characteristics of a tumor partnered with their assessment of the psyche of an individual patient. In this era, that question relates largely to longer durations of aromatase inhibitor (AI) treatment, and several molecular tools have been purported to ai…