To the Editor The article by Yu et al1 is fascinating and important. They describe the hazard rates for distant recurrence in the 25-year period following a diagnosis of estrogen receptor–positive breast cancer. Patients were subdivided into whether they received tamoxifen or no endocrine therapy (randomly assigned) and if they had a luminal A or luminal B tumor subtypes. The benefit of tamoxifen in 25-year distant recurrence–free survival was substantial in both groups (luminal A subtype: 70% [95% CI, 62%-79%] for untreated patients vs 87% [95% CI, 82%-93%] for treated patients; P < .001; luminal B subtype: 54% [95% CI, 42%-70%] for untreated patients vs 67% [95% CI, 56%-82%] for treated patients; P = .04). These data should encourage the use of tamoxifen when appropriate. They had a substantial follow-up time (25 years), which is necessary to fully appreciate the influence of any intervention in patients with low-risk breast cancer. Overall, 21.6% of the patients experienced a distant recurrence.1