Prognostic assessment and systemic treatments of invasive local relapses of hormone receptor-positive breast cancer

The rate of local recurrences, after breast-conserving surgery or mastectomy for hormone receptor-positive (HR+) breast cancer, has dramatically changed in last decades, due to advances in surgical and radiation techniques and a more extensive use of adjuvant systemic treatments. However, the occurrence of local recurrences remains a major predictor for distant metastasis and is responsible for increased cancer-specific death. It has been estimated that 1 in 4 HR+ and HR-ipsilateral breast recurrences leads to widespread metastatic disease, with an annual mortality rate of 10% in the first 5 years. Nevertheless, very few studies have been conducted to evaluate the optimal care of purely HR+ local relapses of breast cancer, after surgical removal. In this review we have highlighted the available knowledge on prognostic assessment and systemic treatment for women experiencing local relapses of HR+ breast cancers, underlying unsolved questions and controversial clinical aspects.