Adjuvant systemic treatment in luminal breast cancer — what else apart from hormone therapy?

Abstract

The luminal subtype [hormone receptor (HR) expression and absence of HER2 overexpression] occurs in more than 70% of patients with early breast cancer. These patients are characterized with a differentiated prognosis depending on the stage and the biological aggressiveness of the tumor, which can be assessed by examining the degree of HR expression, histological malignancy (grade, G), the severity of tumor cell proliferation (Ki67 index) or gene expression in a molecular test. Besides, the young age of the patient, especially under 35 years, is associated with a worse prognosis. In all patients with HR expression, indications for adjuvant hormone therapy should be considered. However, in patients with a higher risk of relapse and death, there are additional systemic treatment options that can reduce this risk: chemotherapy and targeted drugs (cyclin-dependent kinase 4/6 inhibitors, PARP inhibitor for patients with germline BRCA 1/2 mutation). The aim of the review is to discuss indications for these forms of adjuvant therapy in HR+ HER2– patients.