Metronomic chemotherapy and breast cancer: a critical evaluation of its role in the new landscape of therapeutics.

Introduction: Breast cancer (BC) remains a prevalent and challenging malignancy among women, with significant advancements in treatment strategies over the past decades. Traditional chemotherapy has been progressively supplemented by newer modalities, including Antibody-Drug Conjugates (ADCs), Immunotherapy (IO), and Targeted Therapies (TT). Despite these advancements, there remains a critical need for strategies that maintain efficacy while minimizing toxicity.

Areas covered: This review delves into metronomic chemotherapy (MC), a novel approach involving the frequent administration of low-dose chemotherapy without prolonged breaks. We explore MC's impact across various breast cancer subtypes, such as Estrogen Receptor-Positive (ER+), HER2-Positive, and Triple-Negative Breast Cancer (TNBC). The literature reviewed highlights MC's mechanisms, including its anti-angiogenic, immunomodulatory, and antiproliferative effects, and its potential to improve treatment tolerability and address drug resistance.

Expert opinion: MC represents a promising adjunct to existing therapies, particularly in advanced or resistant cases. Its unique dosing schedule could offer sustained antitumor activity with reduced toxicity, making it a viable option for long-term management. However, further research is warranted to establish optimal dosing regimens, identify predictive biomarkers, and delineate its role within combination treatment strategies. Clarifying these aspects could refine MC's application, potentially reshaping treatment paradigms and enhancing patient outcomes in breast cancer management.