ABSTRACT
Cancer-related mortality is a huge health and financial burden globally. Breast cancer (BC) particularly is a major public health concern worldwide, affecting millions of women every year. According to World Health Organization (WHO), worldwide cancer is currently a prominent source of mortality, with a clear-cut tendency towards increasing prevalence and growing social burden over the next 30 years. Cancer is the second main cause of death, and according to an estimate, cancer accounted for 9.6 million deaths in 2018. According to another estimate, by 2040 more than 29 million people are estimated to be diagnosed with some type of cancer. BC, according to WHO, is the most frequent type of carcinoma diagnosed among women worldwide, and it is the second reason for cancer death followed by lung cancer among females in the United States. BC not only affects the quality of life but also the psychological state of the patient, and in women is the primary cause of mortality. Major problems in BC are limited effectiveness, side effects, and increasing treatment resistance, which emphasizes the need for novel therapeutic approaches to treat this terrible illness. Although treatment methods have improved over the past several years, patients with metastatic breast cancer (MBC) continue to have poor survival rates, with a typical survival period of just 2–3 years. Some traditional chemotherapy has been linked to significant side effects like harm to healthy cells and a limited ability to entirely cure specific tumors. Conventional chemotherapy schedules have increased survival rates, but they also have many negative side effects, including toxicity and the emergence of drug resistance. Metronomic chemotherapy (MCT) is frequently recommended as an alternative to address the problems with traditional treatment. For cancer patients, especially those with BC, MCT is a new alternative therapeutic option. It entails the continual administration of small dosages of chemotherapeutic medications without lengthy drug-free intervals. MCT has excellent toxicity characteristics, is economically feasible, and has therapeutic benefits. Patients’ quality of life is improved by MCT's reduced toxicity profile compared to typical chemotherapy regimens, especially for those with recurrent illness. MCT is the term for the daily delivery of traditional chemotherapeutic medicines at low doses. This chapter provides information about metronomic chemotherapy including the toxicity profiles, drugs used in MCT, optimal biological doses, biomarkers, resistance, and pharmacogenetic information.
