Impaired Glucose Metabolism and Oxidative Stress of Diabetes Mellitus in Causation of Breast Cancer

Breast cancer (BC) and Diabetes Mellitus (DM) are medical conditions that are becoming more common in many developed nations. When compared with healthy individuals, diabetic people have an elevated risk of BC and more fatalities from the disease. This implies an association and that the two conditions share risk factors and pathophysiological pathways. Although the causal processes beneath this connection remain incompletely understood, plausible ties include hyperinsulinemia, insulin resistance, oxidative stress, chronic inflammation, hyperglycaemia, and hormonal. Each of these conditions has been proposed for fostering tumour progression in numerous manners. Although hyperglycaemia is one of the most extensively researched metabolic abnormalities in DM, the consequences of high blood sugar on malignancy have garnered less scrutiny than the influence of insulin, insulin-like growth factor-1 (IGF-1), oxidative stress, and chronic inflammation on the progression of cancer. The purpose of this chapter is to provide insight into the link between impaired glycaemic status and oxidative stress of DM with the causation, type, progression, and mortality of BC. Several unexplored areas exist, and new hypotheses may emerge in the days to come.