One of the most common types of cancer diagnosed is breast cancer and comes secondly in the leading causes of death among women (Rajib 2022). The highest incidence of women malignant tumors is breast cancer, it affects all ages in the world, and it is caused not only by hormonal factors, reproductive factors but also due to environmental factors (Dong et al. 2021). Siegel et al. (2020) reported that it is the commonest female malignancy in the USA, with 276,480 new cases and 42,170 deaths expected. Moreover, Shohdy et al. (2021) stated that the Egyptian females’ knowledge about breast cancer is low, although it represents 33% of female cancer cases and more than 22,000 new cases diagnosed annually. This is anticipated to increase enormously over the coming years as a result of bad lifestyle choices, population growth, and changes in the population pyramid. Despite significant increases in survival rates in many developed regions, research have shown that Egypt’s 5-year survival rate, which ranges from 28 to 68%, has stayed lower. Numerous variables, including the fact that most patients receive diagnoses at advanced stages, are thought to have contributed to the poorer survival rates (Abdelaziz et al. 2021). MetS, including obesity, diabetes, and hypertension, is associated with increased BC risk. On the other hand, MetS is gradually being evaluated as a significant predictor of BC prevalence. Many studies have correlated different aspects of breast cancer with MetS and its associated derangements (Akinyemiju et al. 2022). According to Palmiero et al. (2021), MetS plays a critical role in defining BC because of its effects on hormonal pathways involving insulin, estrogen, cytokines, and growth factors among postmenopausal women in particular, Additionally, MetS is linked to a higher chance of death from breast cancer (Buono 2020). In people with MetS, chronic inflammation and oxidative stress contribute to the development of cancer (Zhang et al. 2021). Unfavorable treatment outcomes and increased side effects are caused by metabolic abnormalities, which also raise the likelihood of developing the disease and hasten tumor growth. Furthermore, due to the imbalance of these metabolic components, biochemical processes influence both the host’s overall health and the tumor microenvironment unique to a particular organ, leading to higher rates of recurrence and mortality (Dong et al. 2021). While many studies assessed the relationship between BC risk and each individual MetS factor, such as abdominal visceral adiposity, serum lipid levels, and insulin and glucose levels, only a small number of studies attempted to consider multiple items of the cluster of MetS that are associated with BC risk. Early BC diagnosis is a tough issue in clinical practice today. As a result, it is helpful for BC prevention to have proof indicating that postmenopausal women with MetS have a significant risk of developing BC (Palmiero et al. 2021). Obesity, along with increased tumor burden and higher histopathological grade, is all linked to a higher risk of postmenopausal breast cancer (Dong et al. 2021). Given that adipose tissue is the primary source of estrogen in postmenopausal women and that excessive estrogen is known to drive the growth of breast tissue, one of the risk factors for breast cancer is an increase in the body’s estrogen levels brought on by obesity (Dong et al. 2021).
Obese women have up to twice as much estrogen as normal weight women because after menopause, estrogen is primarily produced in body fat instead of a woman’s ovaries. Additionally, obese women have lower levels of the protein “sex hormone binding globulin,” which binds to and removes estrogen from the body. Women who are overweight and obese typically have higher insulin levels than lean women. Any potential relationship between insulin levels and breast cancer risk in premenopausal women is less evident (Mili et al. 2021). Changes in body size as measured by height, weight, body mass index (BMI), waist–hip ratio (WHR), waist circumference, and waist-to-height ratio (WHTR) are substantially related to breast cancer (WC). All of these metrics are discovered to be associated with menopausal status, and their significance is connected to levels of androgen and estrogen (Choi et al. 2021). Results from many studies continue to be contradictory, nevertheless. Surprisingly, women’s sex steroid hormone synthesis depends heavily on peripheral fat tissue. Because estrogen and androgens are mitogenic mediators for breast cells, obesity after menopause increases their levels. Additionally, obesity is a reflection of poor eating habits and inactivity, both of which are linked to the development of breast cancer (Buono 2020).
In Western Europe, breast cancer affects more than 30% of patients, and obesity and physical inactivity are associated to it. Recently, anthropometric factors (high BMI and obesity, poor physical activity), smoking, unhealthy eating practices (low consumption of fruits and vegetables), and different treatments (injections, hormonal replacement therapy) have been identified as BC risk factors (Stankeviča et al. 2021). Obesity is thought to be a substantial risk factor for breast cancer and increases the mortality rate in postmenopausal women. The distinct stage of cancer, its size, angiolymphatic invasion, and lymph node involvement in the metastatic stage are all negatively impacted by adiposity. Breast cancer with obesity has aggressive tumor characteristics and a high death rate. The computation of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and the skin fold thickness measuring test are the most widely used and efficient methods of evaluating adiposity (Stankeviča et al. 2021). The current study aimed to investigate the incidence of metabolic syndrome among Egyptian women with breast cancer as independent risk factor, and the relationships between anthropometric indices (BMI, waist, hip, middle upper arm circumferences) and breast cancer risk.