Environmental pollutants, diet, physical activity, body size, and breast cancer

Abstract

Breast cancer is the most common invasive cancer in women worldwide and the leading cause of death in US women in mid-life. Treatment has adverse effects, adding to the importance of finding modifiable risk factors. At the invitation of Susan G. Komen for the Cure, we reviewed studies of breast cancer and environmental pollutants, diet (assessed prospectively), body size, and physical activity, and animal studies that identify chemicals as potential mammary carcinogens.Databases developed in the review include information on 216 chemicals that increased mammary gland tumors in animal studies and 450 epidemiologic studies (accessible at www.silentspring.org/sciencereview and www.komen.org/ environment). Exposure to potential mammary carcinogens is widespread from chemicals found in consumer products, air and drinking water pollution, food, and women's workplaces. Epidemiologic studies have included only a small number of chemicals identified as mammary carcinogens or as hormone disruptors, which may have implications for breast cancer; however, evidence is emerging for associations between breast cancer and polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and organic solvents. Prospective diet studies have not revealed consistent associations with breast cancer. Improved exposure assessment methods will help advance future human studies of both diet and environmental pollutants. Studies of physical activity show that it is protective. In the same vein as evidence-based medicine, messages for patients, policymakers, and

Ambient air pollution is associated with the increased incidence of breast cancer in US

“…There are multiple factors that have been identified or suggested to be associated with the increased risk for breast cancer (Schon and Bellach 1995;Kelsey and Bernstein 1996;Brody et al 2007a). Among those risk factors, environmental and lifestyle factors, such as exposure to environmental pollutants, ionizing radiation, certain hormonal pharmaceuticals, alcohol consumption, diet, physical activity, and personal behavior, could play important roles in breast cancer development (Johnson-Thompson and Guthrie 2000;Brody and Rudel 2003;Brody et al 2007aBrody et al , 2007b.…”

PIK3CA and TP53 Gene Mutations in Human Breast Cancer Tumors Frequently Detected by Ion Torrent DNA Sequencing

“…Additional etiologic agents include race, hormones, tobacco and alcohol consumption, obesity, lack of childbearing, and a combination of environmental and genetic factors [4]–[6]. Genetics are estimated to be the primary causal factor in 5–10% of breast cancers, while all others develop spontaneously with an accumulation of genetic and epigenetic changes [7].…”

New Exposure Biomarkers as Tools for Breast Cancer Epidemiology, Biomonitoring, and Prevention: A Systematic Approach Based on Animal Evidence

“…We based our assessments of human evidence on IARC assessments for nine agents (Cogliano et al 2011; IARC 2012). For human evidence on heterocyclic amines and four organochlorines, we relied on other authoritative reviews (Brody et al 2007b; Hoover et al 2011; Michels et al 2007), and for five nonhormonal pharmaceuticals, we relied on an observational study from Kaiser Permanente (Friedman et al 2009). Animal study findings came from original research papers, NTP reports, and other government reports.…”

“…Breast cancer is the most common invasive malignancy among women in the United States, and the leading cause of death in women from their late 30s to early 50s (Brody et al 2007b; Woloshin et al 2008). The American Cancer Society (2010) estimated the global economic costs of premature death and disability from breast cancer at $88 billion/year.…”