Factors in the Causation of Female Cancers and Prevention

In this chapter, we discuss risk factors that influence the onset of female cancers. Particular emphasis is given to breast and ovarian cancers and how dietary strategies may help to reduce the risk. Reviewed topics include cancer statistics in Western and developing countries; dietary patterns that modulate the risk of cancers in female carriers of mutations in susceptibility genes and selected polymorphisms; effects of fruits and vegetables on cancer risk. We also discuss the role of diet–hormone receptor status interactions and the impact of energy balance and obesity on cancer risk and prevention. A review of the major intervention trials on diet and breast cancer indicate that dietary fat reduction and increased fruits, vegetable, and fiber intake do not provide the basis for conclusive dietary recommendation. Data are currently lacking concerning the role of healthy dietary patterns and specific nutrients in the etiology of breast cancer. Evidence from cohort and case–control studies suggests that non-starchy vegetables may protect against ovarian and endometrial cancer. There is limited but consistent evidence that carrots, containing high levels of carotenoids, including β- and α-carotene, and certain antioxidants, may be protective against cervical cancer. Results of case–control studies indicate that red meat consumption is positively associated with endometrial cancer due to heme-iron, the generation of N-nitroso compounds, and the production of heterocyclic amines and polycyclic aromatic hydrocarbons. The response to certain food components and mutagens is influenced by the interaction with genetic background including mutations in tumor susceptibility genes and polymorphisms for metabolizing genes. Future research is necessary to gain knowledge of the causal relationships between obesity, energy balance, physical activity, and the cancer process. Although caloric restriction is consistently associated with reduced mammary tumor development, it is not clear how it influences the metastatic process.