Risk factors breast cancer

CYPI7 genetic polymorphism, breast cancer, and breast cancer risk factors. Breast Cancer Res. 5, R45-51. 

Breast cancer is one of the most common forms of cancer affecting women and, in Western countries, the incidence is rising. The risk of breast cancer increases markedly with age, although a decrease in the rate occurs after the menopause, suggesting that development is hormone-dependent. To date, a number of hormone-related risk factors have been identified (Bingham et al, 1998). Countries such as Japan have relatively low rates of breast cancer, which have been associated with consumption of a diet high in soy foods. Currently, however, the data from epidemiological studies is inconclusive. 

List factors associated with an increased risk of breast cancer in the United States. 

Howe G, Hirohata T, Hislop T, Iscovich J, Yuan J, Katsouyanni K, Lubin F, Marubini E, Modan B, Rohan T, Toniolo P and Shunzhang Y. 1992. Dietary factors and risk of breast cancer combined analysis of 12 case-control studies. J Nat Cancer Inst 82 561-569. 

Tumor size and the presence and number of involved axillary lymph nodes are primary factors in assessing the risk for breast cancer recurrence and subsequent metastatic disease. Other disease characteristics that provide prognostic information include histologic subtype, nuclear or histologic grade, lymphatic and vascular invasion, and proliferation indices. 

Pike MC, Krailo MD, Henderson BE (1983) Hormonal risk factors, breast tissue age and the age incidence of breast cancer. Nature 303 767-769... 

Interest in dietary components which explain differences in breast cancer rates comes from strong correlations between nutrient supply within nations and their age-adjusted rates for breast cancer (11). The most frequently cited dietary components related to higher risk of breast cancer are total fat, total protein, calories, animal fat, animal protein, and a lack of fiber. Overall it has not been possible to identify the specific dietary constituents responsible for the observed incidence since the intakes of many dietary factors such as protein, fat, and calories are strongly intercorrelated. Other studies of nutrient intake and breast... 

Stroke is a very uncommon event in childbearing women, occurring in approximately 11 per 100,000 women over a 1-year period of time. Therefore, even a doubling of this risk with oral contraceptive pills would have minimal effect on attributable risk. The estimated risk of myocardial infarction associated with oral contraceptive pill use in nonsmokers is 3 per million women over 1 year. The estimated risk of venous thromboembolism attributable to oral contraceptive pills is less than 3 per 10,000 women per year. However, the risk may be increased in women who smoke or have other predisposing factors to thrombosis or thromboembolism. In fact, it should be emphasized that the risk of serious cardiovascular side effects is particularly marked in women over 35 years of age who are heavy smokers (e.g., more than 15 cigarettes per day). Additionally, the literature suggests that there may be an increased risk of breast cancer associated with long-term oral contraceptive pill use in women under the age of 35. However, because the incidence of breast cancer is so relatively low in this population, the attributable risk of breast cancer from birth control pill use is small. 

Furthermore, a diet with low contents of FA may be involved in the development of insulin resistance, which suggests that an appropriate dietary intake of n-3 PUFA is considered protective against metabolic syndrome [183]. In addition, diverse psyquiatric impairs (depression, bipolar disorders, schizophrenia, autism) and neurodegenerative diseases such as Alzheimer disease have been associated to decreased blood levels of n-3 HUFA. Besides, there are many examples about the use of pol)nmsaturated FA as drugs. Thus, EPA has shown efficacy as adjunctive treatment, and in some cases as the only treatment in several psyquiatric disorders [184]. It is suggested that the potential of n-3 FA to prevent recurrence and metastasis of mammary cancer when used in adjuvant therapy is associated with a n-6 to n-3 ratio lower than 2 1 [185], On the other hand, fish intake is considered as a protective factor for preventing prostate cancer in addition, in humans low levels of ALA in mammary adipose tissue are associated with an increased risk of breast cancer in women [186]. 

A number of endocrine factors have been linked to the incidence of breast cancer. Many of these relate to the total duration of menstrual life. Early menarche, generally defined as menstruation begiiming before age 12, has been shown by a number of investigators to increase the cumulative lifetime risk of breast cancer development compared to menarche at age 16 or greater. Conversely, early age of natural menopause has been shown to result in a reduction of risk. Similarly, investigators have reported that bilateral oophorectomy prior to age 35 reduces the relative risk of developing breast cancer. 

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