The pathogenesis of cancer is not fully understood. There are two theories in the 2015.1, the risk of cancer tissue and stem cell division n
The pathogenesis of cancer is not fully understood. There are two theories in the 2015.
1, the risk of cancer tissue and stem cell division number, 2/3 of the cancer is due to "bad luck", DNA repair is also random mutations occur in non cancer cells of the normal, only 1/3 can be attributed to environmental factors or genetic predisposition. [TomasettiCetal.Science.2015Jan2; 347 (6217): 78-81.]
2, and another proposed "cancer is the product of evolution", in addition to mutational activation of cancer organizations need and age related changes to obtain more favorable conditions to win in the competition and healthy cells. The organization of ecosystem health and promote the healthy cells over the cancerous cells when the organization ecosystem changes such as aging, smoking or other pressure effect, the cancerous cells can quickly adapt to changes in the environment, and natural selection in generations of inheritance. More emphasis on the influence of foreign factors [AndriiI.RozhokandJamesDeGregori, UniversityofColoradoSchoolofMedicine, PNAS|July212015|vol.112|no.29|8914-8921]
No matter what theory suggests that cancer is related to environmental factors and lifestyle, but the proportion is different.
The relevant factors of breast cancer in the US can change are: age, primiparous lactation, exogenous estrogen, lifestyle factors and drugs. The treatment of breast cancer has achieved good results, the treatment can improve the survival rate of absolute if 1% is quite easy, if you can reduce the incidence rate of 1%, the value is greater (treatment, then the perfect treatment after all is "trauma"). The World Cancer Research Fund and the American Association for cancer research (TheWorldCancerResearchFund/AmericanInstituteforCancerResearch (WCRF/AICR) estimates more than 40% post menopause breast cancer can be reduced by excessive alcohol intake, reduce weight, increase the exercise to prevent. (WorldCancerResearchFundInternational:Cancerpreventabilityestimatesforfood, nutrition, bodyfatness, andphysicalactivity.http://www.wcrf.org/cancer_statistics/preventability_estimates/preventability_estimates_food.php.).
The relationship between lifestyle and breast cancer.
1 obesity and breast cancer: two reports of obesity as a risk factor for breast cancer
Looking at the relationship between weight change and breast cancer risk in women aged 50 years and older, according to the European Prospective Investigation Group on cancer and nutrition () in 2014 (EPIC). Found that middle-aged women gain weight will increase the risk of breast cancer, and this relationship appears to be for 50 years before the diagnosis of breast cancer is more significant. The findings suggest that middle-aged women should control their weight to prevent breast cancer. [MarleenJ.Emausetal.Int.J.Cancer:1352887 - 2899 (2014)]
In 2014, Fourkala, a British researcher, found that the risk of developing breast cancer in postmenopausal women would increase by 33% over the course of a period of up to one year in every 10 years, from the age of 25 to menopause. [Evangelia-OuraniaFourkalaetal.BMJOpen2014; 4:e005400.].
2 smoking and breast cancer:
A study was conducted in 2014 by the European cancer and nutrition prospective survey team to assess the association between passive and active smoking and invasive breast cancer. A total of 322988 women were enrolled in the study. In the end, a total of 9822 women with breast cancer (in which, there were 183608 women who smoked passively, and eventually had a breast cancer of the breast) in the last 6264 years. The results showed that compared with never smokers and women are not passive smoking, current smoking (hazard ratio HR=1.16, 95%CI=1.05 - 1.28), former smokers (HR=1.14, 95%CI=1.04-1.25) and is currently passive smoking (HR=1.10,95%CI=1.01-1.20), which can increase the risk of breast cancer. Menarche to first full-term pregnancy between smoking and breast cancer risk is higher. [LaureDossusetal.Int.J.Cancer:1341871 - 1888 (2014)]
A prospective cohort study from Canada in 2014 showed that smoking may be a risk factor for breast cancer, and the risk of breast cancer is related to the duration of smoking. The study included 89835 women, aged 40~59 years, with an average follow-up of 22.1 months, followed by a total of 6549 subjects with breast cancer. The results showed that the risk of breast cancer was related to the length of time, the intensity of exposure, and the cumulative exposure. Women who smoked before the first pregnancy had a higher risk of breast cancer than women who smoked during pregnancy. The experiment confirms the female patients with active smoking can increase the risk of breast cancer, suggesting that in the primary prevention of breast cancer should be as an important content of tobacco control. [CatsburgCetal.Int.J.Cancer.Publishedonline:23OCT2014.]
3 alcohol and breast cancer:
A daily increase in alcohol intake, breast cancer risk increased by 7-10%. In the nurses' health study, a weekly intake of alcohol and non drinkers than 4-9 units, more than 15% increased risk for breast cancer. Higher intake (more than 27 units a week), the risk of breast cancer than non drinkers 51%. (1 units for the 4% half pint of beer or wine) [ChenWY, RosnerB, HankinsonSE, ColditzGA, WillettWC:Moderatealcoholconsumptionduringadultlife, drinkingpatterns, andbreastcancerrisk.JAMA2011306:1884 - 1890]
4 mental stress
A study of 157 breast cancer patients and 314 control subjects from June 2009 to June 2011 in Taiwan, China, was conducted to investigate the relationship between psychological stress and lifestyle and breast cancer risk. The results showed that mental stress (adjusted odds ratio AOR=1.65; 95% confidence interval CI, 1.10 - 2.47), weekly physical activity less than 1000lcal (AOR=2.17; 95%CI=1.39, 3.39), a high intake of fried foods (AOR=1.86; 95%CI=1.24, 2.77) will increase the risk of breast cancer. [LEEWANGetal.Women& Health, 53:20 - 402013]
5 exogenous estrogen (hint: pay attention to nutrition application).
The use of exogenous hormones increased breast cancer risk [PenelopeMWebbetal.FutureOncol. (2015)] (2) (295 - 307) ()
A study by PrithwishDe, a professor at the Canadian Cancer Society, showed a reduction in hormone replacement therapy since 2002. The largest decline in the use of hormone replacement therapy in women aged 50 to 69 occurred between January 1, 2002 and December 31, 2004, down from 12.7% to 4.9%. At the same time, the incidence of breast cancer has decreased by 9.6%. Hormone replacement therapy may increase the risk of breast cancer in women aged 50-69 in canada. [PrithwishDeetal.JNatlCancerInst2010; 102:1489 - 1495]
Have the opposite results: Professor Cerne and his team from Slovenia conducted a study to evaluate the treatment of Slovenia in postmenopausal women using hormone replacement (HRT) and the influence of some putative breast cancer risk factors on breast cancer incidence. A total of 784 cases of 50-69 years old were enrolled in the study group and the control group (n = 709). Use of hormone replacement therapy reduces the risk of breast cancer. [J.Z.Cerneetal.CLIMACTERIC2011; 14:458 - 463]
6 exercise and exercise
Moderate exercise can reduce the risk of breast cancer in postmenopausal women: a study of 59000 postmenopausal women in the prospective cohort study in France found that, compared with the less active women, moderate exercise (the only daily at a comfortable speed walk for more than and 30 minutes, or ahead of a station, or a car to go shopping for a week. Walk for 4 hours) women diagnosed with invasive breast cancer risk reduction of 10% (HR=0.9), especially in the first 4 years and actively participate in the exercise of women. Some women in the pre 5-10 years of moderate exercise, but during lazy, the risk of breast cancer is not reduced, indicating that only exercise can reduce the risk of breast cancer. [AgnesFournieretal.CancerEpidemiolBiomarkersPrev; 2014; (9); 1893 - 1902]
Professor Phillips of the women's University Hospital in Toronto reviewed the literature on the relationship between body size and physical activity and BRCA mutations in breast cancer. Some studies have shown that a healthy body and physical exercise (especially in adolescence) can reduce the risk of breast cancer in BRCA carriers. [RachaelPettapiece-Phillipsetal.CancerCausesControl (2015) 26:333 - 344)
Vegetables and fruits can reduce the incidence of cancer [AhmadFaizalAbdullRazisetal.AsianPacificJCancerPrev, 2013; 14 (3), 1565-1570]
Antioxidant dietary components: a prospective cohort study from the United States show that the risk of dietary antioxidants are more people suffering from breast cancer is low, such as antioxidants in the diet of dietary carotenoids and flavonoids of food may be limited to certain subgroups, such as smokers and the elderly. * antioxidants (vitamin A, C, E, selenium, flavonoids and carotenoids) [AthanasiosPantavosetal.Int.J.Cancer.Publishedonline:18OCT2014.]