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    Breast Cancer Prevention (Holistic)

    Breast Cancer Prevention (Holistic)

    About This Condition

    A healthy lifestyle offers protection now. What changes can you make to reduce your breast cancer risk or ease your treatment? According to research or other evidence, the following self-care steps may be helpful.
    • Get a checkup

      See your healthcare professional once a year for a breast exam and mammogram to detect disease before it becomes advanced

    • Cut back on cocktails, but not on nutrition

      Limit your alcohol consumption and take a multivitamin containing folic acid to reduce alcohol-related breast cancer risk

    • Eat risk-reducing foods

      Add plenty of fiber, tomato products, soy products, and fish to your diet

    • Seek support

      If you have breast cancer, join a weekly patients? group for social support

    About

    About This Condition

    Breast cancer is a malignancy of the breast that is common in women and rare in men. It is characterized by unregulated replication of cells creating tumors, with the possibility of some of the cells spreading to other sites (metastasis).

    This article includes a discussion of studies that have assessed whether certain vitamins, minerals, herbs, or other dietary ingredients offered in dietary or herbal supplements may be beneficial in connection with the reduction of risk of developing breast cancer.

    This information is provided solely to aid consumers in discussing supplements with their healthcare providers. It is not advised, nor is this information intended to advocate, promote, or encourage self prescription of these supplements for cancer risk reduction or treatment. Furthermore, none of this information should be misconstrued to suggest that dietary or herbal supplements can or should be used in place of conventional anticancer approaches or treatments.  

    It should be noted that certain studies referenced below, indicating the potential usefulness of a particular dietary ingredient or dietary or herbal supplement in connection with the reduction of risk of breast cancer, are preliminary evidence only. Some studies suggest an association between high blood or dietary levels of a particular dietary ingredient with a reduced risk of developing breast cancer. Even if such an association were established, this does not mean that dietary supplements containing large amounts of the dietary ingredient will necessarily have a cancer risk reduction effect.

    Most breast cancer is not hereditary, although a small percentage of women have a genetic weakness that dramatically increases their risk. Women with a strong family history of breast cancer may choose to explore the possibility of genetic testing with a geneticist, found on the staff of many major hospitals.

    The incidence of postmenopausal breast cancer varies dramatically from one part of the world to the other, and those who move from one country to another will, on average, over time, begin to take on the risk of the new society to which they have moved. This evidence strongly suggests that most, though not all, breast cancer is preventable. However, great controversy exists about which factors are most responsible for the large differences in breast cancer incidence that separate high-risk populations from low-risk populations.

    A few factors that affect the risk of having breast cancer are widely accepted:

    • The later the age of the first menstrual cycle, the lower the risk.
    • Full-term pregnancy at an early age (teens to early twenties) lowers risk.
    • Being overweight increases the risk of postmenopausal breast cancer.
    • Use of hormone replacement therapy increases the risk, but this increase in risk has been reported to disappear shortly after hormone use is discontinued.
    • Being older at the time of the last menstrual cycle (early fifties or older) confers a higher risk compared with women who have had their last menstrual cycle at a younger age (late forties or earlier).

    Several other factors may affect a woman?s risk of getting breast cancer. Many researchers and some doctors believe that long-term (greater than five years) use of oral contraceptives increases the risk of premenopausal breast cancer, but not the risk of postmenopausal breast cancer. Also, being overweight appears to slightly reduce the risk of premenopausal breast cancer, even though it increases the risk of postmenopausal breast cancer.

    Almost all women with noninvasive breast cancer (ductal carcinoma in situ), along with a majority of women diagnosed with node-negative invasive breast cancer, are cured with appropriate conventional treatment. Even when breast cancer is diagnosed after it has spread to lymph nodes, many patients are curable. Once breast cancer has spread to a distant part of the body, conventional treatment sometimes extends life but cannot provide a cure.

    Symptoms

    The diagnosis of breast cancer is usually begun at the time a painless one-sided lump is discovered by the woman or her physician. In recent years, the diagnosis of breast cancer often begins with suspicious findings from a routine screening mammogram accompanied by no symptoms. In more advanced cases, changes to the contour of the affected breast may occur, and the lump may eventually become immovable.

    If breast cancer spreads to a distant part of the body (distal metastasis), symptoms are determined by the location to which the cancer has spread. For example, if breast cancer spreads to bone, it frequently causes bone pain; if it spreads to the brain, it generally causes neurological symptoms, such as headaches that do not respond to aspirin. When it has spread to a distant part of the body, breast cancer also eventually causes severe weight loss, untreatable fatigue-inducing anemia, and finally death.

    Healthy Lifestyle Tips

    The following lifestyle changes have been studied in connection with breast cancer.

    Exercise and prevention

    Girls who engage in a significant amount of exercise have been reported to be less likely to get breast cancer as adults.1 Although some doctors speculate that exercise in preadolescent girls might reduce the risk of eventually getting breast cancer by reducing the number of menstrual cycles and therefore exposure to estrogen, these effects may occur only in girls engaging in very strenuous exercise.2

    Most,3 , 4 but not all,5 studies find that adult women who exercise are less likely to get breast cancer. Women who exercise have also been reported to have a reduced risk of high-risk mammography patterns compared with inactive women.6

    Exercise in adulthood might help protect against breast cancer by lowering blood levels of estrogen or by helping maintain ideal body weight. In addition to the preventive effects of exercise, aerobic exercise has been reported to reduce depression and anxiety in women already diagnosed with breast cancer.7

    Smoking and risk

    Some studies have found an association between smoking and an increased risk of breast cancer, including exposure to secondhand smoke.8 However, several reports have either found no association9 or have reported an association between smoking and an apparent protection against breast cancer.10 Some of the studies reporting that smoking is detrimental have found that exposure to cigarette smoke during childhood appears to be most likely to increase the risk of breast cancer.11

    The mind-body connection

    In some studies, the risk of breast cancer has been reported to be higher in women who have experienced major (though not minor) depression in the years preceding diagnosis.12 Some,13 , 14 but not all,15 studies have found that exposure to severely stressful events increases a woman?s chance of developing breast cancer. In one study, breast cancer patients exposed to severely stressful events, such as death of a spouse or divorce, had more than five times the risk of suffering a recurrence compared with women not exposed to such stressors.16 Although stress has long been considered as a possible risk factor, some studies have not found significant correlations between psychological stressors and breast cancer risk17 or the risk of breast cancer recurrence.18 Similarly, experiencing psychological distress (independent of external stressors) has, in some reports, not been associated with a reduction in survival or the risk of suffering a breast cancer recurrence.19

    Exposure to psychological stress has been reported to weaken the immune system of breast cancer patients.20 Strong social support has been reported to increase immune function in breast cancer patients.21 These findings suggest a possible way in which the mind might play a role in affecting the risk of a breast cancer recurrence.22 , 23

    In one study, breast cancer patients with strong social support in the months following surgery had only half the risk of dying from the disease during a seven-year period compared with patients who lacked anyone to confide in.24 After 1025 and 15 years,26 breast cancer patients with a helpless and hopeless attitude or with an attitude of stoicism were much less likely to survive compared with women who had what the researchers called a ?fighting spirit.? In a five-year study, the same helpless/hopeless attitude correlated with an increased risk of recurrence or death in breast cancer patients, but a ?fighting spirit? did not correlate with special protection against recurrence or death.27 One trial reported that psychological therapy for hopeless/helpless breast cancer patients was capable of changing these attitudes and reducing psychological distress in only eight weeks.28

    Several trials using a variety of psychological interventions have reported increased life expectancy in women receiving counseling or psychotherapy compared with women who did not receive psychological intervention29?even in women with late-stage disease.30 In a now-famous trial, late-stage breast cancer patients in a year-long, 90-minute-per-week support group lived on average twice as long as a group of similar patients who did not receive such support.31

    Finally, relaxation training has been reported to reduce psychological distress in breast cancer patients,32 and group therapy and hypnosis have reduced pain in late-stage breast cancer patients.33

    Even extensive psychological support (weekly peer support, family therapy, individual counseling, and use of positive mental imagery) has not led to a clear increase in breast cancer survival in every study.34 Why some studies clearly find mind-body connections in regard to breast cancer risk, recurrence, or survival, while other studies find no such connection, remains unclear.

    Overweight and risk

    Being overweight increases the risk of postmenopausal breast cancer, a fact widely accepted by the research community. Overweight does not increase the risk of premenopausal breast cancer and even may be associated with a slightly reduced risk of breast cancer in young women.35

    Eating Right

    The right diet is the key to managing many diseases and to improving general quality of life. For this condition, scientific research has found benefit in the following healthy eating tips.

    Recommendation Why
    Choose your fat wisely
    Women in countries that eat high amounts of meat and dairy fat have a high breast cancer risk, while women in countries that mostly eat rice, soy, vegetables, and fish have a low risk.

    High-fat diets increase the risk of mammary cancer in animals.36 From country to country, breast cancer risk in women is proportionate to the level of total fat consumed in the diet.37 Estrogen levels, body weight, and breast density have all been reported to decrease when women are put on low-fat diets?all changes that are thought to reduce the risk of breast cancer.38 , 39 , 40 , 41 Moreover, breast cancer patients have been reported to reduce their chances of survival by eating a diet high in saturated fat.42 (Saturated fat is found mostly in meat and dairy fat.) Similarly, breast cancer patients have been reported to be at increased risk of suffering a recurrence if they eat higher levels of fatty foods, such as butter, margarine, red meat, and bacon.43

    Analysis of human trials, using a research design dependent on the memories of subjects, also has shown women consuming high-fat diets to be at high risk of breast cancer.44 In some cases, the correlation has been quite strong.45 However, most,46 , 47 , 48 but not all,49?prospective? studies?which avoid problems caused by faulty memories?have not found any association between fat intake and the risk of breast cancer.

    Why do some research findings suggest that fat increases the risk of cancer and other studies find no association? Some studies finding dietary fat unrelated to cancer risks have not factored out the effects of olive oil or fish fat; both may protect against cancer.50 , 51 , 52 , 53 Adding them to the total dietary fat intake and then studying whether ?more fat causes more cancer? is therefore misleading. Some studies finding no association between fat intake and breast cancer have made one or both of these errors.54 , 55

    Scientists know cancers caused by diet most likely occur many years after the causative foods are regularly consumed. When one group of researchers compared dietary intakes to cancer rates occurring ten years after the consumption of food, and also eliminated from consideration the effect of fat from fish consumption, they found a high degree of correlation between consumption of animal fat (other than from fish) and the risk of breast cancer death rates for women at least 50 years of age.56

    In the debate over whether dietary fat increases breast cancer risks, only one fact is indisputable: women in countries that consume high amounts of meat and dairy fat have a high risk of breast cancer, while women in countries that mostly consume rice, soy, vegetables, and fish (instead of dairy fat and meat) have a low risk of breast cancer.57

    Feast on fiber
    Many studies have shown that people who eat plenty of whole grains have a lower risk for breast cancer.

    Insoluble fiber from grains delays the onset of mammary (breast) cancer in animals.58 In an analysis of the data from many studies, people who eat relatively high amounts of whole grains were reported to be at low risk for breast cancer.59

    In some studies, the protective effect of fiber against the risk of breast cancer has been stronger in young women than in older women.60 This finding might occur because fiber has been reported to lower estrogen levels in premenopausal women but not in postmenopausal women.61 , 62 Other researchers, however, report that fiber appears to equally reduce the risk of breast cancer in women of all ages.63 One leading researcher has suggested the active components in fiber may be phytate and isoflavones, substances that may provide protection even in the absence of a decrease in estrogen levels.64 If these substances do protect against breast cancer, they might be as helpful in older women as in younger women.

    Consuming a diet high in insoluble fiber is best achieved by switching from white rice to brown rice and from bakery goods made with white flour or mixed flours to 100% whole wheat bread, whole rye crackers, and whole grain pancake mixes. Refined white flour is generally listed on food packaging labels as ?flour,??enriched flour,??unbleached flour,??durum wheat,??semolina,? or ?white flour.? Breads containing only whole wheat are usually labeled ?100% whole wheat.?

    Fill up on fruits and veggies
    Although not proven, a diet high in fruits and vegetables may afford some protection against breast cancer.

    An analysis of 17 studies on breast cancer risk and diet found that high consumption of vegetables was associated with a 25% decreased risk of breast cancer compared with low consumption.65 The same report analyzed 12 studies that found high consumption of fruit was associated with a 6% reduction of breast cancer incidence compared with low consumption. However, when data from only the eight largest and best studies were combined, high intake of fruits and/or vegetables did not correlate with protection from breast cancer.66 Therefore, the protective effect of fruit and vegetable consumption against breast cancer remains unproven.67

    Go fish
    Fish eaters have been reported to have a low risk of breast cancer, possibly due to fish?s high omega-3 fatty acid content.

    Fish eaters have been reported to have a low risk of breast cancer.68 The omega-3 fatty acids found in fish are thought by some researchers to be the components of fish responsible for protection against cancer.69

    Go vegetarian
    Compared with meat eaters, most studies have found that vegetarians are less likely to be diagnosed with cancer.

    Compared with meat eaters, most,70 but not all,71 studies have found that vegetarians are less likely to be diagnosed with cancer. Vegetarians have also been shown to have stronger immune functioning , possibly explaining why vegetarians may be partially protected against cancer.72 Female vegetarians have been reported to have lower estrogen levels compared with meat-eating women, possibly explaining a lower incidence of breast cancer that has been reported in vegetarian women.73

    Pour on the olive oil
    Olive oil in the diet has been associated with low breast cancer risk in some preliminary reports.

    Olive oil consumption has been associated with a reduced risk of breast cancer in several preliminary reports.74 , 75 , 76 Oleic acid, the main fatty acid found in olive oil, does not appear to be the cause of this protective effect,77 and scientists now guess that some as-yet undiscovered substance in olive oil might be responsible for the apparent protective effect of olive oil consumption.78

    Stay tuned about soy
    The commonly held belief that eating soy foods will protect against breast cancer is far from proven.

    Asian countries in which soy consumption is high generally have a low incidence of breast cancer. However, the dietary habits in these countries are so different from diets in high-risk countries that attributing protection from breast cancer specifically to soy foods on the basis of this evidence alone is premature.79 Similarly, within a society, women who frequently consume tofu have been reported to be at low risk of breast cancer.80 Consumption of tofu might only be a marker for other dietary or lifestyle factors that are responsible for protection against breast cancer.

    Genistein, one of the isoflavones found in many soy foods, inhibits proliferation of breast cancer cells in test tube studies. Most animal studies report that soybeans and soy isoflavones protect against mammary cancer.81 However, the protective effect in animals have occurred primarily when soy has been administered before puberty.82 If the same holds true in humans, consuming soy products in adulthood might provide little, if any, protection against breast cancer.

    The findings of several recent studies suggest that consuming soy might, under some circumstances, increase the risk of breast cancer.83 , 84 , 85 , 86 , 87 When ovaries were removed from animals?a situation related to the condition of women who have had a total hysterectomy?dietary genistein was reported to increase the proliferation of breast cancer cells.88 When pregnant rats were given genistein injections, their female offspring were reported to be at greater risk of breast cancer.89 Although premenopausal women have shown decreases in estrogen levels in response to soy consumption,90 , 91 proestrogenic effects have also been reported.92 When premenopausal women were given soy isoflavones, an increase in breast secretions resulted?an effect thought to elevate the risk of breast cancer.93 In yet another trial, healthy breast cells from women previously given soy supplements containing isoflavones showed an increase in proliferation rates?an effect that might also increase the risk of breast cancer.94

    The commonly held belief that consuming soybeans or isoflavones such as genistein will protect against breast cancer is, therefore, far from proven.95 , 96 , 97 , 98 , 99 Possibly, consuming soybeans in childhood may ultimately be proven to have a protective effect.100 Doing the same in adulthood, however, may have very different effects.101 , 102 , 103 , 104 , 105

    Some scientists, at least under some circumstances, remain hopeful about the potential for soy to protect against breast cancer. These scientists recommend consumption of foods made from soy (such as tofu), as opposed to taking isoflavone supplements. Several substances in soybeans other than isoflavones have shown anticancer activity in preliminary research.106

    Team up with tomatoes
    High in the antioxidant lycopene, tomatoes have been shown to protect against a variety of cancers including breast cancer.

    Tomatoes contain lycopene ?an antioxidant similar in structure to beta-carotene . Most lycopene in our diet comes from tomatoes, though traces of lycopene exist in other foods. Lycopene has been reported to inhibit the proliferation of cancer cells in test tube research.107

    A review of published research found that higher intake of tomatoes or higher blood levels of lycopene correlated with a reduced risk of a variety of cancers in 57 of 72 studies. Findings in 35 of these studies were statistically significant.108 Evidence of a protective effect for tomato consumption was strongest for cancers other than breast cancer ( prostate , lung , and stomach cancer), but some evidence of a protective effect also appeared for breast cancer.

    Cut down on alcohol
    Limit your intake to lower your risk: Studies show that women who drink alcohol have a higher breast cancer risk than those who abstain.

    An analysis of studies using the best available methodology found that women who drink alcohol have a higher risk of breast cancer compared with teetotalers.109 Alcohol consumption during early adulthood may be more of a risk factor than alcohol consumption at a later age.110

    Some,111 , 112 though not all,113 studies have reported that alcohol increases estrogen levels. Increased estrogen levels might explain the increase in risk.

    In a preliminary report, drinkers with low intake of folic acid had a 32% increased risk of breast cancer compared with nondrinkers; however, the excess risk was only 5% in those drinkers who consumed adequate levels of folic acid.114 In the same report, women taking multivitamins containing folic acid and having at least 1.5 drinks per day had a 26% lower risk of being diagnosed with breast cancer compared with women drinking the same amount of alcohol but not taking folic acid-containing vitamins.115

    Reduce your sugar
    Studies have shown that women who eat high amounts of sugar-containing foods have had an increased breast cancer risk, whether the association may be due to other dietary or lifestyle factors is unknown.

    Preliminary studies have reported associations between an increased intake of sugar or sugar-containing foods and an increased risk of breast cancer,116 though this link does not appear consistently in published research.117 Whether these associations exist because sugar directly promotes cancer or because sugar consumption is only a marker for some other dietary or lifestyle factor remains unknown.

    Watch the meat
    Some studies have shown that eating meat is linked to increased breast cancer risk, although the association may depend on whether the meat is well-done, which introduces more carcinogens.

    Most,118 , 119 but not all,120 studies show that consumption of meat is associated with an increased risk of breast cancer. This association probably depends in part on how well the meat is cooked. Well-done meat contains more carcinogenic material than does lightly cooked meat.121 Evidence from preliminary studies shows that women who eat well-done meat have a high risk of breast cancer.122 Genetic factors may determine which women increase their risk of breast cancer by eating well-done meat.123

    Supplements

    What Are Star Ratings?

    Our proprietary ?Star-Rating? system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.

    For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.

    3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.

    2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

    1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

    Supplement Why
    2 Stars
    Folic Acid
    400 mcg daily
    For women who drink alcohol, folic acid may reduce breast cancer risk by reversing the damaging effect alcohol has on DNA.

    Among women who drink alcohol, those who consume relatively high amounts of folate from their diet have been reported to be at reduced risk of breast cancer, compared with women who drink alcohol but consumed less folate, according to a preliminary study.124 In a similar report, consumption of folic acid-containing supplements was associated with a lower risk of breast cancer in women who drank alcohol, compared with women who drank alcohol but did not take such supplements.125

    The damaging effect alcohol has on DNA?the material responsible for normal replication of cells?is partially reversed by folic acid. Therefore, a potential association between both dietary folate and folic acid supplements and protection against breast cancer in women who drink alcohol is consistent with our understanding of the biochemical effects of these substances. A combined intake from food and supplements of at least 600 mcg per day was associated with a 43% reduced risk of breast cancer in women who consumed 1.5 drinks per day or more, compared with women who drank the same amount but did not take folic acid-containing supplements.126

    1 Star
    Conjugated Linoleic Acid
    Refer to label instructions
    Preliminary research suggests that CLA might reduce breast cancer risk.

    Preliminary animal and test tube research suggests that CLA might reduce the risk of cancers at several sites, including breast , prostate , colorectal , lung , skin, and stomach.127 , 128 , 129 , 130 Whether CLA will have a similar protective effect for people has yet to be demonstrated in human research.

    1 Star
    Vitamin D
    Refer to label instructions
    Vitamin D from supplements and from exposure to the sun both appear to protect against breast cancer.

    Breast cancer rates have been reported to be relatively high in areas of low exposure to sunlight.131 Sunlight triggers the formation of vitamin D in the skin, which can be activated in the liver and kidneys into a hormone with great activity. This activated form of vitamin D causes ?cellular differentiation??essentially the opposite of cancer.

    The following evidence indicates that vitamin D might have a protective role against breast cancer:

    • Synthetic vitamin D-like molecules have prevented the equivalent of breast cancer in animals.132
    • Activated vitamin D appears to have antiestrogenic activity.133
    • Both sunlight and dietary exposure to vitamin D have correlated with a reduced risk of breast cancer.134 , 135

    Activated vitamin D comes in several forms. One of them?1,25 dihydroxycholecalciferol?is an exact duplicate of the hormone made in the human body.

    The following preliminary, non-clinical evidence supports the idea that activated vitamin D may be of help to some breast cancer patients:

    • In combination with tamoxifen , a synthetic, activated-vitamin D-like molecule has inhibited the growth of breast cancer cells in test tube research.136
    • Synthetic vitamin D-like molecules induce tumor cell death in breast cancer cells.137
    • Activated vitamin D suppresses the growth of human cancer cells transplanted into animals.138
    • In test tube research, activated vitamin D has increased the anticancer action of chemotherapy.139

    In a preliminary trial, activated vitamin D was applied topically to the breast, once per day for six weeks, in 19 patients with breast cancer.140 Of the 14 patients who completed the trial, three showed a large reduction in tumor size, and one showed a minor improvement. Those who responded had tumors that contained receptors for activated vitamin D. However, other preliminary reports have not found that high levels of these receptors consistently correlate with a better outcome.141 , 142 , 143

    With a doctor?s prescription, compounding pharmacists can put activated vitamin D, a hormone, into a topical ointment. Due to potential toxicity, use of this hormone, even topically, requires careful monitoring by a physician. Standard vitamin D supplements are unlikely to duplicate the effects of activated vitamin D in women with breast cancer. The patients in the breast cancer trial all had locally advanced disease.

    References

    1. Marcus PM, Newman B, Moorman PG, et al. Physical activity at age 12 and adult breast cancer risk (United States). Cancer Causes Control 1999;10:293?302.

    2. Bullen BA, Skrinar GS, Beitins IZ, et al. Induction of menstrual disorders by strenuous exercise in untrained women. N Engl J Med 1985;312:1349?53.

    3. Rockhill B, Willett WC, Hunter DJ, et al. A prospective study of recreational physical activity and breast cancer risk. Arch Intern Med 1999;159:2290?6.

    4. Thune I, Brenn T, Lund E, Gaard M. Physical activity and the risk of breast cancer. N Engl J Med 1997;336:1269?75.

    5. Gammon MD, Schoenberg JB, Britton JA, et al. Recreational physical activity and breast cancer risk among women under age 45 years. Am J Epidemiol 1998;147:273?80.

    6. Gram IT, Funkhouser E, Tabar L. Moderate physical activity in relation to mammographic patterns. Cancer Epidemiol Biomarkers Prev 1999;8:117?22.

    7. Segar ML, Katch VL, Roth RS, et al. The effect of aerobic exercise on self-esteem and depressive and anxiety symptoms among breast cancer survivors. Oncol Nurs Forum 1998;25:107?13.

    8. Johnson KC, Hu J, Mao Y, & The Canadian Cancer Registries Epidemiology Research Group. Passive and active smoking and breast cancer risk in Canada, 1994?7. Cancer Causes Control 2000;11:211?21.

    9. London SJ, Colditz GA, Stampfer JM, et al. Prospective study of smoking and the risk of breast cancer. J Natl Cancer Inst 1989;81:1625?31.

    10. Gammon MD, Schoenberg JB, Teitelbaum SL, et al. Cigarette smoking and breast cancer risk among young women (United States). Cancer Causes Control 1998;9:583?90.

    11. Lash TJ, Aschengrau A. Active and passive cigarette smoking and the occurrence of breast cancer. Am J Epidemiol 1999;149:5?12.

    12. Gallo JJ, Armenian HK, Ford DE. Major depression and cancer: the 13-year follow-up of the Baltimore Epidemiologic Catchment Area sample (United States). Cancer Causes Control 2000;11:751?8.

    13. Chen CC, David AS, Nunnerley H, et al. Adverse life events and breast cancer: case-control study. BMJ 1995;311:1527?30.

    14. Geyer S. Life events prior to manifestation of breast cancer: a limited prospective study covering eight years before diagnosis. J Psychosomatic Res 1991;35:355?63.

    15. Protheroe D, Turvey K, Horgan K, et al. Stressful life events and difficulties and onset of breast cancer: case-control study. BMJ 1999;319:1027?30.

    16. Ramirez AJ, Craig TK, Watson JP, et al. Stress and relapse of breast cancer. BMJ 1989;298:291?3.

    17. Roberts FD, Newcomb PA, Trentham-Dietz A, Storer BE. Self-reported stress and risk of breast cancer. Cancer 1996;77:1089?93.

    18. Barraclough J, Pinder P, Cruddas M, et al. Life events and breast cancer prognosis. BMJ 1992;304:1078?81.

    19. Tross S, Herndon J II, Korzun A, et al. Psychological symptoms and disease-free and overall survival in women with stage II breast cancer. J Natl Cancer Inst 1996;88:661?7.

    20. Andersen BL, Farrar WB, Golden-Kreutz D, et al. Stress and immune response after surgical treatment for regional breast cancer. J Natl Cancer Inst 1998;90:30?6.

    21. Levy SM, Herberman RB, Whiteside T, et al. Perceived social support and tumor estrogen/progesterone receptor status as predictors of natural killer cell activity in breast cancer patients. Psychosomatic Med 1990;52:73?85.

    22. Andersen BL, Farrar WB, Golden-Kreutz D, et al. Stress and immune response after surgical treatment for regional breast cancer. J Natl Cancer Inst 1998;90:30?6.

    23. Levy SM, Herberman RB, Whiteside T, et al. Perceived social support and tumor estrogen/progesterone receptor status as predictors of natural killer cell activity in breast cancer patients. Psychosomatic Med 1990;52:73?85.

    24. Mausell E, Brisson J, Deschênes L. Social support and survival among women with breast cancer. Cancer 1995;76:631?7.

    25. Pettingall KW, Morris T, Greer S, Haybittle JL. Mental attitudes to cancer: an additional prognostic factor. Lancet 1985;i:750.

    26. Greer S, Morris T, Pettingale KW, Haybittle JL. Psychological response to breast cancer and 15-year outcome. Lancet 1990;335:49?50 [letter].

    27. Watson M, Haviland JS, Greer S, et all. Influence of psychological response on survival in breast cancer: a population-based cohort study. Lancet 1999;354:1331?6.

    28. Greer S, Moorey S, Baruch JDR, et al. Adjuvant psychological therapy for patients with cancer: a prospective randomised trial. Lancet 1992;304:675?80.

    29. Simonton OC, Matthews-Simonton S. Cancer and stress. Counseling the cancer patients. Med J Aust 1981;1:679?83.

    30. Grossarth-Maticek R, Eysenck HJ. Length of survival and lymphocyte percentage in women with mammary cancer as a function of psychotherapy. Psychol Rep 1989;65:315?21.

    31. Spiegel D, Bloom JR, Kraemer HC, Gottheil. Effect of psychosocial treatment on survival of patients with metastatic breast cancer. Lancet 1989;ii:888?91.

    32. Bridge LR, Benson P, Pietroni PC, Priest RG. Relaxation and imagery in the treatment of breast cancer. BMJ 1988;297:1169?72.

    33. Spiegel D, Bloom JR. Group therapy and hypnosis reduce metastatic breast carcinoma pain. Psychosom Med 1983;45:333?9.

    34. Gellert GA, Maxwell RM, Siegel BS. Survival of breast cancer patients receiving adjunctive psychosocial support therapy: a 10-year follow-up study. J Clin Oncol 1993;11:66?9.

    35. Peacock SL, White E, Daling JR, et al. Relation between obesity and breast cancer in young women. Am J Epidmeiol 1999;149:339?46.

    36. Fay MP, Freedman LS, Clifford CK, Midthune DN. Effect of different types and amounts of fat on the development of mammary tumors in rodents: a review. Cancer Res 1997;57:3979?88.

    37. Armstrong B, Doll R. Environmental factors and cancer incidence and mortality in different countries, with special reference to dietary practices. Int J Cancer 1975;15:617?31.

    38. Boyar AP, Rose DP, Loughridge JR, et al. Response to a diet low in total fat in women with postmenopausal breast cancer: a pilot study. Nutr Cancer 1988;11:93?9.

    39. Bagga D, Ashley JM, Geffrey SP, et al. Effects of a very low fat, high fiber diet on serum hormones and menstrual function. Cancer 1995;76:2491?6.

    40. Chlebowski RT, Blackburn GL, Buzzard IM, et al. Adherence to a dietary fat intake reduction program in postmenopausal women receiving therapy for early breast cancer. J Clin Oncol 1993;11:2072?80.

    41. Boyd NF, Greenberg C, Lockwood G, et al. Effects at two years of a low-fat, high-carbohydrate diet on radiologic features of the breast: results from a randomized trial. J Natl Cancer Inst1997;89:488?96.

    42. Jain M, Miller AB, To T. Premorbid diet and the prognosis of women with breast cancer. J Natl Cancer Inst 1994;86:1390?7.

    43. Herbert JR, Hurley TG, Ma Yunsheng. The effect of dietary exposures on recurrence and mortality in early stage breast cancer. Breast Cancer Res Treat 1998;51:17?28.

    44. Howe GR, Hirohata T, Hislop G, et al. Dietary factors and risk of breast cancer : combined analysis of 12 case-control studies. J Natl Cancer Inst 19990;82:561?9.

    45. Toniolo P, Riboli E, Protta F, et al. Calorie-providing nutrients and risk of breast cancer. J Natl Cancer Inst 1989;81:278?6.

    46. Holmes MD, Hunter DH, Colditz GA, et al. Association of dietary intake of fat and fatty acids with risk of breast cancer. JAMA 1999;281:914?20.

    47. Jones DY, Schatzkin A, Green SB, et al. Dietary fat and breast cancer in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study. J Natl Cancer Inst 1987;79:465?71.

    48. Newman SC, Miller AB, Howe GR. A study of the effect of weight and dietary fat on breast cancer survival time. Am J Epidemiol 1986;123:767?74.

    49. Howe GR, Friedenreich CM, Jain M, Miller AB. A cohort study of fat intake and risk of breast cancer. J Natl Cancer Inst 1991;83:336?40.

    50. Trichopoulou A, Katsouyanni K, Stuver S, et al. Consumption of olive and specific food groups in relation to breast cancer risk in Greece. J Natl Cancer Inst 1995;87:110?6.

    51. La Vecchia C, Negri E, Franceschi S, et al. Olive oil, other dietary fats, and the risk of breast cancer (Italy). Cancer Causes Control 1995;6:545?50.

    52. Martin-Moreno JM, Willett WC, Gorgojo L, et al. Dietary fat, olive oil intake and breast cancer risk. Int J Cancer 1994;58:774?80.

    53. Kaizer L, Boyd NF, Kriukov V, Tritchler D. Fish consumption and breast cancer risk: an ecological study. Nutr Cancer 1989;12:61?8.

    54. Jones DY, Schatzkin A, Green SB, et al. Dietary fat and breast cancer in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study. J Natl Cancer Inst 1987;79:465?71.

    55. Newman SC, Miller AB, Howe GR. A study of the effect of weight and dietary fat on breast cancer survival time. Am J Epidemiol 1986;123:767?74.

    56. Saskai S, Moracsek M, Kesteloot H. An ecological study of the relationship between dietary fat intake and breast cancer mortality. Prev Med 1993;22:187?202.

    57. Armstrong B, Doll R. Environmental factors and cancer incidence and mortality in different countries, with special reference to dietary practices. Int J Cancer 1975;15:617?31.

    58. Rao GN, Ney E, Herbert RA. Influence of diet on mammary cancer in transgenic mice bearing an oncogene expressed in mammary tissue. Breast Cancer Res Treat 1997;45:149?58.

    59. Jacobs DR Jr, Marquart L, Salvin J, Kushi LH. Whole-grain intake and cancer: an expanded review and meta-analysis. Nutr Cancer 1998;30:85?96.

    60. La Vecchia C, Ferraroni M, Franceschi S, et al. Fibers and breast cancer risk. Nutr Cancer 1997;28:264?9.

    61. Golden BR, Woods MN, Spiegelman DL, et al. The effect of dietary fat and fiber on serum estrogen concentrations in premenopausal women under controlled dietary conditions. Cancer 1994;74(3 Suppl):1125?31.

    62. Stark AH, Switzer BR, Atwood JR, et al. Estrogen profiles in postmenopausal African-American women in a wheat bran fiber intervention study. Nutr Cancer 1998;31:138?42.

    63. Baghurst PA, Rohan TE. High-fiber diets and reduced risk of breast cancer. Int J Cancer 1994;56:173?6.

    64. Cohen LA. Dietary fiber and breast cancer. Anticancer Res 1999;19:3685?8.

    65. Gandini S, Merzenich H, Robertson C, Boyle P. Meta-analysis of studies on breast cancer risk and diet: the role of fruit and vegetable consumption and the intake of associated micronutrients. Eur J Cancer 2000;36:636?46.

    66. Smith-Warner SA, Spiegelman D, Yaun SS, et al. Intake of fruits and vegetables and risk of breast cancer. A polled analysis of cohort studies. JAMA 2001;285:769?76.

    67. Smith-Warner SA, Spiegelman D, Yaun SS, et al. Intake of fruits and vegetables and risk of breast cancer. A polled analysis of cohort studies. JAMA 2001;285:769?76.

    68. Kaizer L, Boyd NF, Kriukov V, Tritchler D. Fish consumption and breast cancer risk: an ecological study. Nutr Cancer 1989;12:61?8.

    69. Rose DP, Connolley JM. Omega-3 fatty acids as cancer chemopreventive agents. Pharmacol Ther 1999;83:217?44.

    70. Frentzel-Beyme R, Chang-Claude J. Vegetarian diets and colon cancer: the German experience. Am J Clin Nutr 1994;59(suppl):1143?52S.

    71. Kinlen LJ, Hermon C, Smith PG. A proportionate study of cancer mortality among members of a vegetarian society. Br J Cancer 1983;48:355?61.

    72. Malter M, Schriever G, Eilber U. Natural killer cells, vitamins, and other blood components of vegetarian and omnivorous men. Nutr Cancer 1989;32:271?8.

    73. Armstrong BK, Brown JB, Clarke HT, et al. Diet and reproductive hormones: a study of vegetarian and nonvegetarian postmenopausal women. J Natl Cancer Inst 1981:67:761?7.

    74. Trichopoulou A, Katsouyanni K, Stuver S, et al. Consumption of olive and specific food groups in relation to breast cancer risk in Greece. J Natl Cancer Inst 1995;87:110?6.

    75. La Vecchia C, Negri E, Franceschi S, et al. Olive oil, other dietary fats, and the risk of breast cancer (Italy). Cancer Causes Control 1995;6:545?50.

    76. Martin-Moreno JM, Willett WC, Gorgojo L, et al. Dietary fat, olive oil intake and breast cancer risk. Int J Cancer 1994;58:774?80.

    77. Shun-Zhang Y, Rui-Fang L, Da-Dao X, Howe GR. A case-control study of dietary and nondietary risk factors for breast cancer in Shanghai. Cancer Res 1990;50:5017?21.

    78. Simonsen NR, Navajas JF-C, Martin-Moreno JM, et al. Tissue stores of individual monounsaturated fatty acids and breast cancer: the EURAMIC study. Am J Clin Nutr 1998;68:134?41.

    79. Wu AH, Ziegler RG, Nomura AMY, et al. Soy intake and risk of breast cancer in Asians and Asian Americans. Am J Clin Nutr 1998;68(suppl):1437?43S [review].

    80. Wu AH, Ziegler RG, Horn-Ross PL, et al. Tofu and risk of breast cancer in Asian-Americans. Cancer Epidemiol Biomarkers Prev 1996;5:901?6.

    81. Messina MJ, Persky V, Setchell KDR, Barnes S. Soy intake and cancer risk: a review of the in vitro and in vivo data. Nutr Cancer 1994;21:113?31 [review].

    82. Messina MJ. Legumes and soybeans: overview of their nutritional profiles and health effects. Am J Clin Nutr 1999;70(suppl):439?50S [review].

    83. Barnes S. The chemopreventive properties of soy isoflavonoids in animal models of breast cancer. Breast Cancer Res Treat 1997;46:169?79 [review].

    84. Hilakivi-Clarke L, Cho E, Onojafe I, et al. Maternal exposure to genistein during pregnancy increases carcinogen-induced mammary tumorigenesis in female rat offspring. Oncol Rep 1999;6:1089?95.

    85. Hargreaves DNF, Potten CS, Harding C, et al. Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast. J Clin Endocrinol Metab 1999;84:4017?24.

    86. Petrakis NL, Barnes S, King EB, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiol Biomarkers Prev 1996;5:785?94.

    87. McMichael-Phillips DF, Harding C, Morton M, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. Am J Clin Nutr 1998;68(suppl):1431?6S.

    88. Barnes S. The chemopreventive properties of soy isoflavonoids in animal models of breast cancer. Breast Cancer Res Treat 1997;46:169?79 [review].

    89. Hilakivi-Clarke L, Cho E, Onojafe I, et al. Maternal exposure to genistein during pregnancy increases carcinogen-induced mammary tumorigenesis in female rat offspring. Oncol Rep 1999;6:1089?95.

    90. Lu LJ, Anderson KE, Grady JJ, Nagamani M. Effects of soya consumption for one month on steroid hormones in premenopausal women: implications for breast cancer risk reduction. Cancer Epidemiol Biomarkers Prev 1996;5:63?70.

    91. Nagato C, Takatsuka N, Inaba S, et al. Effect of soymilk consumption on serum estrogen concentrations in premenopausal Japanese women. J Natl Cancer Inst 1998;90:1830?5.

    92. Hargreaves DNF, Potten CS, Harding C, et al. Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast. J Clin Endocrinol Metab 1999;84:4017?24.

    93. Petrakis NL, Barnes S, King EB, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiol Biomarkers Prev 1996;5:785?94.

    94. McMichael-Phillips DF, Harding C, Morton M, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. Am J Clin Nutr 1998;68(suppl):1431?6S.

    95. Barnes S. The chemopreventive properties of soy isoflavonoids in animal models of breast cancer. Breast Cancer Res Treat 1997;46:169?79 [review].

    96. Hilakivi-Clarke L, Cho E, Onojafe I, et al. Maternal exposure to genistein during pregnancy increases carcinogen-induced mammary tumorigenesis in female rat offspring. Oncol Rep 1999;6:1089?95.

    97. Hargreaves DNF, Potten CS, Harding C, et al. Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast. J Clin Endocrinol Metab 1999;84:4017?24.

    98. Petrakis NL, Barnes S, King EB, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiol Biomarkers Prev 1996;5:785?94.

    99. McMichael-Phillips DF, Harding C, Morton M, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. Am J Clin Nutr 1998;68(suppl):1431?6S.

    100. Messina MJ. Legumes and soybeans: overview of their nutritional profiles and health effects. Am J Clin Nutr 1999;70(suppl):439?50S [review].

    101. Barnes S. The chemopreventive properties of soy isoflavonoids in animal models of breast cancer. Breast Cancer Res Treat 1997;46:169?79 [review].

    102. Hilakivi-Clarke L, Cho E, Onojafe I, et al. Maternal exposure to genistein during pregnancy increases carcinogen-induced mammary tumorigenesis in female rat offspring. Oncol Rep 1999;6:1089?95.

    103. Hargreaves DNF, Potten CS, Harding C, et al. Two-week dietary soy supplementation has an estrogenic effect on normal premenopausal breast. J Clin Endocrinol Metab 1999;84:4017?24.

    104. Petrakis NL, Barnes S, King EB, et al. Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiol Biomarkers Prev 1996;5:785?94.

    105. McMichael-Phillips DF, Harding C, Morton M, et al. Effects of soy-protein supplementation on epithelial proliferation in the histologically normal human breast. Am J Clin Nutr 1998;68(suppl):1431?6S.

    106. Messina M, Barnes S. The role of soy products in reducing risk of cancer. J Natl Cancer Inst 1991;83:541?6 [review].

    107. Levy J, Bosin E, Feldman B, et al. Lycopene is a more potent inhibitor of human cancer cell proliferation than either a-carotene or ß-carotene. Nutr Cancer 1995;24:257?66.

    108. Giovannucci E. Tomatoes, tomato-based products, lycopene, and cancer: review of the epidemiologic literature. J Natl Cancer Inst 1999;91:317?31.

    109. Smith-Warner SA, Spiegelman D, Yaun SS, et al. Alcohol and breast cancer in women. A pooled analysis of cohort studies. JAMA 1998;279:535?40.

    110. Garland M, Hunter DJ, Colditz GA, et al. Alcohol consumption in relation to breast cancer risk in a cohort of United States women 25?42 years of age. Cancer Epidemiol Biomarkers Prev 1999;8:1017?21.

    111. Purohit V. Moderate alcohol consumption and estrogen levels in postmenopausal women: a review. Alcohol Clin Exp Res 1998;22:994?7.

    112. Ginsburg ES, Mello NK, Mendelson JH, et al. Effects of alcohol ingestion on estrogens in postmenopausal women. JAMA 1996;276:1747?51.

    113. Becker U, Gluud C, Bennet P, et al. Effect of alcohol and glucose infusion on pituitary-gonadal hormones in normal females. Drug Alcohol Depend 1988;22:141?9.

    114. Zhang S, Hunter DJ, Hankinson SE, et al. A prospective study of folate intake and the risk of breast cancer. JAMA 1999;281:1632?7.

    115. Zhang S, Hunter DJ, Hankinson SE, et al. A prospective study of folate intake and the risk of breast cancer. JAMA 1999;281:1632?7.

    116. Burley VJ. Sugar consumption and human cancer in sites other than the digestive tract. Eur J Cancer Prev 1998;7:253?77 [review].

    117. Decarli A, Favero A, La Vecchia C, et al. Macronutrients, energy intake, and breast cancer risk: implications from different models. Epidemiology 1997;8:425?8.

    118. Zheng W, Gustafson DR, Sinha R, et al. Well-done meat intake and the risk of breast cancer. J Natl Cancer Inst 1998;90:1724?9.

    119. De Stefani E, Ronco A, Mendilaharsu M, et al. Meat intake, heterocyclic amines, and risk of breast cancer : a case-control study in Uruguay. Cancer Epidemiol Biomarkers Prev 1997;6:573?81.

    120. Ambrosone CB, Freudenheim JL, Sinha R, et al. Breast cancer risk, meat consumption and N-acetyltransferase (NAT2) genetic polymorphisms. Int J Cancer 1998;75:825?30.

    121. Bjeldanes LF, Morris MM, Felton JS, et al. Effect of meat composition and cooking conditions on mutagen formation in fried ground beef. J Agriculture Food Chem 1983;31:18?21.

    122. Zheng W, Gustafson DR, Sinha R, et al. Well-done meat intake and the risk of breast cancer. J Natl Cancer Inst 1998;90:1724?9.

    123. Zheng W, Deitz AC, Campbell DR, et al. N-acetyltransferase 1 genetic polymorphism, cigarette smoking, well-done meat intake, and breast cancer risk. Cancer Epidemiol Biomarkers Prev 1999;8:233?9.

    124. Rohan TE, Jain MG, Howe GR, Miller AB. Dietary folate consumption and breast cancer risk. J Natl Cancer Inst 2000;92:266?9.

    125. Zhang S, Hunter DJ, Hankinson SE, et al. A prospective study of folate intake and the risk of breast cancer. JAMA 1999;281:1632?7.

    126. Zhang S, Hunter DJ, Hankinson SE, et al. A prospective study of folate intake and the risk of breast cancer. JAMA 1999;281:1632?7.

    127. Cesano A, Visonneau S, Scimeca JA, et al. Opposite effects of linoleic acid and conjugated linoleic acid on human prostatic cancer in SCID mice. Anticancer Res 1998;18:1429-34.

    128. Thompson H, Zhu Z, Banni S, et al. Morphological and biochemical status of the mammary gland as influenced by conjugated linoleic acid: implication for a reduction in mammary cancer risk. Cancer Res 1997;57:5067-72.

    129. Ip C. Review of the effects of trans fatty acids, oleic acid, n-3 polyunsaturated fatty acids, and conjugated linoleic acid on mammary carcinogenesis in animals. Am J Clin Nutr 1997;66(suppl):1523S-29S [review].

    130. Parodi PW. Cows? milk fat components as potential anticarcinogenic agents. J Nutr 1997;127:1055-60 [review].

    131. Gorham ED, Garland FC, Garland CF. Sunlight and breast cancer incidence in the USSR. Int J Epidemiol 1990;19:820?4.

    132. Anzano MA, Smith JM, Uskokovic, et al. 1a,25-dihydroxy-16-ene-23-yne-26,27-hexafluorocholecalciferol (Ro24?5531), a new deltanoid (vitamin D analogue) for prevention of breast cancer in the rat. Cancer Res 1994;54:1653?6.

    133. Demdirpence E, Balaguer P, Trousse F, et al. Antiestrogenic effects of all-trans-retinoic acid and 1,25-dihydroxyvitamin D3 in breast cancer cells occur at the estrogen response element level but through different molecular mechanisms. Cancer Res 1994;54:1458?64.

    134. John EM, Schwartz GG, Dreon DM, Koo J. Vitamin D and breast cancer risk: the NHANES I Epidemiologic follow-up study, 1971?1975 to 1992. Cancer Epidemiol Biomarkers Prev 1999;8:399?406.

    135. Robien K, Cutler GJ, Lazovich D. Vitamin D intake and breast cancer risk in postmenopausal women: the Iowa Women's Health Study. Cancer Causes Control 2007;18:775?82.

    136. Vink-van Wijngaarden T, Pols HA, Buurman CJ, et al. Inhibition of breast cancer cell growth by combined treatment with vitamin D3 analogues and tamoxifen. Cancer Res 1994;54:5711?7.

    137. James SY, Merceer E, Brady M, et al. ERB1089, a synthetic analogue of vitamin D, induces apoptosis in breast cancer cells in vivo and in vitro. Br J Pharmacol 1998;125:953?62.

    138. Eisman JA, Barkla DH, Tutton PJM. Suppression of in vitro growth of human cancer solid tumor xenografts by 1,25-dihydroxyvitamin D3. Cancer Res 1987;47:21?5.

    139. Ravid A, Rocker D, Machlenkin A, et al. 1,25-dihydroxyvitamin D3 enhances the susceptibility of breast cancer cells to doxorubicin-induced oxidative damage. Cancer Res 1999;59:862?7.

    140. Bower M, Colston KW, Stein RC, et al. Topical calcipotriol treatment in advanced breast cancer. Lancet 1991;337:701?2.

    141. Colston KW, Berger U, Coombes RC. Possible role for vitamin D in controlling breast cancer cell proliferation. Lancet 1989;I:188?91.

    142. Eisman JA, Suva LJ, Martin TJ. Significance of 1,25-dihydroxyvitamin D3 receptor in primary breast cancer. Cancer Res 1986;46:5406?8.

    143. Freake HC, Abeyasekera G, Iwasaki J, et al. Measurement of 1,25-dihydroxyvitamin D3 receptors in breast cancer and their relationship to biochemical and clinical indices. Cancer Res 1984;44:1677?81.

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