Risks and Benefits of Soy Isoflavones for Breast Cancer Survivors

Shaojung A. Hu

M. Tish Knobf

ONF 2004, 31(2), 249-263. DOI: 10.1188/04.ONF.249-263

Purpose/Objectives: To present state-of-the-art information about the risks and benefits of soy isoflavones for breast cancer survivors.

Data Sources: Published research articles, pertinent articles and books, and computerized databases.

Data Synthesis: Some epidemiologic data suggest that soy isoflavones play an important role in preventing breast cancer in Asian women and promoting women's health in a variety of ways. However, the use of soy isoflavones in women with breast cancer is controversial. Risks and benefits exist regarding the use of soy isoflavones by breast cancer survivors.

Conclusions: The use of soy isoflavones to promote health in breast cancer survivors remains controversial because of scant scientific data.

Implications for Nursing: Nurses should not only provide updated information to the public but also interpret research results carefully. More clinical trials need to be conducted on a longitudinal basis with the enrollment of breast cancer survivors.

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    References

    Adlercreutz, H. (1990). Western diet and Western diseases: Some hormonal and biochemical mechanisms and associations. Scandinavian Journal of Clinical and Laboratory Investigation Supplement, 201, 3-23.

    Adlercreutz, H. (1995). Phytoestrogens: Epidemiology and a possible role in cancer protection. Environmental Health Perspectives, 103(Suppl. 7), 103-112.

    Adlercreutz, H., Hockerstedt, K., Bannwart, C., Bloigu, S., Hamalainen, E., Fotsis, T., et al. (1987). Effect of dietary components, including lignans and phytoestrogens, on enterohepatic circulation and liver metabolism of estrogens and on sex hormone binding globulin (SHBG). Journal of Steroid Biochemistry, 27, 1135-1144.

    Adlercreutz, H., & Mazur, W. (1997). Phyto-oestrogens and Western diseases. Annals of Medicine, 29, 95-120.

    Albertazzi, P., Pansini, F., Bonaccorsi, G., Zanotti, L., Forini, E., & De Aloysio, D. (1998). The effect of dietary soy supplementation on hot flashes. Obstetrics and Gynecology, 91, 6-11.

    Albertazzi, P., Pansini, F., Bottazzi, M., Bonaccorsi, G., De Aloysio, D., & Morton, M.S. (1999). Dietary soy supplementation and phytoestrogens levels. Obstetrics and Gynecology, 94,229-231.

    American Cancer Society. (2004). Cancer facts and figures, 2004. Retrieved January 22, 2004, from http://www.cancer.org/downloads/STT/CAFF2004WSecured.pdf

    Babaknia, A. (2001). Soy/pro: Soy promotes health. Alternative Medicine, 41, 50, 52-54, 56-59.

    Baird, D.D., Umbach, D.M., Lansdell, L., Hughes, C.L., Setchell, K.D., Weinberg, C.R., et al. (1995). Dietary intervention study to assess estrogenicity of dietary soy among postmenopausal women. Journal of Endocrinology and Metabolism, 80, 1685-1690.

    Barnes, S., Sfakianos, J., Coward, L., & Kirk, M. (1996). Soy isoflavonoids and cancer prevention: Underlying biochemical and pharmacological issues. Advances in Experimental Medicine and Biology, 401, 87-100.

    Baron-Faust, R. (1995). Breast cancer: What every woman should know. New York: Hearst.

    Bascom, A. (2002). Incorporating herbal medicine into clinical practice. Philadelphia: F.A. Davis.

    Beckmann, M.W., Jap, D., Djahansouzi, S., Nestle-Krämling, C., Kuschel, B., Dall, P., et al. (2001). Hormone replacement therapy after treatment of breast cancer: Effects on postmenopausal symptoms, bone mineral density, and recurrence rates. Oncology, 60, 199-206.

    Berga, S.L. (2000). Phytoestrogens: Alternative or complementary? Menopause, 7, 213-214.

    Boon, H., Steward, M., Kennard, M.A., Gray, R., Sawka, C., Brown, J.B., et al. (2000). Use of complementary/alternative medicine by breast cancer survivors in Ontario: Prevalence and perceptions. Journal of Clinical Oncology, 18, 2515-2521.

    Brzezinski, A., Adlercreutz, H., Shaoul, R., Rösier, A., Shmueli, A., Tanos, V., et al. (1997). Short-term effects on phytoestrogen-rich diet on postmenopausal women. Menopause, 4, 89-94.

    Burke, G.L., Legault, C., Anthony, M., Bland, D.R., Morgan, T.M., Naughton, M.J., et al. (2003). Soy protein and isoflavone effects on vasomotor symptoms in peri- and postmenopausal women: The soy estrogen alternative study. Menopause, 10, 147-153.

    Burstein, H.J., Gelber, S., Guadagnoli, E., & Weeks, J.C. (1999). Use of alternative medicine by women with early-stage breast cancer. New England Journal of Medicine, 340, 1733-1739.

    Burstein, H.J., & Winer, E.P. (2000). Primary care for survivors of breast cancer. New England Journal of Medicine, 343, 1086-1094.

    Carpenter, J.S. (2000). Hot flashes and their management in breast cancer. Seminars in Oncology Nursing, 16, 214-225.

    Carter, B.J. (1993). Long-term survivors of breast cancer. Cancer Nursing, 16, 354-361.

    Carusi, D. (2000). Phytoestrogens as hormone replacement therapy: An evidence-based approach. Primary Care Update for OB/GYNS, 7, 253-259.

    Cerrato, P.L. (1998). Can plant estrogens help fightcancer?RN,61(10),59-60.

    Chapman, N. (1998). Where is the soyfoods market headed? Third Annual Soyfoods Symposium Proceedings. Retrieved May 1, 2002, from http://soyfoods.com/symposium98/ChapmanPaper98.html

    Chung, T.K.H., Yip, S.K., Lam, P., Chang, A.M.Z., & Haines, C.J. (1996). A randomized, double-blind, placebo-controlled, crossover study on the effect of oral estradiol on acute menopausal symptoms. Maturita, 25, 115-123.

    Dalais, F.S., Rice, G.E., Wahlqvist, M.L., Grehan, M., Murkies, A.L., Medley, G., et al. (1998). Effects of dietary phytoestrogens in postmenopausal women. Climacteric, 1, 124-129.

    Davis, S.R., Murkies, A.L., & Wilcox, G. (1998). Phytoestrogens in clinical practice. Integrative Medicine, 1(1), 27-34.

    Dow, K.H. (1999). Exploring quality-of-life issues in recurrent breast cancer. Innovations in Breast Cancer Care, 4(2), 39-44.

    Doyle, B. (2002). Functional foods and nutraceuticals. In M. Snyder & R. Lindquist (Eds.), Complementary/alternative therapies in nursing (4th ed., pp. 272-284). New York: Springer.

    Eden, J.A. (2000). Diet, phytoestrogens, and prevention of breast cancer. Menopause, 7, 283-285.

    Eldridge, A.C., & Kwolek, W.F. (1983). Soybean isoflavones: Effect of environment and variety on composition. Journal of Agricultural and Food Chemistry, 31, 394-396.

    Elkind-Hirsch, K. (2001). Effect of dietary phytoestrogens on hot flashes: Can soy-based proteins substitute for traditional estrogen replacement therapy? Menopause, 8, 154-156.

    Fallon, S., & Enig, M.G. (2000). Tragedy and hype: The third international soy symposium. Nexus Magazine, 7(3). Retrieved January 8, 2004, from http://www.nexusmagazine.com/soydangers.html

    Faure, E.D., Chantre, P., & Mares, P. (2002). Effects of a standardized soy extract on hot flashes: A multicenter, double-blind, placebo-controlled study. Menopause, 9, 329-334.

    Ferrell, B.R., Grant, M., Funk, B., Garcia, N., Otis-Green, S., & Schaffner, M.L. (1996). Quality of life in breast cancer. Cancer Practice, 4, 331-340.

    Fitzpatrick, L.A. (1999). Selective estrogen receptors modulator and phytoestrogens: New therapies for the postmenopausal women. Mayo Clinic Proceedings, 74, 601-607.

    Folman, Y., & Pope, G.S. (1966). The interaction in the immature mouse of potent estrogens with coumestrol, genistein, and other utero-vaginotrophic compounds of low potency. Journal of Endocrinology, 34, 215-225.

    Folman, Y., & Pope, G.S. (1969). Effect of norethisterone acetate, dimethyl-stilboestrol, genistein, and coumestrol on uptake of [3H]oestradiol by uterus, vagina, and skeletal muscle of immature mice. Journal of Endocrinology, 44, 213-218.

    Ganz, P.A., Desmond, K.A., Leedham, B., Rowland, J.H., Meyerowitz, B.E., & Belin, T.R. (2002). Quality of life in long-term, disease-free survivors of breast cancer: A follow-up study. Journal of the National Cancer Institute, 94, 39-49.

    Ganz, P.A., Rowland, J.H., Desmond, K.A., Meyerowitz, B.E., & Wyatt, G.E. (1998). Life after breast cancer: Understanding women's health-related quality of life and sexual functioning. Journal of Clinical Oncology, 16, 501-514.

    Glisson, J., Crawford, R., & Street, S. (1999). The clinical applications of ginkgo biloba, St. John's wort, saw palmetto, and soy. Nurse Practitioner, 24(6), 28, 31, 35-36.

    Greenwood, S., Barnes, S., Clarkson, T.B., Eden, J., Helferich, W.G., Hughes, C., et al. (2000). The role of isoflavones in menopausal health: Consensus opinion of the North American Menopause Society. Menopause, 7, 215-229.

    Han, K.K., Scares, J.M., Haidar, M.A., de Lima, G.R., & Baracat, B.C. (2002). Benefit of soy isoflavone therapeutic regimen on menopausal symptoms. Obstetrics and Gynecology, 99, 389-394.

    Harborne, J.B., Baxter, H., & Moss, G.P. (1999). Phytochemical dictionary: A handbook of bioactive compounds from plants (2nd ed.). Philadelphia: Taylor and Francis.

    Hasler, C.M. (2002, January). Soy: Still a functional food in the spotlight. Functional Foods for Health News, 9(2). Retrieved January 23, 2004, from http://www.reliv.com/press/functionalgoods022002.html

    Hasler, C.M., & Finn, S.C. (1998). Soy: Just a hill of beans? Journal of Women's Health, 7, 519-523.

    Ingram, D., Sanders, K., Kolybaba, M., & Lopez, D. (1997). Case control study of phytoestrogens and breast cancer. Lancet,350,990-994.

    Keeler, B., & Lappe, M. (2001, January 7). Some food for FDA regulations— GE soy is different. LA Times Health News. Retrieved January 8, 2004, from http://home.intekom.com/tm_info/rwl0123.htm#24

    Kelly, G.E., Joannou, G.E., Reeder, A.Y., Nelson, C., & Waring, M.A. (1995). The variable metabolic response to dietary isoflavones in humans. Proceedings of the Society for Experimental Biology and Medicine, 208(1), 40-43.

    Knight, D.C., & Eden, J. A. (1996). A review of the clinical effects of phytoestrogens. Obstetrics and Gynecology, 87, 897-904.

    Knobf, M.T. (2001). The menopausal symptom experience in young mid-life women with breast cancer. Cancer Nursing, 24, 201-210.

    Kronenberg, F., & Fugh-Berman, A. (2002). Complementary and alternative medicine for menopausal symptoms: A review of randomized, controlled trials. Annals of Internal Medicine, 137, 805-813.

    Lee, H.P., Gourley, L., Duffy, S.W., Esteve, J., Lee, J., & Day, N.E. (1991). Dietary effects on breast-cancer risk in Singapore. Lancet, 337, 1197-1200.

    Lock, M. (1991). Contested meaning of the menopause. Lancet, 337, 1270-1272.

    Lu, L.W., Anderson, K.E., Grady, J.J., Kohen, F., & Nagamani, M. (2000). Decreased ovarian hormones during a soy diet: Implications for breast cancer prevention. Cancer Research, 60, 4112-4121.

    Messina, M. (2000, Summer). Breast cancer, cognitive function soy safety issues examined. Soy Connection, 8(3), 1-6.

    Messina, M., Messina, V., & Setchell, K. (1994). The simple soybean and your health. New York: Avery.

    Messina, M.J., & Loprinzi, C.L. (2001). Soy for breast cancer survivors: A critical review of the literature. Journal of Nutrition, 131(Suppl. 11), 3095-3108.

    Messina, M.J., Persky, V., Setchell, K.D., & Barnes, S. (1994). Soy intake and cancer risk: A review of the in vitro and in vivo data. Nutrition and Cancer, 21, 113-131.

    Murkies, A., Dalais, F.S., Briganti, E.M., Burger, H.G., Healy, D.L., Wahlqvist, M.L., et al. (2000). Phytoestrogens and breast cancer in postmenopausal women: A case control study. Menopause, 7, 289-296.

    Murkies, A.L., Lombard, C., & Strauss, B.J.G. (1995). Dietary flour supplementation decreases postmenopausal hot flashes: Effect of soy and wheat. Maturitas, 21, 189-195.

    O'Shea, T. (2001). Soy/con: Soy is not a health food. Alternative Medicine, 41, 51, 60-65.

    Petrakis, N.L., Barnes, S., King, E.B., Lowenstein, J., Wiencke, J., Lee, M.M., et al. (1996). Stimulatory influence of soy protein isolate on breast secretion in pre- and postmenopausal women. Cancer Epidemiology, Biomarkers, and Prevention, 5, 785-794.

    Poniatowski, B.C., Grimm, P., & Cohen, G. (2001). Chemotherapy-induced menopause: A literature review. Cancer Investigation, 19, 641-648.

    Quella, S.K., Loprinzi, C.L., Barton, D.L., Knost, J.K., Sloan, J.A., LaVasseur, B.I., et al. (2000). Evaluation of soy phytoestrogens for the treatment of hot flashes in breast cancer survivors: A North Central Cancer Treatment Trial. Journal of Clinical Oncology, 18, 1068-1074.

    Scambia, G., Mango, D., Signorile, P.G., Angeli, R.A., Palena, C., Gallo, D., et al. (2000). Clinical effects of a standardized soy extract in postmenopausal women: A pilot study. Menopause, 7, 105-111.

    Seibel, M.M. (1999). The role of nutrition and nutritional supplements in women's health. Fertility and Sterility, 72, 579-591.

    Soy isoflavones. (1998). Alternative Medicine Review, 3, 376-378.

    Spake, A. (2001, February 12). Natural hazards. U.S. News and World Report, pp. 43-46, 48-49.

    St. Germain, A., Peterson, C.T., Robinson, J.G., & Alekel, D.L. (2001). Isoflavone-rich or isoflavone-poor soy protein does not reduce menopausal symptoms during 24 weeks of treatment. Menopause, 8, 17-26.

    United Soybean Board. (2002). National report 2002-2003: Consumer attitudes about nutrition. Retrieved January 22, 2004, from http://www.talksoy.com/pdfs/Consumer-Attitudes-2002.pdf

    United Soybean Board. (2003). National report 2003-2004: Consumer attitudes about nutrition. Retrieved January 22, 2004, from http://www.talksoy.com/pdfs/Consumer%20Attitudes%202003.pdf

    Upmalis, D.H., Lobo, R., Bradley, L., Warren, M., Cone, F.L., & Lamia, C.A. (2000). Vasomotor symptoms relief by soy isoflavone extract tablets in postmenopausal women: A multicenter, double-blind, randomized, placebo-controlled study. Menopause, 7, 236-242.

    Van Patten, C.L., Olivotto, I.A., Chambers, G.K., Gelmon, K.A., Hislop, T.G., Templeton, E., et al. (2002). Effect of soy phytoestrogens on hot flashes in postmenopausal women with breast cancer: A randomized, controlled clinical trial. Journal of Clinical Oncology, 20, 1449-1455.

    Vassilopoulou-Sellin, R., & Theriault, R.L., (1994). Randomized prospective trial of estrogen-replacement therapy in women with a history of breast cancer. Journal of the National Cancer Institute Monographs, 16, 153-159.

    Vincent, A., & Fitzpatrick, L. (2000). Soy isoflavones: Are they useful in menopause? Mayo Clinic Proceedings, 75, 1174-1184.

    Washburn, S., Burke, G.L., Morgan, T., & Anthony, M. (1999). Effect of soy protein supplementation on serum lipoproteins, blood pressure, and menopausal symptoms in perimenopausal women. Menopause, 6(1), 7-13.

    Welshons, W.V., Murphy, C.S., Koch, R., Calaf, G., & Jordan, V.C. (1987). Stimulation of breast cancer cells in vitro by the environmental estrogen enterolactone and the phytoestrogen equol. Breast Cancer Research and Treatment, 10, 169-175.

    Wyatt, G., Kurtz, M.E., & Liken, M. (1993). Breast cancer survivors: An exploration of quality of life issues. Cancer Nursing, 16, 440-448.

    Yuan, J.M., Wang, Q.S., Ross, R.K., Henderson, B.E., & Yu, M.C. (1995). Diet and breast cancer in Shanghai and Tianjin. British Journal of Cancer, 71, 1353-1358.