All Forms of Hormone Replacement Therapy (HRT) Increase Breast Cancer Risk
July 11, 2010 by admin
Filed under Breast Cancer, HRT, Hormone Replacement Therapy, Weekly Health Update
Welcome to Weekly Health Update“A critical weekly review of important new research findings for health-conscious readers” ALL FORMS OF HORMONE REPLACEMENT THERAPY (HRT) INCREASE BREAST CANCER RISK One of the most common questions that I am asked is if there are any safe forms of hormone replacement therapy (HRT) for women who are experiencing severe symptoms associated with menopause. Since the release of the preliminary results of the pivotal Women’s Health Initiative study, in 2002, which clearly showed that standard combination HRT (containing the two primary female sex hormones) was associated with a significant increase in the risk of developing breast cancer, a number of alternative “safer” forms of HRT have been proposed. These alternative forms of HRT have included transdermal estrogen patches (which are placed on the skin) and other forms of “bioidentical” HRT hormones. Advocates of transdermal estrogen patches note that the adverse effects of estrogen-based HRT pills on cholesterol, as well as their association with an increased risk of life-threatening blood clots, may be lower with transdermal patches when compared to oral HRT medications. Proponents of “bioidentical” HRT, in which the active ingredient is the same chemical form of estrogen (estradiol) that is manufactured in the ovaries prior to menopause, have also made abundant health-related claims for this form of HRT when compared to the more commonly prescribed cocktail of mixed forms of estrogen derived from the urine of pregnant mares. Unfortunately, there is almost no solid clinical research evidence available to support these claims that “bioidentical” HRT is safer, or more effective, than the more commonly prescribed “conjugated equine estrogens.” (Within the estrogen-sensitive cells of a woman’s body, estrogen receptors really don’t care much whether estrogen-like hormones come from horse urine or from the human form of estrogen; nor do they care whether or not estrogen-like hormones enter the body in the form of a pill versus being absorbed into the bloodstream through a transdermal patch.) As the Women’s Health Initiative study’s breast cancer risk findings were far more robust for the combination HRT pill that has been commonly prescribed for menopausal women (because estrogen-alone HRT increases the risk of uterine cancer, as well…), many patients, and their doctors, have held out the hope that low-dose estrogen-only HRT might be a safer alternative to traditional combination HRT. However, a recently published research paper from the enormous European EPIC public health study casts serious doubt about the assumption that alternative forms of HRT are safe from the standpoint of breast cancer risk. This research paper, which has been published in the International Journal of Cancer, is an update of the huge European Prospective Investigation into Cancer and Nutrition (EPIC) study, in which 134,744 postmenopausal women throughout Europe were evaluated. After nearly 9 years of follow-up, on average, 4,312 new cases of breast cancer were diagnosed within this extremely large group of patient volunteers. When compared to women who had never used HRT, the women who were currently using combination HRT during the course of this clinical study experienced a 77 percent increase in the relative risk of developing breast cancer (similar to what has been shown in the Women’s Health Initiative study, and in other similar prospective clinical research studies). However, the greater contribution of this study to our understanding of the risks of HRT was the finding that estrogen-only HRT also increased the risk of breast cancer, as there was a 42 percent increase in the relative risk of breast cancer among the women who were taking various forms of estrogen-only HRT. Moreover, this increased breast cancer risk among users of estrogen-only HRT was the same for both oral and transdermal forms of estrogen-only HRT. The results of this giant, multi-national prospective public health study are of great importance, as it is many times larger than most of the studies that have preceded it, including the Women’s Health Initiative study. These results from the ongoing EPIC study emphasize the point that I have made to patients for almost two decades, now: The biology of the receptors in cells that respond to estrogen, and other estrogen-like molecules, has been well understood for decades now. Any substance that stimulates these estrogen receptors automatically sets off a cascade of biochemical reactions with the same end biological result. We have long known that prolonged exposure to estrogen (whether from a woman’s own ovaries, or from HRT medications) increases the risk of breast and uterine cancer, and also increases the risk of blood clots, gallstones, and other serious illnesses. (More recent data has also implicated combination HRT in the development of cardiovascular disease and dementia in women.) Based upon the findings of this very large prospective public health study, my advice to women remains the same as it has been for almost 20 years. If you are going through menopause, do not use HRT medications. If you are already using HRT medications, then ask your doctor to help in weaning you off of them. If you are one of the approximately 3 to 5 percent of postmenopausal women who have unbearably severe hot flashes, or other severe symptoms of menopause, and you are currently using some form of HRT medication, then work with your doctor to reduce the dose of your HRT medicine to the lowest possible level that adequately treats your symptoms.
For more information on HRT and cancer, please click on the following links to my previous columns on this topic: Hormone Replacement Therapy (HRT) & Ovarian Cancer Hormone Replacement Therapy (HRT) & Breast Cancer; Stool DNA Testing & Cancer of the Colon & Rectum Minority Women, Hormone Replacement Therapy & Breast Cancer; Does Health Insurance Improve Health?
To learn more about the critical role of hormone replacement medications and the risk of cancer, look for the publication of my new landmark book, “A Cancer Prevention Guide for the Human Race,” in the summer of this year. Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity Dr. Wascher is an oncologic surgeon, a professor of surgery, a cancer researcher, an oncology consultant, and a widely published author For a different perspective on Dr. Wascher, please click on the following YouTube link: http://www.youtube.com/watch?v=7-Tdv7XW0qg I and the staff of Weekly Health Update would like to take this opportunity to thank the more than 100,000 new and returning readers who visit our premier global health information website every month. As always, we enjoy receiving your stimulating feedback and questions, and I will continue to try and personally answer as many of your inquiries as I possibly can. |
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Chemotherapy for Breast Cancer & Memory Loss
May 2, 2010 by admin
Filed under Breast Cancer, Cancer, Weekly Health Update, dementia, memory
Welcome to Weekly Health Update“A critical weekly review of important new research findings for health-conscious readers”
CHEMOTHERAPY FOR BREAST CANCER & MEMORY LOSS “Chemo Brain” is a term often used by breast cancer patients to describe the decreased memory, and other cognitive dysfunctions, associated with chemotherapy for this common form of cancer. However, there has been very little prospective, objective clinical research into this phenomenon. Furthermore, what little research that has been done in this area, to date, has primarily focused upon subjective self-assessments, by breast cancer patients, of their own level of cognitive function following chemotherapy. Moreover, until recently, the complaints of breast cancer patients regarding their self-perceived memory loss following chemotherapy were often dismissed by many physicians. Now, a newly published prospective clinical research study from the M.D. Anderson Cancer Center suggests that physicians may have vastly underestimated the frequency, severity, and duration of cognitive dysfunction following standard breast cancer chemotherapy. This clinical study, which appears in the current issue of the journal Cancer, prospectively enrolled 42 women with newly diagnosed breast cancer. All of these women then underwent standardized neuropsychological evaluation before, during, and after chemotherapy. Importantly, this study not only tested these breast cancer patients in the early period after they completed their chemotherapy, but also one year after their chemotherapy had ended. The findings from this small study strikingly illustrate just how common, and how enduring, memory loss and other forms of cognitive dysfunction are following chemotherapy for breast cancer. Prior to beginning chemotherapy, 21 percent of these patients had some detectable degree of cognitive dysfunction. By the end of their chemotherapy treatments, a whopping 65 percent of these 42 patients displayed measurable declines in memory function, organizational ability, and cognitive processing speed. One year later, 61 percent of these women continued to display measurable declines in cognitive function. Worse yet, among this group of women with persistent cognitive dysfunction one year after completion of their chemotherapy, 71 percent continued to display progressively worsening of cognitive function when compared to their level of function immediately after finishing chemotherapy. Finally, the remaining 29 percent of this group of women with long-term evidence of cognitive dysfunction actually displayed a delayed-onset of cognitive decline when they were tested one year after chemotherapy (i.e., when compared to the results of their neuropsychological testing immediately after chemotherapy). Although this clinical research study enrolled a small cohort of patients, its prospective nature, and its use of validated neuropsychological tests, make it a powerful research study for its size. The findings of this study also fit well with previous laboratory research studies that have shown both acute and delayed changes in the actual structure of the brains of animals treated, proportionately, with the same chemotherapy drugs commonly used to treat breast cancer in humans. Whether or not the significant declines in cognitive function that were observed, one year after chemotherapy in the 61 percent of women who participated in this study, will eventually stabilize, improve or worsen is unknown at this time. Longer follow-up of these 42 breast cancer patients will have to be performed to answer this important question. However, this small prospective study clearly indicates that the majority of women who undergo standard chemotherapy for breast cancer appear to experience significant and prolonged declines in their level of cognitive function, including memory loss, decreased organizational skills, and a general slowing of their cognitive processing speed, and that these adverse changes persist for at least a year after completion of chemotherapy. The findings of this study should spur additional research into the precise cause(s) of this chemotherapy-associated impairment in cognitive function, as well as strategies to reduce the severity and duration of these adverse health effects following chemotherapy for breast cancer. Meanwhile, it is important for me to stress that chemotherapy unquestionably extends survival, and saves lives, among women who are appropriately advised to undergo such treatment for breast cancer. In my opinion, no patient should read this column, and then go on to refuse chemotherapy that has been appropriately recommended because of the findings of this clinical research study.
To learn more about the prevention, screening, diagnosis and treatment of breast cancer, look for the publication of my new landmark evidence-based book, “A Cancer Prevention Guide for the Human Race,” in the summer of this year.
Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity Dr. Wascher is an oncologic surgeon, a professor of surgery, a cancer researcher, an oncology consultant, and a widely published author For a different perspective on Dr. Wascher, please click on the following YouTube link: http://www.youtube.com/watch?v=7-Tdv7XW0qg I and the staff of Weekly Health Update would like to take this opportunity to thank the nearly 120,000 new and returning readers who visited our premier global health information website last month. As always, we enjoy receiving your stimulating feedback and questions, and I will continue to try and personally answer as many of your inquiries as I possibly can. In view of the extreme devastation and human misery brought about in Haiti and Chile by the recent earthquakes, Weekly Health Update asks our tens of thousands of caring readers to give generously to established charities that are currently working in those countries to assist the injured, the ill, and the homeless. There are many such legitimate charities, including the following two: http://www.imcworldwide.org/haiti |
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Breast Cancer, Physical Therapy & Lymphedema
January 17, 2010 by admin
Filed under Breast Cancer
Welcome to Weekly Health Update“A critical weekly review of important new research findings for health-conscious readers”
BREAST CANCER, PHYSICAL THERAPY &
LYMPHEDEMA
Arm lymphedema, or chronic swelling of the arm, occurs in 10 to 30 percent of women following treatment for breast cancer. When the lymphatic drainage network in the arm and hand has been disrupted by the surgical removal of axillary (armpit) lymph nodes, or by radiation therapy to the axilla (or, sometimes, following both types of treatment), the delicate network of lymphatic vessels that return excess tissue fluid back to the heart can become obstructed. This lymphatic obstruction can then result in chronic swelling of the hand and arm. Patients with significant lymphedema of the arm following breast cancer treatment may experience considerable swelling (edema), heaviness, stiffness and discomfort of the affected hand and arm. Unfortunately, there are no known effective methods available to prevent lymphedema, and once significant lymphedema does develop, compression sleeves and soft tissue massage are the primary treatment modalities currently available. Unfortunately, currently available lymphedema treatments are often not highly effective for many patients, and there is no known cure for lymphedema once it develops. Now, a newly published research study, in the British Medical Journal, suggests that physical therapy, when initiated early after breast cancer surgery, can significantly decrease the risk of arm and hand lymphedema. In this prospective randomized clinical research study, 120 women who underwent removal of their axillary lymph nodes for breast cancer were randomized to one of two groups. Women assigned to the experimental group underwent physical therapy 3 times per week, for a total of 3 weeks. Physical therapy techniques used in this group included manual lymph drainage and soft tissue massage techniques, as well as progressive shoulder exercises. Both groups of women also underwent the same lymphedema management educational course, but the control group of women did not receive any physical therapy interventions. Among the 116 women who completed at least one year of follow-up, 18 women (16 percent) went on to develop lymphedema. Fourteen of the women who developed lymphedema were in the control group, while the remaining 4 women were in the experimental group. Thus, in this clinical study, early physical therapy following axillary lymph node dissection (ALND) was associated with a very significant 72 percent reduction in the risk of developing lymphedema, at least within the first year following breast cancer surgery. Whether or not the use of early postoperative physical therapy can reduce the incidence of arm lymphedema over periods longer than one year is unknown at this time, and additional follow-up of the patients who participated in this clinical research study will be required to answer this very important question. However, this is one of the very few studies available that suggests a role for physical therapy in the actual prevention of arm and hand lymphedema following ALND for breast cancer. If additional, mature follow-up of these patients confirms a long-term benefit from early postoperative physical therapy in preventing arm lymphedema, then a strong case could be made for the routine use of early physical therapy in women who undergo ALND, and perhaps, as well, women who undergo sentinel lymph node biopsy with subsequent radiation therapy to the breast and armpit (axilla) area.
For additional information and resources related to cancer-associated lymphedema, please click on the links below: http://www.cancersupportivecare.com/Abstracts/asbdpbtps.html http://meeting.ascopubs.org/cgi/content/abstract/23/16_suppl/8185 http://www.annalssurgicaloncology.org/cgi/content/abstract/15/7/1996 http://www.cancerlynx.com/sln.html http://doctorwascher.com/Archives/11-23-08.htm http://doctorwascher.com/Archives/8-16-09.htm
Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity Dr. Wascher is an oncologic surgeon, a professor of surgery, a cancer researcher, an oncology consultant, and a widely published author For a somewhat lighter perspective on Dr. Wascher, please click on the following YouTube link: http://www.youtube.com/watch?v=7-Tdv7XW0qg
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Soy Isoflavones Reduce Breast Cancer Recurrence Risk
December 13, 2009 by admin
Filed under Breast Cancer, Cancer, Cancer Prevention, Isoflavones, Nutrition, Soy, diet, health
Welcome to Weekly Health Update“A critical weekly review of important new research findings for health-conscious readers”
SOY ISOFLAVONES REDUCE BREAST CANCER
RECURRENCE RISK
Regular readers of this column are already aware of the controversy surrounding soy isoflavone intake and breast cancer risk. As happens frequently in clinical research (unfortunately), contradictory research findings have made it difficult to understand the true relationship between dietary soy intake and breast cancer risk (if one exists). There is, for example, both laboratory and clinical data suggesting that a diet rich in soybean-derived products may be associated with a lower risk of developing breast cancer. At the same time, because genistein and other dietary isoflavones are known to weakly mimic the effects of estrogen, there has been some concern that a diet rich in isoflavone “phytoestrogens” may increase both the risk of developing a new breast cancer and the risk of developing a recurrence of a previous breast cancer. (In fact, there is data from laboratory research studies showing that genistein can indeed fuel the growth of human breast cancer cells growing in culture dishes, when exposed to high concentrations of this soy-derived isoflavone.)
A growing body of public health research, primarily from Asian countries where tofu and other soy-based foods are frequently consumed, appears to link increased soy consumption with a decreased lifetime breast cancer risk, particularly when soy-based foods are consumed during adolescence, during the time when development of the female breast is most active (Soy & Breast Cancer Risk). (Interestingly, there is also recent research suggesting that soy products might also reduce the risk of prostate cancer, which is another hormonally driven cancer: Genistein & Prostate Cancer Cells, Dietary Soy & Prostate Cancer Risk.)
Although epidemiological research is, increasingly, suggesting that a diet rich in soybean-derived foods might lower a woman’s lifetime risk of developing breast cancer, many breast cancer experts have remained apprehensive regarding dietary isoflavone intake in women with a prior history of breast cancer, in view of the estrogen-like effects of these “phytoestrogens.” As I have already noted, there is considerable research data available to suggest that soy-derived isoflavones can, at least under certain laboratory conditions, stimulate estrogen-sensitive breast cancer cells to grow and divide. These research findings have left many oncologists feeling uncomfortable in recommending soy-based foods to their breast cancer patients. Now, a newly publish public health study in the Journal of the American Medical Association suggests that soy-based foods may actually reduce the risk of breast cancer recurrence, and death due to any cause, in women who have previously been diagnosed with this very common form of cancer.
In this study, which was performed in Shanghai, China, 5,042 female breast cancer survivors (ages 20 to 75 years) were followed for an average of almost 4 years. All of these patient volunteers underwent detailed surveys regarding their lifestyle habits, including their diets. These patients, who were originally diagnosed with breast cancer between 2002 and 2006, were surveyed at 6, 18, 36 and 60 months following their original diagnosis with breast cancer.
The results of this study indicate that the breast cancer survivors who consumed the greatest amount of soy-based foods in their daily diets were 32 percent less likely to experience a recurrence of their breast cancer when compared to the women who consumed the least amount of soy-based isoflavones. Moreover, the women who consumed the greatest amount of soy were also 29 percent less likely to die, from any cause, when compared to the women who consumed the least amount of soy-derived foods.
A particularly interesting and unexpected finding of this study was that both women with estrogen sensitive breast cancers and women with tumors that were not sensitive to estrogen appeared to experience a significantly decreased risk of breast cancer recurrence if they frequently consumed soy products. Another important finding of this study was that women who were taking the estrogen-blocking cancer treatment drug tamoxifen also appeared to enjoy a reduced risk of breast cancer recurrence with higher levels of dietary soy intake. Additionally, the researchers noted that high levels of soy intake appeared to be about as effective in reducing the risk of breast cancer recurrence as the breast cancer prevention drug tamoxifen, alone.
The results of this very important study mirror the findings of the only other prospective clinical study that has looked at the impact of soy-based foods on breast cancer recurrence (the “Life After Cancer Epidemiology,” or “LACE,” study). The LACE study, which was performed in the United States, followed nearly 2,000 breast cancer survivors for, on average, more than 6 years. In the LACE study, women who were taking tamoxifen, and who also consumed the highest amount of soy-based dietary isoflavones, were 50 percent less likely to develop a recurrence of their breast cancer when compared to women who reported the lowest consumption of soy-derived foods.
As I have pointed out previously, epidemiological research studies based upon dietary surveys are susceptible to several types of bias which, in turn, can cause researchers to draw the wrong conclusions. In this case, however, there are now two large prospective cohort studies that have reached essentially the same conclusions (albeit with a rather limited duration of patient follow-up). Both studies strongly suggest that high levels of soy-based isoflavones in the diet may be able to significantly reduce the risk of breast cancer recurrence. Based upon the findings of this large Chinese study, the apparent cancer risk reduction effect associated with high levels of soy intake also appears to benefit premenopausal and postmenopausal women, as well as women who are taking the estrogen-blocking drug tamoxifen, women with estrogen-sensitive tumors, and women with (counter-intuitively) estrogen-resistant tumors.
In view of the limited duration of patient follow-up in both of these clinical breast cancer studies, as well as the limitations of survey-based epidemiological research in general, I would like to see updated data from both of these studies after at least 10 years of patient observation before I would be willing to tell my breast cancer patients that they should significantly increase their dietary soy intake. On the other hand, the rather compelling data presented by both of these clinical research studies will also make me less anxious when any of my breast cancer patients decide, of their own accord, to increase their intake of soy-derived isoflavones.
Note: Weekly Health Update is currently undergoing an extensive upgrade to better serve its tens of thousands of health-conscious readers around the world. Beginning in January 2010, newly archived columns will be available by selecting the “Archives” tab on the right side of your screen (all archived columns prior to January 2010 will continue to be available by selecting the “Archives 2007-2009” tab at the top of the screen.)
Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity Dr. Wascher is an oncologic surgeon, a professor of surgery, a cancer researcher, an oncology consultant, and a widely published author
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