Breast Cancer Incidence & Hormone Replacement Therapy Circumcision & the Risk of HPV & HIV Infection
By, Robert A. Wascher, MD, FACS
The information in this column is intended for informational purposes only, and does not constitute medical advice or recommendations by the author. Please consult with your physician before making any lifestyle or medication changes, or if you have any other concerns regarding your health.
BREAST CANCER INCIDENCE & HORMONE REPLACEMENT THERAPY In the years following the end of World War II, the number of breast cancer cases diagnosed each year began to climb in the United States, and they kept on climbing until, in 2003, a historic decline in the annual incidence of breast cancer suddenly appeared. One year earlier, another dramatic event related to breast cancer also occurred. A huge prospective, randomized, placebo-controlled hormone replacement therapy (HRT) clinical trial, the Women’s Health Initiative study, prematurely terminated the portion of the study evaluating combination HRT pills (the most common type of HRT medication prescribed throughout the world). The plug was pulled on this clinical study because a worrisome excess of breast cancers (as well as cases of cardiovascular disease) was observed among the women who were secretly randomized to receive HRT pills containing both estrogen-like and progesterone-like female hormones (estrogen-only HRT pills are reserved for women who have previously undergone hysterectomy, as this type of HRT is associated with an increased risk of uterine cancer). The preliminary results of this study’s adverse findings, published in 2002 in the Journal of the American Medical Association, identified a nearly 30 percent increase in the risk of breast cancer among the women who had been randomized to take combination HRT pills. Many of us in the cancer research and treatment community have been arguing, for decades, that the continuously rising incidence of breast cancer observed in the post-war United States has been due to, at least in part, the rising use of HRT medications. Even prior to the publication of the Women’s Health Initiative study’s adverse findings, there have been numerous clinical studies that have linked a woman’s lifetime exposure to female sex hormones to the risk of developing breast cancer. In fact, even decades-old epidemiological studies have, repeatedly, identified an early onset of menstrual periods and a late arrival of menopause as risk factors for breast cancer (these events mark the beginning and end of ovarian hormone production, respectively). More recently, large breast cancer prevention studies have confirmed that estrogen-blocking medications can reduce the risk of breast cancer by about 50 percent in women who are at high risk for this type of cancer. However, despite decades of clinical and scientific evidence linking HRT to breast cancer risk, it took the sobering results of the Women’s Health Initiative study to finally convince large numbers of women, and their physicians, that HRT increases the risk of breast cancer (and, contrary to the findings of less rigorous and much older epidemiological studies suggesting that HRT reduces the risk of cardiovascular disease in women, the opposite effect actually appears to be the case). Following widespread reporting of the negative findings of the Women’s Health Initiative study, new HRT prescriptions in the United States declined an average of 40 percent over the first three years following the publication of the study’s results. Several clinical studies over the past 5 years have compared HRT prescribing trends with the incidence of breast cancer in the United States. These studies have shown a significant decrease in the number of new HRT prescriptions filled each year since 2002, and when plotted on a graph, the curve of this decline in new HRT prescriptions matches up very nicely with the curve of the declining number of new breast cancer cases observed each year since 2003. And yet, a significant number of doubters still remain. Some have hypothesized that a small downturn in the number of women undergoing screening mammograms might explain the fewer cases of breast cancer that have been diagnosed each year since 2003. Others have come up with even less likely potential explanations, hoping to explain away the growing and already substantial research evidence linking HRT with an increased risk of breast cancer. However, two new breast cancer research updates further confirm the link between HRT and breast cancer risk. An update of a previous breast cancer incidence study, from the National Cancer Institute and the M.D. Anderson Cancer Center, has just been published online in the journal Breast Cancer Research & Treatment. In this study, the authors reviewed and analyzed the newly updated SEER (Surveillance Epidemiology & End Results) database, which is the national cancer statistics database maintained by the National Cancer Institute. When compared to the period between 2000 and 2002, significant declines in the number of new cases of breast cancer were observed between 2003 and 2005. Altogether, a 20 percent drop in the incidence of new breast cancer cases was observed during the period beginning in 2003 and ending in 2005, and this historic trend closely mirrors the results predicted by the 2002 Women’s Health Initiative study report. Moreover, nearly the entire decline in breast cancer cases was observed in postmenopausal women over the age of 50, and in breast cancers sensitive to estrogen, further linking this dramatic decrease in breast cancer incidence to decreased HRT use among women. The other dramatic breast cancer research update was announced at the world’s largest annual breast cancer research conference, the San Antonio Breast Cancer Symposium, less than two weeks ago. At this symposium, the researchers from the Women’s Health Initiative study provided an update on the women who participated in the combination HRT group. These updated results offer striking proof that combination HRT pills are associated with a significantly increased risk of developing breast cancer. Among the study volunteers who took combination HRT pills for an average of 5 years, their risk of breast cancer is now 100 percent greater than what is being observed among the women volunteers who were secretly randomized to receive identical placebo (sugar) pills. This means that the incidence of breast cancer among the women who received combination HRT pills is now fully twice as high as is being observed in the women who did not take HRT pills. I have, for almost two decades now, recommended against taking HRT medications. In 85 to 90 percent of women, the symptoms of menopause subside significantly within 2 to 3 years. Although they are not quite as effective as HRT drugs in relieving the symptoms of menopause, there are also a variety of prescription and non-prescription remedies available that can reduce the severity of the hot flashes, night sweats and irritability that often accompany the early phases of menopause. (I will have much more to say on the topic of breast cancer prevention in my forthcoming book, “A Cancer Prevention Guide for the Human Race.”) Today, in 2008, my recommendations against HRT drugs remain even more vigorous than ever before. CIRCUMCISION & THE RISK OF HPV & HIV INFECTION Male circumcision continues to be a hotly debated topic. The practice of circumcision, most commonly performed for religious or cultural reasons, has been ongoing for thousands of years. Recently, however, there has been a growing backlash against infant circumcision in the United States and, in fact, between 1971 and 1983, the American Academy of Pediatrics formally advocated against the practice. The Academy’s position against circumcision was modified in 1989, however, after new clinical research data was published suggesting that circumcision significantly decreased the risk of acquiring the human immunodeficiency virus (HIV). However, in view of the historically non-medical basis for circumcision, and due to an increasing sensitivity on the part of both parents and physicians towards the discomfort that infants may experience during circumcision, this procedure continues to be the subject of considerable debate. Three newly published studies in the Journal of Infectious Diseases add to the findings of previous studies suggesting that a potential clinical benefit may be associated with circumcision. Specifically, these new studies suggest that not only does male circumcision reduce the risk of acquiring HIV infection, but it may also significantly reduce the risk of infection with the human papilloma virus (HPV). Like HIV, HPV is a sexually transmitted virus, and several strains of the HPV virus are known to cause virtually all cases of cancer of the cervix in women, as well as many of the cases of cancers of the anal canal, oral cavity, and throat (in both men and women). Several HPV virus strains also cause genital warts in both men and women. While chronic infection with cancer-causing HPV strains produces precancerous changes in women that can usually be detected during Pap smears, most infected males are asymptomatic. The FDA recently approved a human HPV vaccine, Gardasil, which provides protection against 4 strains of the HPV virus. Although not all cancer-causing strains of HPV are covered by Gardasil, the vaccine does provide protection against the HPV strains that, together, account for about 70 percent of all cervical cancer cases, and against more than 90 percent of all HPV-associated cases of genital warts. Because the vaccine is quite expensive, and because the vast majority of cancers caused by HPV occur in women, Gardasil is approved for use only in girls and young women between the ages of 9 and 26 years. The three new studies presented in the Journal of Infectious Diseases compared the incidence of HPV and HIV infections in sexually active men with and without a prior history of circumcision. One of these studies prospectively assessed the effects of adult circumcision in young African men, and after 21 months of follow-up, the incidence of HPV infection was observed to be 34 percent lower in the men who had been randomized to undergo circumcision when compared to the men who did not draw the “circumcision card.” The second clinical study was performed in the United States, and evaluated the incidence of HPV infection among circumcised and uncircumcised men. Among the 16 percent of men who had previously been circumcised, the incidence of HPV infection, after adjusting for a number of behavioral and demographic variables, the authors of this second study identified a 53 percent lower risk of HPV infection in the circumcised men when compared to the uncircumcised men. In an accompanying editorial, both of these studies were criticized due to inherent weaknesses in both methodology and analysis, although the editor acknowledged that there may well be a protective effect of circumcision against HPV infection in males. As males act as both reservoirs and vectors in the transmission of HPV, the possibility that circumcision may decrease the incidence of HPV infection in men is intriguing. As prior studies have produced conflicting results regarding the protective effect, if any, of circumcision against HPV infection in men, we must await the results of two large prospective male circumcision trials ongoing in Africa before circumcision can be advocated for the purpose of reducing the incidence of HPV infections. A third study in the Journal of Infectious Diseases adds to the already substantial body of research data confirming that male circumcision decreases the risk of HIV infection. In this third study, also performed in Africa, male circumcision reduced the risk of HIV infection in heterosexual African males known to be exposed to the virus by almost 50 percent, which is comparable to the findings of multiple prior studies that have looked at the impact of circumcision on HIV infection risk. Taken together, these three studies add important information regarding the potential protective effects of circumcision against infections by the HPV and HIV viruses. While the jury is still out with respect to circumcision and the risk of HPV infection, the data showing that circumcision cuts the risk of HIV infection in half is quite robust. Because of these findings, the World Health Organization now advocates on behalf of male circumcision as part of a comprehensive strategy to prevent HIV infections. However, no research study has ever suggested that male circumcision can protect men (or women) against all cases of HIV infection, and so even if you are circumcised, you still need to adhere to established safe sex practices to protect yourself and your partner from infections with HIV, HPV and other sexually transmitted diseases.
Dr. Wascher is an oncologic surgeon, professor of surgery, widely published author, and the Director of the Division of Surgical Oncology at Newark Beth Israel Medical Center:http://www.sbhcs.com/hospitals/newark_beth_israel/mservices/oncology/surgical.ht
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Copyright 2008. Robert A. Wascher, MD, FACS. All rights reserved.
Dr. Wascher's Archives:
10-26-2008: Smoking & Quality of Life
10-19-2008: Agent Orange & Prostate Cancer10-12-2008: Pomegranate Juice & Prostate Cancer10-5-2008: Central Obesity & Dementia; Diet, Vitamin D, Calcium, & Colon Cancer
9-21-2008: Does Tylenol® (Acetaminophen) Cause Asthma?
4-27-2008: Stents vs. Bypass Surgery for Coronary Artery Disease; The “DASH” Hypertension Diet & Cardiovascular Disease Prevention; Testosterone Therapy for Women with Decreased Sexual Desire & Function
4-6-2008: Human Papilloma Virus (HPV), Pap Smear Results & Cervical Cancer; Human Papilloma Virus (HPV) Infection & Oral Cancer; Hormone Replacement Therapy (HRT) & the Risk of Gastroesophageal Reflux Disorder (GERD)
12-16-2007: Honey vs. Dextromethorphan vs. No Treatment for Kids with Night-Time Cough, Acupuncture & Hot Flashes in Women with Breast Cancer, Physical Activity & the Risk of Death, Mediterranean Diet & Mortality