HITCH
YOUR WAGON TO A SHINING STAR
(Study
of Tamoxifen And Raloxifene)
| HITCH
YOUR WAGON TO A SHINING STAR
|
 If you are a postmenopausal woman with breast cancer in your family, or you think you may be at high risk for the disease, you may want to do more than gaze wistfully at the night sky and wish on a lucky star. You just might want to make history - and lessen your personal risk - as part of one of the largest cancer prevention trials ever conducted. Breast cancer is still the most common type of cancer diagnosed in women living in North America. And it is still a particularly deadly one. But this is one clinical trial that will not leave you wondering whether you've been given a placebo or a powerful test drug. Every one of the potential 22,000 enrollees will have the opportunity to test one of two drugs for a five-year period. Enrollees are then followed for an additional two years. Tamoxifen (trade name Nolvadex) has been used to treat women with breast cancer for 30 years and was approved by the FDA in October 1998 to prevent the disease in healthy women at increased risk. The FDA took this action after more than 13,000 women took part in the first ever Breast Cancer Prevention Trial (BCPT), sponsored by the National Surgical Adjuvant Breast and Bowel Project (NSABP). In this study, Tamoxifen was shown to reduce the incidence of breast cancer in high risk women by 49 percent. Another drug, Raloxifene, was approved after 7,000 women with osteoporosis participated in the Multiple Outcomes of Raloxifene Trial (MORE). In addition to the beneficial effect found on the bones, the data suggested that Raloxifene (brand name Avista) may also play a role in continued breast cancer risk reduction. However, the study was not statistically designed to answer this question. Thus, STAR, the study of Tamoxifen and Raloxifene, will compare how effective these two drugs are in averting breast cancer in high risk, postmenopausal women of all races and ethnic backgrounds who have never had breast cancer. It will also determine which drug causes fewer side effects. Although New Jersey women are calling hotlines around the state to volunteer for the study, many are too young to participate. According to Deborah Toppmeyer, MD, co-principal investigator of STAR for The Cancer Institute of New Jersey (CINJ), only those who are 35 or older and are postmenopausal can be evaluated for acceptance into the trial. "Today we had three calls from women who want to do something about their breast cancer risk," she says. "But they are all premenopausal." Most callers have breast cancer in their families and many have read about the availability of testing for BRCA1 and 2 gene mutations, linked to the development of hereditary breast and ovarian cancers. Toppmeyer, a noted breast cancer specialist and director of the Cancer Risk Assessment and Counseling Program at CINJ, says that many women who have relatives with these cancers are worried about their personal risk. But in actuality, only 5 to 10 percent of breast and ovarian cancers are inherited. "Age is the greatest risk factor for breast cancer," she explains. "Most women over 60 would be eligible for the study." Entry into STAR is determined by figuring the individual's five-year probability of developing invasive breast cancer. A participant's risk must be equal to or greater than an average 60- to 64-year-old woman. An estimated 17 of every 1,000 U.S. women in that age group will develop breast cancer within five years. According to Judith Much, RN, nurse practitioner, who works closely with Toppmeyer in the risk assessment program and STAR, a 20-minute telephone interview will usually suffice for her to determine the caller's eligibility for the trial. If the volunteer seems to fit the criteria, Much invites her to attend an information session, and subsequently to fill out a one-page risk assessment questionnaire. Much says that other factors used in the original prevention trial and again in the STAR trial to determine increased risk of breast cancer include the woman's age, age when menses started, number of pregnancies, age at first pregnancy, number of breast biopsies, presence of lobular carcinoma in situ (LCIS), or atypical hyperplasia in the biopsy specimen, and history of breast cancer in the family in either mother, daughter or sister. To determine eligibility, women will complete a simple risk assessment form. The results will be discussed in detail with each potential participant. Toppmeyer says that although recruitment for the trial is on target, some eligible women may be reluctant to participate. There may be many reasons for this. Women must be weaned off hormone replacement therapy for three months before they can participate in STAR. Although both drugs have documented side effects, the cancer specialist says the perception of these risks is greatly exaggerated. The most common side effects of both drugs are hot flashes and vaginal dryness and itching. Serious side effects can occur with both drugs but are rare. Use of Tamoxifen is associated with a slightly increased risk for endometrial (uterine) cancer. Both drugs can cause blood clots either in the lung (pulmonary embolism) or in a major vein (deep vein thrombosis), but Toppmeyer says these risks need to be put in perspective. "In the original prevention trial, which compared Tamoxifen with placebo, there were 15 uterine cancers in approximately 7,000 women in the placebo group and 36 uterine cancers in the approximately 7,000 women taking Tamoxifen. There was one death from uterine cancer, but it was in the placebo group. All other endometrial cancers diagnosed in the treatment group were found at a very early stage and were successfully treated with surgery alone," says Toppmeyer. "The risk for blood clots is identical to that experienced by women who are on hormone replacement therapy." The physician also cautions that although there was no increased evidence of endometrial cancer with Raloxifene, there is not as much data available about the risks associated with this drug. It was studied for only five years, and on a much smaller group of women. Toppmeyer points out that some women who don't want to take medications will use "natural" therapies which have not yet been adequately studied and about which little is known. "Many women are using complementary and alternative medicines containing phytoestrogens, such as soy, licorice root and black cohosh," she says. "Although 'natural,' many of these therapies may be fraught with side effects. But interestingly, some of these women are afraid to take Tamoxifen, which has been studied for more than 30 years." The CINJ site - which is one of several in New Jersey - has so far signed up 15 women for this trial. "Some women come to the education session, but decide it's not for them," says Much."Anyone can attend an information session. It doesn't obligate you to do anything more." Toppmeyer sees STAR as a wonderful opportunity for women concerned about breast cancer, which is probably most women in New Jersey. "Breast cancer is a disease that we have a great chance of curing if we can catch it early. Now we have a great chance of preventing it for many women," she says. For those who would like to give their daughters a generous and enduring gift of inestimable value, there may be no time like the moment to help launch this very promising STAR. For more information, call 732-235-7212. In south Jersey, the Cooper Cancer Institute is participating. Call 856-325-6754. |
The magazine of the University of Medicine and Dentistry of New Jersey |
