Medroxyprogesterone Acetate

An older form of hormone therapy taken to ease the symptoms of menopause could increase the risk of ovarian cancer, according to results released Thursday from two studies involving tens of thousands of women. Another hormonal regimen didnt seem to carry this same risk, researchers found.The results should help settle debate over the relative risk of cancer associated with estrogen- and progestin-based hormonal therapy. Still, researchers noted, the absolute risk of ovarian cancer associated with either regimen is low.Before these randomized, placebo-controlled clinical trials, observational studies examining the influence of estrogen plus progestin on ovarian and endometrial cancers gave mixed results, said Rowan Chlebowski, of the Lundquist Institute in California, in a statement on the findings. Our study provides the only long-term information from a randomized clinical trial on two common cancers in postmenopausal women for two of the most commonly used medications.Part of the Womens Health Initiative that began in 1991, the studies ran between 1993 and 1998 and enrolled more than 27,000 women aged 50 to 79 years from across the U.S. The findings, which stem from a 20-year follow-up analysis, will be presented at the American Society of Clinical Oncologys annual meeting, being held in Chicago from May 31 to June 4.For postmenopausal women, hormone therapy has long been used to help manage hot flashes and sleep disturbances. During the time of the studies, the standard option for women who had had a hysterectomy, or their uteruses removed, was conjugated equine estrogen, or CEE. Women who still had a uterus often received CEE plus medroxyprogesterone acetate, or MPA.The WHI studies randomized women without a uterus to either CEE or a placebo, and those who had a uterus to receive CEE plus MPA or a placebo.Results show that CEE was associated with a higher risk of developing ovarian cancer compared to placebo, with 35 cases in the hormone therapy group versus 17 in the placebo group. The risk of dying from ovarian cancer was almost three times higher with among CEE-treated women than in those given placebo.But among women with uteruses who took CEE plus MPA, there was no statistically significant increase in the risk of developing ovarian cancer, or in dying from it. Notably, women on this regimen had a 28% lower risk of developing uterine cancer, researchers found.While this new information is an important part of patient counseling and education, given the low numbers, it should not necessarily impact a woman's decision to take menopausal hormone therapy for symptomatic relief of menopausal symptoms, said Eleonora Teplinsky, a physician at Valley Mount Sinai Comprehensive Cancer Care, in a statement provided by ASCO.CEE was for years a common menopausal treatment. But its use declined following prior WHI findings on associated heart risks that led to Food and Drug Administration warnings.Hormonal therapy is not currently recommended for all postmenopausal women. Groups like the American Cancer Society have previously flagged ovarian cancer risk, while the FDA has highlighted the risk of endometrial cancer. The regulator advises women who do take hormonal therapy for menopausal symptoms to use the lowest dose for as short a time as possible.However, WHI researchers noted that ovarian cancer is not currently incorporated as a risk in prescribing guidelines for menopausal hormone therapy. They also suggested that their findings prompt reconsideration of advice around estrogen-only use in ovarian cancer survivors.Some drugmakers, meanwhile, are developing non-hormonal medications that could become an alternative to hormone therapy for treating vasomotor symptoms. '