Raloxifene - a better outlook for preventing breast cancer

Tamoxifen is a selective oestrogen receptor modulator (SERM). It has been used for over 30 years to treat both early and advanced breast cancer.

Raloxifene is a more recently developed SERM which is used for prevention and treatment of osteoporosis. Clinical trials have shown it may also have a role in reducing the risk of invasive breast cancer in postmenopausal women.More than 500,000 women in the United States are currently taking Raloxifene.

Victor G. Vogel, M.D., M.H.S., from Magee-Womens Hospital, University of Pittsburgh School of Medicine, and colleagues from The National Surgical Adjuvant Breast and Bowel Project (NSABP), have conducted a randomized clinical trial ( STAR / Study of Tamoxifen and Raloxifene ) at nearly 200 clinical centers in North America.Their results have been published in Journal of the American Medical Association (JAMA).

19,747 postmenopausal women (avg age 58.5 ) with an increased 5 year breast cancer risk selected nationwide in the USA formed the study group.

The study patients were randomized to receive oral tamoxifen (20 mg/day) or raloxifene (60 mg/day) over five years.

The results showed a total 163 cases of invasive breast cancer in women assigned to tamoxifen and 168 in those assigned to raloxifene (incidence = 4.30 per 1,000 / 4.41 per 1,000). Fewer cases of noninvasive breast cancer were found in the tamoxifen group (57 cases) than in the raloxifene group (80 cases)

Uterine cancer was detected in 36 cases of uterine cancer with tamoxifen and 23 with raloxifene; however, neither of these differences were found to be statistically significant.

No differences were found for other invasive cancer sites, for ischemic heart disease events, or for stroke.

Thromboembolic events (such as blood clots in the lung or deep veins) occurred less often in the raloxifene group and there were fewer cataracts and cataracts surgeries in that group.

The number of osteoporotic fractures in the two groups was similar.

There were no differences in the total number of deaths or in causes of death.

It appears that there wasa reluctance to prescribe tamoxifen because it is viewed as a toxic cancer drug. “In contrast, raloxifene is well known to the primary care community and is widely prescribed for the prevention and treatment of osteoporosis in postmenopausal women.

The researchers concluded : “This trial confirms the previously reported benefit of raloxifene in reducing the risk of invasive breast cancer and indicates that raloxifene is as active as tamoxifen in this regard. If raloxifene is approved by the Food and Drug Administration for the prevention of breast cancer, primary care physicians may be more willing, given their experience with raloxifene, to prescribe it for breast cancer chemoprevention than they have been to prescribe tamoxifen.”


JAMA. 2006;295:2727-2741. for the complete text.

In a related paper, Stephanie R. Land, Ph.D., from the University of Pittsburgh and colleagues from the NSABP STAR trial concentrated on studying differences in patient-reported outcomes, the QAL or quality of life, and symptoms in the STAR participants. The patient-reported outcomes were evaluated with standardized surveys using a 43-item symptom checklist.

They conclude "No significant differences existed between the tamoxifen and raloxifene groups in patient-reported outcomes for physical health, mental health, and depression, ....although the tamoxifen group reported better sexual function,”

“Although mean (average) symptom severity was low among these postmenopausal women, those in the tamoxifen group reported more gynecological problems, vasomotor symptoms, leg cramps, and bladder control problems, whereas women in the raloxifene group reported more musculoskeletal problems, dyspareunia (pain during sexual intercourse), and weight gain.”

“The NSABP’s STAR trial, with its large-scale symptom evaluation and well-powered quality of life substudy, provides a comprehensive, detailed view of the patient experience using raloxifene and tamoxifen. Both of these agents are indicated for prevention in large populations, so these results can be widely used as tools in decision making or in helping a woman anticipate and cope with the sequelae of her chosen agent,”

They point out that Raloxifine does not have regulatory approval for breast cancer prevention and assuming US regulatory approval of raloxifene to prevent breast cancer, physicians should discuss these 2 similar options carefully with their eligible and interested patients.


JAMA 2006;295 2742-2751 for the complete Text.


The National Cancer Institute reviewed the results of the STAR trial. They point out that Breast cancer is a critical public health problem: more than 212,000 women will be diagnosed with breast cancer in the United States this year and more than 30,000 will die of the disease.

An article April 18, 2006 • Volume 3 / Number 16 " STAR Results: Raloxifene as Effective as Tamoxifen, Better Safety Profile" conveys their views ..

"The long-awaited results of the largest breast cancer chemoprevention trial ever conducted provide what its leaders say is excellent news: Regular use of the anti-osteoporosis drug raloxifene (Evista) works just as well as tamoxifen at reducing breast cancer risk in postmenopausal women at high risk, but appears less likely to cause some of the potentially dangerous side effects seen with tamoxifen use."

The STAR results, added Dr. Leslie Ford, associate director for clinical research in NCI's Division of Cancer Prevention, "have immediate implications for how women view their breast cancer risk and what they can do about it. They will make breast cancer prevention more of a reality for many women."

Because tamoxifen has long been used for cancer treatment, Dr. Ford notes, that may have raised flags in many clinicians' minds about using it to prevent cancer.

"I think primary care physicians, gynecologists, and internists were somewhat uncomfortable with tamoxifen, despite its extensive safety profile," she says. "But raloxifene has been used by gynecologists and family practice physicians for preventing osteoporosis, so they may be more comfortable prescribing it."

Eli Lilly issed a Statement on the results It is understood that they will apply to the FDA for approval for use of Evista (Raloxifine) for use in preventing breast cancer in post menopausal women.