Chemoprevention of breast cancer applies to only a few

Doctors say the current appeal is extremely limited, but experts say this approach is only the beginning of new cancer prevention.

By Victoria Stagg Elliott — Posted Oct. 25, 2004

Print  |   Email  |   Respond  |   Reprints  |   Like Facebook  |   Share Twitter  |   Tweet Linkedin

Asking a woman about her age and her breast cancer risk can pinpoint who fits into the small percentage for whom taking the drug tamoxifen for the primary prevention of breast cancer is a realistic option.

The drug is also only cost effective for those in their 40s who are at high risk of the disease, according to two studies published last month. The authors hope their findings will enable physicians to target the extensive discussion required before initiating chemoprevention of breast cancer to those who need it the most.

"I hope this saves doctors some time," said Russell Harris, MD, MPH, associate professor of medicine at the University of North Carolina at Chapel Hill School of Medicine. "It may help focus discussions where they need to go. Tamoxifen can prevent breast cancer, but it can do some bad things, too."

Dr. Harris's study, published in the Sept. 27 Archives of Internal Medicine, found that asking about breast cancer family history and previous breast biopsies was enough to exclude the majority of women from long, complicated talks about the risks and benefits of this type of breast cancer chemoprevention.

The other study, appearing in the September issue of Obstetrics & Gynecology, found that the drug was cost effective for women ages 40 to 50 who were at significant risk for breast cancer. It also could be cost effective for older women depending on their fear of breast cancer, level of risk and whether they had a uterus.

"We're saying almost the same thing," said Sam Cykert, MD, lead author on that paper and chief of the internal medicine program at Moses H. Cone Memorial Hospital in Greensboro, N.C. "For certain women, doctors ought to mention tamoxifen and have the talk."

But at least for now, the authors said, very few primary care physicians are sold on tamoxifen's benefits for primary prevention, and several doctors said these papers still did not sell them on the merits of offering this drug to their patients. The number of patients who would benefit is small, and the subset of those who would be willing to take it for years, particularly with the various side effects, is even smaller.

"I haven't been pushing it," said Julie Fagan, MD, associate professor of medicine at the University of Wisconsin women's health center in Madison. "Women who have breast cancer will put up with the side effects, but I haven't had a lot of people clamoring to take it primarily for breast cancer prevention. The benefits are pretty slim at this point unless they're extremely motivated."

Pinpointing the promise

Some who support the increased use of tamoxifen for primary prevention, however, said these papers were crucial work toward getting pharmacological primary prevention of cancer out of the specialist setting and into primary care -- where most believe it belongs. Specialists have long been familiar with tamoxifen and use it widely for secondary prevention, but they say it will not reach enough people to achieve its full promise until it becomes a part of general practice.

"A lot of this information has been out in the medical oncology literature," said Claudine Isaacs, MD, associate professor of medicine and oncology at Georgetown University in Washington, D.C. "But obviously, the group that it applies to and the people who need to think about talking to patients about this are the primary care physicians."

Experts argue that, although the number of women for whom tamoxifen is worth its risks is small, these women do benefit significantly.

They also say, as a result, that this concept makes it worthwhile for physicians to screen their patients to detect appropriate candidates for this drug therapy.

"There are relatively few women who would benefit from the drug, but for women who would benefit, it's a big benefit." said Jennifer Haas, MD, MPH, associate professor of internal medicine at Brigham and Women's Hospital in Boston. "To not screen women is a disservice."

Experts also acknowledged, though, that an urgent need continues for better methods to determine who will most benefit from this intervention.

"I get asked all the time: How many women do you need to treat in order to prevent one breast cancer?" said Lawrence Wickerham, MD, associate chair of the National Surgical Adjuvant Breast and Bowel Project which has run many of the tamoxifen trials. "The answer is two -- because it reduces the risk by 50%. The challenge is to find the right two."

Nonetheless, tamoxifen's supporters also recognize that while the drug has tentatively started the era of primary prevention of cancer, this era probably will not blossom until newer agents with fewer side effects come on the market. For example, the study in the Archives found that the drug would probably prevent only 6% to 8% of breast cancers if everyone eligible agreed to take it, a significant but not very large reduction.

"[Tamoxifen] is not the answer to breast cancer," Dr. Harris said. "It does mean that it's a promising approach. If we were able to come up with a pill like tamoxifen that didn't have the side effects and we could give it to a larger number of women, maybe we'd be on to something."

Most expect a big step in this direction with the release of the results of the Study of Tamoxifen and Raloxifene -- the STAR trial -- expected at the end of next year.

"If the STAR study shows definite benefit, that may change everything," Dr. Fagan said. "I think everyone's waiting for that before they go whole hog into chemoprevention."

Back to top


Tamoxifen: Targeting the talk

Objective: Two recent studies attempted to determine the characteristics of women who should be targeted for discussions about chemoprevention of breast cancer with tamoxifen.

Methods: Researchers who authored the study in the Archives of Internal Medicine surveyed more than 600 women who, in 2001, presented at 10 general internal medicine practices in North Carolina. A second study appearing in Obstetrics & Gynecology involved a cost-effectiveness analysis based on quality-of-life information collected from more than 100 women, financial data from the Breast Cancer Chemoprevention Trial and other published studies.

Results: Asking about family history and breast biopsies identified the less than 10% of women eligible to discuss tamoxifen. At most, the drug would prevent 6% to 8% of breast cancers. The use of tamoxifen led to a remaining life expectancy of 26.07 years, while those who were untreated had 25.97 years. The cost per quality-of-life year gained was $43,300. The drug was more cost effective for younger women without a uterus but who had a higher risk of breast cancer and an increased fear of the disease.

Conclusions: Only a small number of women in primary care practices are eligible to even discuss the drug, and a low number of cancers would actually be prevented. The drug is cost effective for women ages 40 to 50 who are at significant cancer risk. The challenge is to target discussions to those most appropriate.

Source: Archives of Internal Medicine, Sept. 27; Obstetrics & Gynecology, September

Back to top

External links

"Breast cancer risk in primary care: Implications for chemoprevention," abstract, Archives of Internal Medicine, Sept. 27 (link)

"Tamoxifen for breast cancer prevention: A framework for clinical decisions," abstract, Obstetrics & Gynecology, September (link)

National Surgical Adjuvant Breast and Bowel Project (link)

Back to top



Read story

Confronting bias against obese patients

Medical educators are starting to raise awareness about how weight-related stigma can impair patient-physician communication and the treatment of obesity. Read story

Read story


American Medical News is ceasing publication after 55 years of serving physicians by keeping them informed of their rapidly changing profession. Read story

Read story

Policing medical practice employees after work

Doctors can try to regulate staff actions outside the office, but they must watch what they try to stamp out and how they do it. Read story

Read story

Diabetes prevention: Set on a course for lifestyle change

The YMCA's evidence-based program is helping prediabetic patients eat right, get active and lose weight. Read story

Read story

Medicaid's muddled preventive care picture

The health system reform law promises no-cost coverage of a lengthy list of screenings and other prevention services, but some beneficiaries still might miss out. Read story

Read story

How to get tax breaks for your medical practice

Federal, state and local governments offer doctors incentives because practices are recognized as economic engines. But physicians must know how and where to find them. Read story

Read story

Advance pay ACOs: A down payment on Medicare's future

Accountable care organizations that pay doctors up-front bring practice improvements, but it's unclear yet if program actuaries will see a return on investment. Read story

Read story

Physician liability: Your team, your legal risk

When health care team members drop the ball, it's often doctors who end up in court. How can physicians improve such care and avoid risks? Read story

  • Stay informed
  • Twitter
  • Facebook
  • RSS
  • LinkedIn