Breast cancer drugs should be offered to healthy but high risk women, US panel concludes

BMJ 2013; 346 doi: (Published 18 April 2013) Cite this as: BMJ 2013;346:f2499
  1. Michael McCarthy
  1. 1Seattle

Physicians should offer to prescribe tamoxifen or raloxifene to women who are at a raised risk of breast cancer and have a low risk for the adverse side effects associated with these drugs, say draft recommendations drawn up by a US Preventive Services Task Force panel and released for public comment Tuesday.

The panel’s recommendations apply to asymptomatic women between the ages of 40 and 70 years without a prior diagnosis of breast cancer, ductal carcinoma in situ, or lobular carcinoma in situ.

The panel’s conclusion, which was based on a systematic review,1 was that the drugs, both selective estrogen receptor modulators, have been shown in randomized, controlled trials to reduce the risk of developing hormone receptor positive breast cancer.

For postmenopausal women at increased risk of breast cancer, the panel found that there was “adequate evidence” that treatment with tamoxifen or raloxifene “can significantly reduce the relative risk for invasive HR [hormone receptor]-positive breast cancer.”

The panel said, “Tamoxifen and raloxifene reduced the incidence of invasive breast cancer by 7 to 9 fewer events per 1000 women over 5 years, and tamoxifen reduced breast cancer incidence more than raloxifene.

“Tamoxifen also reduces the incidence of invasive breast cancer in premenopausal women who are at increased risk for breast cancer.”

Women who are considered to be at increased risk of breast cancer include older women; women who have a family history of breast or ovarian cancer, especially those with a first degree relative in whom onset of breast or ovarian cancer was before the age of 50; women with a history of atypical hyperplasia or other non-malignant high risk breast lesions; and women with extremely dense breast tissue.

The panel recommends that physicians use a formal risk assessment tool to gauge a woman’s risk of breast cancer, such as the US National Cancer Institute’s breast cancer risk assessment tool (

“In general, women with an estimated 5-year breast cancer risk of 3% or greater are more likely to benefit from tamoxifen or raloxifene, based on estimates in models,” the panel wrote.

For women who are not considered at a raised risk of breast cancer, the panel concluded “with moderate certainty” that the potential harms of tamoxifen and raloxifene outweighed their potential benefits in terms of breast cancer risk reduction.

Neither drug should be used in women who have a history of thromboembolic events, such as deep venous thrombosis, pulmonary embolus, stroke, or transient ischemic attack, the panel added.


Cite this as: BMJ 2013;346:f2499


  • A draft of the panel’s recommendations has been posted online for public comment ( Comments will be accepted until 13 May 2013.