More women should take anti-breast-cancer drugs, US officials say

US health officials are recommending women should take one of three medications to help reduce the risk of breast cancer in new national guidelines.

The updated guidelines, issued by the US Preventive Services Task Force (USPSTF), suggest that post-menopausal women who are at an increased risk for developing the disease take aromatase inhibitors (AIs).

Increased risk factors include older age, a genetic mutation and a family history of breast cancer. 

AIs lower estrogen levels in the body, which makes it harder for breast cancer cells to grow, and could decrease cancer risk by as much as 50 percent.  

The new recommendations, published on Tuesday in the Journal of the American Medical Association, say the medications aren’t prescribed or used often – but could be a new first line of defense against breast cancer. 

Among women, breast cancer death rates are higher than the rates for any other cancer, aside from lung cancer.  

One out of every eight American women will be diagnosed with breast cancer during her lifetime, according to the American Cancer Society.

Women are considered at an increased risk if they are older, have a family history of breast cancer, carry the BRCA gene mutation or have a history of chest radiation.

In 2019, it is estimated that more than 331,530 cases of invasive and non-invasive breast cancer will be diagnosed in women and nearly 42,000 will die. 

Breast cancer does also occur in men but the incidence rate is less than one percent.

Mammograms are currently the main form of early detection, but medications to reduce risk of breast cancer could ‘provide an additional prevention option’, the authors write. 

According to the USPSTF, between 10 and 30 percent of primary care doctors say they’ve ever prescribed risk-reducing medications and most say they’ve done so only a few times.

And a 2016 study found that just 16.3 percent of women at increased risk for breast cancer use these medications.

The task force reviewed 46 studies to reach its recommendation.

The studies show that, three types of medications – tamoxifen, raloxifene, and aromatase inhibitors – were associated with a lower incidence of invasive breast cancer.  

Tamoxifen and raloxifene were recommended in the 2013 guidelines, but the new guidelines include aromatase inhibitors on the list of medications.

Results from 10 randomized clinical trials showed that the three drugs lowered the risk of developing invasive estrogen receptor-positive breast cancer by about 50 percent.

The USPSTF recommended against using the medication in women who are not at an increased risk for breast cancer or in women who have a current or previous breast cancer diagnosis. 

However, the task force said the medications can come with side effects and each woman needs to be assessed individually to determine her risk factors. 

Side effects can include hot flashes, fatigue, headaches, nausea and mood swings. 

‘When deciding whether or not to offer medications, clinicians should carefully consider their patients’ risk factors for breast cancer and balance these against the potential harms from the medications,’ said USPSTF member Dr Carol Mangione in a news release earlier this year. 

‘These medications are not for everyone, and for women who are not at increased risk of breast cancer, the harms of these medications are likely to outweigh the benefits.