Despite it being the most common cancer among women, death rates due to breast cancer continue to fall in the US, except for African Americans, where the rate remains steady.

A new American Cancer Society report, Breast Cancer Facts & Figures 2009-2010, released on 30 September, shows that breast cancer deaths have been falling in the US since the early 1990s, with the biggest drops in women under 50.

Researchers suggest the steady rate of decline is probably due to earlier detection through screening and improvements in treatments.

Chief executive officer of the American Cancer Society, Dr John R Seffrin told the media that:

“The steady drop in the breast cancer death rate means that this year alone, about 15,000 breast cancer deaths were avoided that would have occurred had rates not begun to drop.”

“Since the early 1990s, that decline adds up to more than 130,000 grandmothers, mothers, and daughters who were alive, perhaps to celebrate another birthday, and even to go on to live a full, rich life,” he added.

However, while giving cause to celebrate, the report points out a stark contrast between whites and African Americans.

As of 2006, breast cancer death rates were 38 per cent higher in African American women than white women.

The report highlights possible reasons for the disparity. While white women have higher incidence rates of breast cancer than African American women, two things stand out as different between the two groups. One is that incidence of breast cancer in white women has fallen at a rate of 2 per cent per year since 1999, while they have stayed steady among African American women, and the other is that African American women are more likely to be diagnosed at a later stage, when the cancer is less treatable.

Researchers suggest the dramatic reduction in the number of women using postmenopausal hormone replacement therapy (HRT) following the results of the 2002 Women’s Health Initiative study that linked HRT to higher risk of breast cancer could account for some of the decline in breast cancer incidence.

The stable incidence rate among African American women may be partly because they were already low users of HRT, and use of screening like mammography has not gone up in this group.

The report also shows that the number of breast cancer survivors is growing, with figures from January 2006 giving a total of 2.5 million American women living with a history of the disease.

American Cancer Society national volunteer president Dr Elizabeth “Terry” TH Fontham, said:

“While there is much to celebrate in the fight against cancer, this report is also a strong reminder that far too many women still die of breast cancer and of the work yet to be done.”

“We need to make sure all women have access to information to help them reduce their risk and to resources to ensure early detection and the best possible treatment,” she added.

In a statement to the press, the American Cancer Society was keen to stress that some of the many positive things to emerge from cancer research is that we now know more than ever about the major risk factors for breast cancer, and that many of them are modifiable, including exercise and weight control.

The Society’s chief medical officer, Dr Otis W Brawley also highlighted the link between the drop in incidence of breast cancer and reduction in use of HRT, which he referred to as another modifiable risk factor, however, he warned that:

“While that is gratifying to see, we remain concerned about obesity’s potential to offset that drop, and lead to an increase in the incidence of breast cancer in the future.”

Another way to increase chances of survival is better and earlier screening and detection. Mammograms can find breast cancers earlier, when they are easier to treat and chances of survival are higher.

The American Cancer Society recommends women over 40 should have yearly mammograms and breast exams, while women at high risk, such as those who may be carrying the BRCA gene mutations, should talk to their doctors about getting an MRI as well, they said.

Here are some more steps the Society recommends for women to reduce their risk of getting breast cancer:

  • Eat a healthy diet and control your weight because being overweight and obese is a possible risk factor.
  • Exercise 30 minutes a day on 5 or more days a week (45 to 60 mins may be even better for reducing breast cancer risk).
  • Limit alcohol consumption to no more than 1 drink a day. Alcohol is clearly linked to increased risk of breast cancer.
  • Go and see your doctor if you notice any changes in your breasts or are worried about them at all.

— more info on the report

Source: American Cancer Society.

Written by: Catharine Paddock, PhD