Today’s advice from the doctor suggests women get a mammogram every year starting as early as age 40. We will delve further into whether getting mammograms at this age benefits women and prevents breast cancer deaths.
Over the last several decades, the rates of women diagnosed with breast cancer has been going up. However, breast cancer deaths has remained steady at around 40,000 in the United States per year.
Mammograms can find breast cancer in its earliest stages. Sometimes a woman is diagnosed with stage 0 breast cancer, which means cancerous cells are found in her milk ducts. There has been plenty of questioning regarding whether mammography at age 40 is beneficial.
A number of early stage breast cancers may never metastasize and grow. So even if a mammogram finds stage 0 breast cancer, will treatment save a life or is it unnecessary?
On the other side of the equation are the women who have early stage cancer that does grow and finding it early keeps them safe. So the question remains: do mammograms at age 40 prevent breast cancer deaths?
Early stage breast cancer
Women with ductal carcinoma in situ (DCIS) or stage 0 breast cancer have seen a growth of a more invasive breast cancer. One study published in JAMA Oncology found a 3.3 percent mortality rate after 20 years among 108,196 women with DCIS.
This statistic can be compared to the 99 percent five-year survival rate of people who have cancer located only in the breast. The vast majority of women diagnosed with stage 0 or stage 1 breast cancer will survive five years into the future.
“The risk of death increases after a diagnosis of an ipsilateral second primary invasive breast cancer, but prevention of these recurrences by radiotherapy does not diminish breast cancer mortality at 10 years,” the researchers wrote.
Nonetheless, there is some evidence that some stage 0 breast cancers may not advance and metastasize. According to research published in Cancer Australia, statistics gathered from multiple studies show that, for every 1,000 women in Australia screened for breast cancer every two years from 50 to 74 years of age, as many as 21 breast cancers may be uncovered and treated that would not have led to health problems during a woman’s lifetime.
False positives and new recommendations for screening age
Another problem that many women may face with breast cancer screening is the rate of false positives. A woman has a 50 or 60 percent chance of having a false positive after 10 years of yearly mammograms.
The problem with false positives is the next step in breast cancer diagnostics. Women whose mammograms reveal a potential cancer have to undergo biopsies to check for the disease. False positives lead to these unnecessary tests.
Due to these concerns, a number of organizations have advised an increase in age for mammography screening. The United States Preventive Services Task Force now recommends mammography screening every two years for women aged 50 to 74 years old.
When it comes to screening for breast cancer at age 40, women are allowed to make an individual decision comparing the risks and benefits, says the US Preventive Services Task Force. The American Cancer Society has now recommended women to start annual mammography at age 45 while the American College of Obstetricians and Gynecologists still recommends women to begin screening at 40 years of age, according to CNN.
“The ACS endorses beginning annual screening mammography at age 45 years and transitioning to biennial screening at age 55 years, while retaining the option to continue annual screening, which some women may elect based on personal preference, clinical guidance, or both,” researchers from the American Cancer Society wrote in a paper published in JAMA.
“After caeful examination of the burden of disease among women aged 40 to 54 years, the guideline development group (GDG) concluded that the lesser, but not insignificant, burden of disease for women aged 40 to 44 years and the higher cumulative risk of adverse outcomes no longer warranted a direct recommendation to begin screening at age 40 years.”
Mammography saves lives and the data backs it up
Mammography has been found to have a huge benefit in terms of saving lives. The International Agency for Research on Cancer (IARC) found that breast cancer death rates declined by 35 percent in women 50 to 69 years of age who took part in regular screening, according to the report published in Cancer Australia.
The national BreastScreen Australia Evaluation also found at least a 21 percent decrease in breast cancer mortality among women age 50-69 years who took part in regular mammography.
While some screen-detected breast cancers such as DCIS won’t advance and cause problems during a woman’s lifetime, it is impossible to know exactly what type of cancers won’t grow at the point of diagnosis.
Why breast cancer screening at age 40 could save lives
While we know that mammography does save lives, the question still remains – does it help prevent breast cancer deaths among women in their 40s? One thing we know is that one in six breast cancers are found in women 40 to 49 years of age, according to the American College of Radiology (ACR).
This fact alone shows the importance of getting screened at age 40. The statistics show that 252,710 women are predicted to be diagnosed with breast cancer in 2017. This means that at least 42,118 women in their 40s could be diagnosed with the disease.
Mammography can help find this disease in more than 42,000 women in their 40s and essentially save their lives.
A woman who is diagnosed with DCIS does have the option to speak with her doctor and determine whether a less aggressive treatment approach is best. For example, the breast cancer patient Desiree Basila decided to go with a less intense approach after being diagnosed with stage 0 breast cancer, according to Time Magazine. Basila takes the drug tamoxifen to block estrogen and takes a twice-a-year mammography and MRI screening procedure.
Even though we do not know if an early stage cancer will advance, mammography starting at age 40 could very well save lives. Until we can create new technology that can determine whether someone’s breast cancer will advance, using mammography to save lives is our best bet.