Mammography is the standard imaging
technique used for breast cancer screening worldwide. It reduces mortality by
20% across all age groups. Guidelines about the age to start the screening are
nearly similar across the globe but, since long debates are ongoing regarding
the age at which we can safely make a recommendation to stop screening.
In USA, women start routine mammography
screening in their 40s. Similar guidelines are put forward by Australia, where
biennial screening is advised for women aged 50 to 74 years and
In 2009, the United States Preventive
Services Task Force (USPSTF) released new guidelines which stated there was not
enough evidence to assess the balance of benefits and harms of screening
mammography in women aged 75 years or older.
Dr. Cindy S. Lee, M.D., assistant
professor in residence at the University of California, San Francisco said this
is because most RCTs exclude women more than 75 years of age, thereby data is
very sparse and limited to few observational studies.
Dr. Lee presented a paper at 102 annual
meeting of the Radiological Society of North America at Chicago on November 28.[1]
This is the largest ever study on screening mammography and using data from the
National Mammography Database Dr. Lee and her colleagues analyzed data from nearly 5.6 million screening mammograms performed over
a period of 7 years (2008 – 2014) across multiple locations in 31 US states.[2]
Women over
40 years of age were sorted into groups by age in 5 years’ interval for specific
age related analysis of the data. The researchers looked at age, ethnicity,
mammography results, cancer detection and biopsy results.
The mean
cancer detection rate from the study was 3.74 per 1,000 patients, with
increasing cancer detection trend as the age increases till 90 years.
Dr. Lee said" The continuing
increase of cancer detection rate and positive predictive values in women
between the ages of 75 and 90 does not provide evidence for age-based
mammography cessation."
It was also seen that as women get
older, the chances of cancer detection increase, the positive predictive value(PPV)
increase because of decrease in breast density.
ACS recommends to continue screening
as long as women is in good health.
Some 80 years old women are in very
good health, the life expectancy of healthy 75-year-old women is 13 years and
that of healthy 80 years is another 89 years.
The decision about when to stop screening
should be based on woman’s individual preference, her medical history and
general health.
Dr. Andrew Kaunitz said" In my
practice, many of the women in their mid-70s and older I see are active and
have life expectancies that exceed one decade. The majority of these patients
wish to continue screening mammograms, a decision I support."
The Science behind the new ACS Breast
Cancer Screening Guidelines.
