No Evidence For Cut-Off Age for Breast Cancer Screening

There is no evidence supporting a clear cut-off age to stop breast cancer screening, according to a study presented at RSNA 2016.

Researchers from the University of California, San Francisco, sought to evaluate the relationship between patient age and screening mammography performance metrics in women who are 40 years old and older.

"All prior randomized, controlled trials excluded women older than 75, limiting available data to small observational studies," co-author Cindy S. Lee, MD, an assistant professor in residence at UCSF, said in a release. "There has been a lot of controversy, debate, and conversation regarding the different breast cancer screening guidelines, even among major national organizations, over the past few years."

Using data from the National Mammography Database, the researchers analyzed data from 6,980,054 screening mammograms of 3,416,075 women, which had been performed between January 2008 and December 2014 in 218 facilities across 39 states in the U.S. The women were sorted into patient groups by age in five-year intervals. Performance metrics calculated were cancer detection rate, recall rate, and positive predictive values for biopsy recommended (PPV2) and biopsy performed (PPV3).[[{"type":"media","view_mode":"media_crop","fid":"54408","attributes":{"alt":"Cindy S. Lee, MD","class":"media-image media-image-right","id":"media_crop_5390759160324","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"6812","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"height: 256px; width: 170px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"Cindy S. Lee, MD","typeof":"foaf:Image"}}]]

The results showed that a mean cancer detection rate of 3.65 per 1,000, a recall rate of 10%, PPV2 of 20%, and PPV3 of 28%. Based on increasing age, performance metrics demonstrate a gradual upward trend for cancer detection rate, PPV2 and PPV3, and downward trend in recall rate, until age 90.

"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,"  Lee said. "We know that the risk of breast cancer increases with age. With the uncertainty and controversy about what age to stop breast cancer screening, we addressed this gap in knowledge and have collected enough data to make a conclusion."