5. The Bad Side of Screening Mammograms.
Fast-growing or aggressive cancers may have already spread to other parts of the body, regardless of whether or not a screening mammogram has been taken. There also have been false-negative results, when mammograms appear normal even though breast cancer is present. Screening mammograms miss up to 20% of breast cancers that are present at the time of screening, mainly caused by breast density (dense and fatty tissue in the breast). Younger women are more likely to have denser breasts.
False-positive results also have occurred when radiologists conclude that the mammogram is abnormal but no cancer is actually present. Again, this is more common in younger women. All abnormal mammograms should be followed up with additional testing: diagnostic mammograms, ultrasound, and/or biopsy. There’s also the risk of radiation exposure, as with all x-rays. And repeated x-rays have the potential to cause cancer. The radiation exposure of resulting from mammograms is very low; thus, the benefits tend to outweigh the risk.