Improvements In Breast Cancer Screening
With 35 million mammograms performed yearly for breast cancer screening, it is important to have a very accurate screening process. Almost 90% of lumps are discovered by breast self-examination (BSE) which should be performed weekly by women, however the biennial mammogram is now currently recommended by the U.S. Preventative Services Task Force between the ages of 50 to 74 in addition to the BSE, unless recommended by an individual’s private physician due to family history or abnormalities found on BSE.
The mammogram has been performed with analogue (film) x-rays where the breast is compressed between two x-ray plates to improve clarity by reducing the breast’s thickness, spread the tissue out, allow for a lower dose of radiation, hold the breast still and to increase the sharpness of the picture.
Five to 15% of screening mammograms will require more testing with additional mammograms, ultrasound, and even magnetic resonance imaging (MRI). A mammogram exposes a women to as much radiation as an average person receives from background radiation in the environment in about 3 months, but repeated mammograms multiply this exposure. Findings of persistent abnormalities are followed up with breast biopsies. There is about a 5 to 7% chance of having a false-positive finding in a woman’s lifetime from conventional screenings.
The mammogram’s accuracy has been improved by digital mammography, where the x-ray film is replaced by solid-state detectors similar to those found in digital cameras. Another improvement is computer-aided detection (CAD) which uses computer software to search for abnormal areas of density, mass, or calcification obtained from the conventional x-ray film mammogram or a digital mammogram.
The most advanced screening now being investigated is tomosynthesis or 3 dimensional breast imaging performed with multiple digital techniques. The x-ray and current digital mammograms are only 2 dimensional. Tomosynthesis is now being reviewed by the FDA for its higher sensitivity, lower false positives and reduced unnecessary repeated x-rays and 2 dimensional digital mammograms with their incumbent added radiation exposure with subsequent ultrasound and unnecessary breast biopsies.
If you are one of the seven to ten percent of women with a false positive mammogram, it can be a very stressful and worrisome part of your life. Even though only about 7 percent of women found to have a false positive mammogram will require a breast biopsy, some will ultimately be found to have cancer. Having the diagnosis of breast cancer delayed by outdated initial screening methods (ie. film mammograms and 2 dimensional digital mammograms) may allow the cancer to progress to an unacceptable stage. The scientific advancement to three dimensional mammograms is not only cutting edge, but could be life-saving.