3D mammography is an FDA-approved, innovative, new technique for breast cancer screening. 3D mammography is more formally known as digital breast tomosynthesis, or DBT. This exam finds abnormalities that cannot be seen or felt by you or your doctor. Most of these abnormalities are not cancer, but they must be further investigated by a radiologist.
3D mammograms use low-dose X-rays to create a three-dimensional image of the breast. The scanner rotates partially around the breast and takes images from many different angles (typically 10 to 15). The breast must be compressed as it is with a conventional mammogram. Despite taking more images, 3D mammography does not require any more radiation than a conventional mammogram. After all images are taken, sophisticated computer programs assemble them into a three-dimensional representation of the breast. The radiologist can then view the breast tissue in narrow slices, similarly to CT scan images.
With conventional mammography, which is two-dimensional, overlapping tissue can mask suspicious areas. Because thin layers of breast tissue are viewed with 3D mammography, the overlap is removed, and abnormalities are much easier to recognize. Studies have shown improved tissue identification, improved tumor visualization and a lower recall rate for additional testing. Because of this, 3D mammography has the potential to improve on the accuracy of mammograms.
While conventional mammography continues to be the primary screening method for breast cancer, experts estimate that 3D mammography will replace it within 10 years. Large trials are currently being conducted to determine the feasibility. The results of one 3D mammography trial, reported in The Journal of the American Medical Association, confirm that it finds more invasive cancers and reduces unnecessary callbacks. Like conventional mammograms, 3D mammograms do not prevent breast cancer. They will help a doctor find cancer much earlier. 3D mammography can identify a lump up to two years before it will become large enough for you to feel it. By finding breast cancer early, a woman’s chances of survival are higher, and she may have more treatment options available to her. When breast cancer is found early, the five-year survival rate is greater than 95%. Additionally, finding breast cancer early enables more women to select treatment options that allow them to keep their breasts.
(photo: Louie Enriquez, MD, JD, breast radiologist)