Breast cancer tomosynthesis, also known as 3D mammography or digital breast tomosynthesis (DBT), is an advanced imaging technique. It provides a more detailed view of breast tissue compared to traditional methods, aiming to improve screening accuracy and aid in early abnormality detection.
The Science Behind 3D Mammography
Digital breast tomosynthesis operates on the principle of three-dimensional imaging. During the procedure, the X-ray tube moves in a small arc over the compressed breast, capturing multiple low-dose X-ray images from various angles. These individual images are then digitized and sent to a computer system.
The computer utilizes specialized algorithms to reconstruct these images into a detailed three-dimensional view of the breast tissue. This creates thin, high-resolution “slices,” allowing radiologists to examine the breast layer by layer, much like flipping through the pages of a book. This layered approach helps overcome a common limitation of 2D mammography: the superimposition of breast tissues, which can obscure abnormalities or create false alarms.
Enhanced Detection and Diagnostic Clarity
Tomosynthesis offers improvements in breast cancer detection and diagnosis compared to traditional 2D mammography. Its layered view of breast tissue helps detect smaller cancers, particularly within dense breast tissue where overlapping structures can hide lesions in 2D images. Tomosynthesis increases the detection of invasive cancers. The increased sensitivity for architectural distortion also improves the diagnosis of invasive lobular cancers.
This advanced imaging also plays a role in reducing unnecessary callbacks for additional imaging, often referred to as recall rates. By providing clearer, more comprehensive images, radiologists can better differentiate between benign structures, such as normal overlapping breast tissue, and actual abnormalities. This leads to fewer false-positive results, meaning fewer instances where a potential issue is flagged that later turns out to be non-cancerous. The improved diagnostic confidence can also result in a higher percentage of biopsies yielding positive results.
What to Expect During a Tomosynthesis Exam
The patient experience during a breast tomosynthesis exam is similar to that of a standard 2D mammogram. You will be asked to remove clothing and jewelry from the waist up and may be provided with a gown. Your breast will be positioned on a flat support and gently compressed between two plates. This compression is necessary to spread out the tissue for clearer images and to allow for a lower radiation dose.
While compression can cause mild discomfort or pressure, it is usually brief. The main difference you might notice is the X-ray tube moving in an arc over your breast as it captures multiple images from different angles. This process takes only a few seconds per breast, and you may be asked to hold your breath briefly to minimize movement and prevent blurred images. The entire appointment generally lasts around 15 to 30 minutes.
Is 3D Mammography Right For You?
Considering a tomosynthesis exam involves discussing several factors with your healthcare provider. Breast density is a consideration, as 3D mammography is beneficial for individuals with dense breast tissue. Dense breasts can make it challenging to detect small cancers with traditional mammograms because both dense tissue and cancerous lesions appear white on standard images.
Personal risk factors for breast cancer, such as family history or previous biopsies indicating atypical cells, also influence recommendations for 3D mammography. Regarding radiation exposure, a 3D mammogram involves a slightly higher dose than a 2D mammogram, typically ranging from 0.5 to 1 mSv, compared to 0.4–0.5 mSv for 2D. However, this amount is considered minimal and remains within safe limits, comparable to a few months of natural background radiation exposure. The benefits of enhanced detection and reduced false positives generally outweigh this minimal radiation risk. Consulting with a doctor is important to determine the most appropriate screening method based on your individual health profile.