What is the reason for the PROSPECTS tomosynthesis study?
The results of the study will be used to inform the NHS Breast Screening Programme whether, and how, to implement tomosynthesis for routine screening.
What is breast tomosynthesis?
Breast tomosynthesis, or 3D mammography, is a technique using x-rays to produce a three-dimensional picture of the breast. It results in the production of layers through the breast which can be viewed as individual pictures. This often clarifies whether a finding is a true abnormality or an overlap of normal structures. This can result in the visualization of abnormalities that would be hard or impossible to see otherwise. Standard, or 2D, mammograms consist of one picture of the breast in each position, as opposed to many layers. Overlapping breast tissue can make the 2D images difficult to interpret.
What should I expect if I have 3D mammography?
3D mammography complements standard 2D mammography and is performed at the same time using the same equipment. There is no additional compression required, and it only takes a few more seconds longer for each view.
What are the possible benefits of tomosynthesis?
There are thought to be three main benefits of breast tomosynthesis:
- Reduced call-backs (or ‘false alarms’) reducing anxiety for women
- Better visualization (or ‘clearer picture’) of possible abnormalities on the mammogram
- Increased sensitivity by minimising the effect of overlapping breast tissue
Tomosynthesis can help the ‘film readers’ (people whose job involves looking at the scans) rule out abnormalities that may looked suspicious on a 2D mammography scan. Which reduces ladies being called back for more investigations and therefore reducing anxiety for women. Sensitivity of a scan refers to whether the scan has a high probability of picking up the correct diagnosis, it is known that 3D tomosynthesis scans have an increased sensitivity.
Can I choose to have the 3D tomosynthesis scan instead of the 2D mammogram scan?
No unfortunately not, by participating in the study you have a 50% chance of receiving the 3D tomosynthesis scan along with the 2D scan, rather than the 2D scan on its own. This is because the study is what is called a ‘randomised’ study meaning that a computer chooses randomly which group a participant will be in. This kind of study is the best way to compare the two groups so that at the end of the study the results are clear.
Is the radiation dose higher in the 3D tomosynthesis group of the study?
The dose of radiation is slightly higher for a 3D mammogram than with a 2D digital mammogram, the risk is considered very low but not zero. To put the risk in simpler terms, the amount of additional radiation that you would receive from the extra 3D imaging is approximately equivalent to three months of the natural background radiation that we all receive in everyday life. This is also the same as the radiation exposure of flying 1000 miles on a plane.
How long is the study, will I be told the results?
The study is over 4 years. The results of the study will be circulated to the public via relevant charities and websites.
Can I add a 3D mammogram on to a 2D mammogram after my scan if I change my mind?
No, the 3D images must be acquired at the same time as the 2D images. The same machine is used and the lady receiving the scan stays in the same position, with no additional compression required. The 3D images will take a few more seconds longer to acquire.
Does tomosynthesis mean I won’t be called back for further views?
Tomosynthesis can help film readers to rule out abnormalities that may look suspicious on 2D mammography. There is still a chance that some women may need additional mammographic views or ultrasound and be found not to have cancer.