Behind The Screen What to know about 3D mammograms

Early detection is always key when it comes to cancer. Here, breast surgeon DR GEORGETTE CHAN shares the latest advances in breast cancer screening, and how 3D mammography might benefit you.

While a breast examination itself can’t prevent breast cancer, early detection can mean earlier treatment, which ultimately means a better chance of survival. In fact, early discovery is associated with a 20 percent drop in breast cancer mortality, says Dr Georgette Chan.

That said, routine breast screening is a must – whether breast cancer runs in your family or not – and there are different types of diagnostic options available.

Mammography is the most widely used form of breast cancer screening worldwide, with other methods like ultrasound and magnetic resonance imaging (MRI) typically used for further evaluation, or in conjunction with mammography – particularly for those women at high risk, explains Dr Chan.

In her opinion, the most effective tool for detecting breast cancer is a mammogram – a special type of x-ray that reveals any changes and abnormalities in the breast tissue. It has an accuracy rate as high as 90 to 95 percent, and has proven effective in detecting cancers early, even before any symptoms present, she says.

Three-dimensional development

With recent developments in the field of mammography, Dr Chan says the breast screening process is now more effective than it’s ever been.

One such advancement is 3D mammography (tomosynthesis), which is an extension of a digital mammogram. It’s a screening method that’s been around since 2011, but was only introduced to Singapore in the last couple of years. Though 3D mammography is not available at every centre on the island, Dr Chan’s practice does utilise it alongside 2D mammography, breast ultrasounds and MRI scans.

As with 2D mammograms, she recommends yearly screenings from the age of 40 – or earlier if there’s a family history of breast cancer – and once every two years from the age of 50.

Here, Dr Chan answers a few extra queries about 3D mammography.

How does a 3D mammogram work?

The breast is compressed like in a standard 2D mammogram, and the machine takes multiple low-dose x-ray images as the arm of the mammogram machine moves over the breast. Then, the images are combined to give a three-dimensional picture of the breast, in addition to the standard 2D views.

What are the benefits?

3D mammography has better resolution, a higher accuracy of breast cancer detection and lower false positive rates.

Some breast tumours may be difficult to detect on standard digital 2D mammograms, as the tumours could be obscured by dense breasts or overlapping tissue. Dense breasts are very frequently encountered in our local population and in ladies who are slim.

Some “shadows”, which are seen in 2D mammograms, may just need a clearer view. A 3D mammogram can help provide a clearer view, and help evade any unnecessary biopsies.

This is a particularly beneficial screening tool for patients who have a high risk of developing breast cancer – including those with a strong family history, known genetic mutation or previous breast biopsy with atypical findings. It’s also a good option if your previous mammograms had issues and needed additional views.

Are there any disadvantages?

The tissue compression time may take a few seconds longer, so that might be more uncomfortable. Additionally, the level of radiation is slightly higher than the standard 2D mammogram alone. However, if done at the recommended yearly interval, the amount of radiation accumulated is not high – and this method may see problem areas more clearly.

Dr Georgette Chan

#11-09 Mount Elizabeth Medical Centre, 3 Mount Elizabeth

6836 5167 | georgettechan.com.sg