Demystifying Mammograms

Put common worries about this breast cancer screening method to rest.

Portrait of Tammy Strobel

Put common worries about this breast cancer screening method to rest.

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In Singapore, breast cancer is the common cancer among women, and it occurs when certain cells in the breast become abnormal and multiply uncontrollably to form a tumour. While this sounds scary, early detection usually results in a high survival rate (80 per cent at 10 years after discovery). This means – you guessed it! – it’s best to go for screening. In Singapore, this is recommended every one to two years for women between the ages of 40 and 49.

The idea of having your lady lumps squished between two metal plates is definitely not fun, but a mammogram is the only effective and proven method of breast cancer screening.

In general, it is able to detect about 85 per cent of all breast cancers, says Dr Chan Ching Wan, head and senior consultant at the Division of General Surgery (Breast Surgery), National University Hospital.

Dr Chan dispels your fears as she sheds light on common misconceptions about mammography.

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MYTH The size of your breasts affects how accurate the mammogram results will be.

TRUTH Unless you are completely fl at, the size of your boobs – small or big – has no effect on the accuracy of results, says Dr Chan. What really aff ects readings is actually breast density. “This is the main reason why mammograms are less effective among younger women. As we get older, breast tissue is gradually replaced by fat. In a nutshell, more fat means lower breast density, and this makes it easier for mammograms to identify new changes.”

MYTH The radiation is harmful.

TRUTH This is one of the most common fears surrounding mammography. According to Dr Chan, “The total lifetime exposure is very low, and does not cause any harm. In fact, the radiation dose of a mammogram is very much lower than that of a computed tomography (CT) scan.”

MYTH An ultrasound screening is just as effective as a mammogram.

TRUTH While ultrasound scans are very sensitive and good at finding nodules and cysts, they cannot tell if a nodule is cancerous. Dr Chan also points out that the quality of a scan relies very much on the technician doing it. Ultrasounds are complementary to mammograms and are used when there’s a need to see more detail in an area highlighted by a mammogram or physical examination.

MYTH There is no way to reduce discomfort during mammograms.

TRUTH Timing matters. Dr Chan recommends scheduling a mammogram after your period instead of before it as that is when your boobs are the least sensitive.

MYTH You don’t need to do mammograms if you do frequent breast self-examinations.

TRUTH Self-exams can help to detect lumps, but these lumps have to be big enough to be felt by your fingers. Moreover, if you have bigger boobs and the lump is in the centre of the breast tissue, you won’t be able to feel it until it has grown quite big. Mammograms can identify abnormalities and spot lumps that are as small as 5mm.

MYTH An abnormal mammogram reading means that you have breast cancer.

TRUTH Thankfully, this is just a myth. “Based on data from screening programmes, about 10 in 100 women will be called up for an abnormality seen in a mammogram. Of these 10 women, three to four may have cancer.”

MYTH A doctor will be able to tell if you have breast cancer simply by looking at a mammogram reading.

TRUTH “Mammograms – and all imaging technologies at present – can only give a predictive score of the likelihood of cancer,” says Dr Chan. “The only method of confirming that a lump is cancerous is by having a biopsy done, where a small tissue sample is taken and analysed under the microscope for diagnosis.”


Surgery, chemotherapy and radiation therapy are the main forms of treatment for breast cancer. When the disease is discovered at an early stage, surgery is usually the treatment of choice as it is the only way to totally rid the body of cancer. Thanks to medical and technological advancements, total mastectomies are no longer necessary for most patients. However, in the case of lumpectomies, where only the lump and some surrounding tissue are removed, patients will have to undergo radiation therapy to prevent the cancer from returning. Speak with your doctor to determine the best treatment option for you.