Importance of Breast Screening (3D Mammogram)

Why do women need to undergo breast screening?

Breast screening is physical examination and imaging of breasts for all women regardless of whether they have breast lumps or pain. The main reason for breast screening is to detect breast cancer early. It is recommended that all women aged 50 and above to undergo breast screening. Those who have risk factors for breast cancer such as having BRCA genes or strong family history of breast cancer should undergo breast screening earlier than 50 years old.

How common is breast cancer?

Breast cancer is one of 3 commonest cancer among Malaysians. It is also the number one cause of cancer deaths among women in Malaysia and many countries in the world. According to the Malaysian National Cancer Registry 2007 – 2011, age-standardized rate (ASR) for breast cancer was 31.1 in 100,000 population. Among Malaysian women, the lifetime risk of getting breast cancer is 1 in 20.

The figures still relatively low compared to the United States of America and the United Kingdom. According to International Registry for Research in Cancer (GLOBOCAN) 2012, in the United States the ASR for breast cancer was about 80 in 100,000 population and the lifetime risk of getting breast cancer was 1 in 4.

Despite the lower incidence of breast cancer in Malaysia than countries like the USA, death rates due to breast cancer are much higher in Malaysia. GLOBOCAN 2012 reported death rates due to breast cancer in Malaysia were more than 18.1 per 100,000 in comparison to the USA which has only about 8 per 100,000. One of the known causes of this fact is women in Malaysia with breast cancer tend to seek treatment late.

Why breast screening is important?

The main aim of breast screening is to detect breast cancer early. Early detection of breast cancer not only improves one’s chance of survival, it also improves the likelihood of avoiding mastectomy. Mastectomy is a surgical procedure to remove the whole breast and the nipple.

Who is at risk of getting breast cancer?

Being female by itself is a risk for getting breast cancer. This risk increases by the age of 40 years old for the pre-menopausal group and 50 years old for the post-menopausal group. Other identified risks for breast cancer are; those who had breast cancer before or breast cancer in situ (e.g. lobular carcinoma in situ and ductal carcinoma in situ), those who had breast lump that can predispose to cancer such as atypical ductal hyperplasia, those who has a genetic tendency for breast cancer such as BRCA 1 and BRCA 2. Those with a strong family history of breast cancer are also at risk.

Modifiable and less strong risk factors are such as continuous (more than 2 years) intake of oral contraceptive pills, smoking, alcohol intake, obesity, sedentary and inactive lifestyle and previous history of repeated radiation exposure to the chest.

What is the best screening method for breast cancer?

Breast examination alone either performed by yourself or by medical personnel is not adequate and ineffective in reducing breast cancer mortality. Although there is no evidence on the effectiveness of breast self – examination, this practice has been seen to empower women and encourage them to take responsibility for their own health. Breast self – examination is still recommended for raising awareness among women at risk rather as a sole screening method. Detecting breast cancer still requires a combination of clinical examination and imaging tools.

There are many imaging methods to detect and assess for breast cancer such as ultrasonography, mammogram, CT and MRI of the breast. Many studies and trials evaluating the role of various imaging modalities used in the screening and diagnosis of breast cancer revealed that mammogram is the only imaging technique that has a significant impact on screening of asymptomatic women or breast cancer. Breast ultrasound and breast MRI are frequently used as adjuncts to mammogram in treatment planning and staging and not for screening.

Therefore, mammogram remained the best screening method for breast cancer. The Malaysian Clinical Practice Guidelines on the management of breast cancer 2010 recommended that mammogram may be performed once every 2 years in all women from 50 – 74 years of age.

What is 3D mammogram?

A conventional mammogram uses a small x-ray machine that delivers very low dose radiation to the breasts that need to be compressed between 2 plates in the machine. Compression of the breast is necessary to spread out the breast tissue and to reduce motion, which may blur the mammogram image. X – rays of the breast are taken in 2 views; the top to bottom craniocaudal view and the side to side MLO view.

3D mammogram or breast tomosynthesis is a relatively new breast imaging procedure that is very similar to the conventional mammogram. The machine is similar to conventional mammogram, it still requires the breast to be compressed between 2 plates of the machine, and it also uses X – rays to produce images of breast tissue in order to detect lumps, tumours or other breast abnormalities.

Unlike conventional mammogram that can only produce 2 views or images of the breast, 3D mammogram produces many X-ray images of the breasts from multiple angles to create a digital 3-dimensional reconstruction of internal breast tissue.

Why 3D mammogram is better than conventional mammogram?

3D mammogram captures multiple slices of the breast, all at different angles. All the images are brought together and the radiologist; the doctor who interprets the images able to review the reconstruction, 1 slide at a time. This makes it easier for the doctor to look for abnormalities in the breast. The radiologist can view the breast in 1-millimetre slices’ rather than just the full thickness from vertical top to bottom and from the side.

Many research reported the 3D mammogram has a higher detection rate of breast cancer; it can find 41% more lesions of breast cancer versus the conventional 2D mammogram. It is also more accurate and has higher clinical efficiency; it reduces recalls due to false positive by up to 40%.

The mechanics and design of the 3D mammogram machine also provide better comfort to patients. Because the breast no longer needed to be even out and fully compressed, positioning of the patient and imaging of the breast is no longer painful or uncomfortable.