T, a 46-year-old housewife looked apprehensive and was fidgety while waiting for the result of her mammogram. She felt a lump, the size of a fish ball, in her right breast 3 weeks ago.
“I felt the lump while bathing. It was firm but not painful. I did not have any nipple discharge. My husband and daughter encouraged me to go for a mammogram. I was resistant to the idea initially and was reluctant to do so as I did not have a family history of breast cancer and was told the procedure was very uncomfortable and painful,” she said.
Her mammogram was indeed abnormal and was reported as BI-RADS 5 which was highly suggestive of cancer. She was referred to a breast surgeon who did a biopsy on the lump and confirmed that it was cancerous.
What is a mammogram?
A mammogram is a specialized low-dose X rays to image the breasts. It is used to detect early breast cancer before the growth can be felt by a physical examination. Early detection and treatment greatly enhances the chances of survival. In Singapore, as many as 2000 women are diagnosed with breast cancer every year. This makes it the most common female cancer.
How is a mammogram done?
Using a specialized X-ray machine, the technician places each breast on a flat X-ray plate. A compressor is gradually applied on the breast for a few seconds to spread out the breast tissue evenly for the X-rays to penetrate. The images are then captured and read by the radiologist.
The mammogram is usually uncomfortable because of the compression. But this step is necessary as the pressure keeps the breast from moving which may cause blurring of the images and it also minimizes the dose of radiation required. The discomfort or pain, however, is usually short-lived.
When should mammography be done?
There is no ideal age to start screening for breast cancer. Women with an average risk may begin mammograms at age 40 and have them every one to two years.
Professional organizations also differ on their recommendations. The American Cancer Society advises women with an average risk to begin screening mammograms yearly at age 45 until age 54, and then continue every two years. The U.S. Preventive Services Task Force recommends women start screening every two years starting at age 50 until age 74.
However, these groups agree that women can choose to be screened starting at age 40.
In Singapore, BreastScreen Singapore (BSS) , the national breast cancer screening programme recommends annual screening from age 40 to age 49 and once in two years from age 50 onwards.
Women with a high risk of breast cancer such as a family history of breast cancer or a history of precancerous breast lesions may benefit by beginning screening mammograms before age 40. Magnetic resonance imaging (MRI) in combination with mammograms may also be done to achieve optimal result.
What are the risks and limitations of mammograms?
Risks
Many women are concerned about the radiation exposure from mammograms. The risk is low and is equivalent to about 6 months of background radiation exposure from daily living. For most women, the benefits of regular mammograms outweigh the risks posed by this amount of radiation.
Limitations
While mammography is an excellent screening tool for breast cancer, mammograms do not detect all breast cancers. The accuracy of the procedure depends on the technique used, age of the patient and breast density. It may give false-negative or false-positive results.
Mammograms in younger women can be difficult to interpret. The breasts of younger women contain more glands and fibrous tissue than do those of older women, resulting in dense breast tissue that can obscure signs of cancer. With age, the breast tissue has more fatty tissue and fewer glands, making it easier to interpret and detect changes on mammograms.
How is the mammogram reported?
The mammogram is usually reported according to the diagnostic system developed by American College of Radiology called BI-RADS, or the Breast Imaging Reporting and Database System. In this system, there are seven categories, ranging from zero to six. Each category describes whether additional images are necessary, and whether an area is more likely to have a benign (noncancerous) or cancerous lump.
T had her right breast removed by surgery followed by chemotherapy. She remained well for the past 5 years. On her recent visit for her gynecological check-up, she was in good spirits. “ Doc,” she said, “luckily the mammogram picked up my cancer early. My surgeon told me that I should have excellent prognosis.”