Guidelines for Breast Cancer Screening

It is recommended that all women from 50-69 have mammogram every two years. A breast examination and ultrasound are not routinely recommended. In addition, women from 40-49 should know their risks and benefits and decide if they want to do a breast mammogram yearly. Normal women under the age of 40 do not need breast imaging.

Breast cancer is the most common cancer in women and affects up to 6 percent of all women during their lifetime. The incidence of breast cancer in women is going up at about 4 percent per year. In western countries, mammogram is recommended for women aged 70-75; however, in Singapore, there are fewer women in this age group who develop breast cancer so that doing a mammogram depends on the patient and the doctor at every two year intervals. Tests like a CT of the breast, PET scan of the breast, thermal imaging and optical imaging, among other nonconventional methods should not be used to examine the breasts for cancer.

Risk factors for breast cancer need to be considered. This includes having an early menarche, having a late age at menopause, having the first live birth at a late age, having certain premalignant conditions of the breast, being on hormone replacement therapy and having a family history of a first degree relative with breast cancer.

For example, women with lobular carcinoma in situ have a 5-10 fold increase in breast cancer and women with a first degree relative with breast cancer have a 10-15 fold increase in the risk of breast cancer. Women with family histories may want to go ahead and have genetic testing for breast cancer genetic markers. Such women usually have breast cancer before the age of 40.

Mammography continues to be the best screening tool for breast cancer. It involves squeezing the breast between two x-ray plates and taking an x-ray picture. It can detect small tumors at earlier breast cancer stages so that breast cancer survival is better. The goal is to find more pre-invasive tumors before they get too lethal. It decreases the mortality rate because tumors are found earlier when the mortality rate is lower.

A breast ultrasound is used to detect the difference between solid lumps and fluid-filled cysts. It is sometimes used when the mammogram is indeterminate as to the cause of the lump seen. A breast ultrasound can be done with a needle that is used to aspirate out any cells and fluid that might be in the lump. Breast ultrasounds are really not good tests, however, for primary screening.

A breast MRI is highly sensitive for picking up breast tumors but is not very specific. A follow up ultrasound would have to be done to make sure the lump was not a cyst. It causes a greater number of biopsies to be done than a mammogram does.