Mammography is still the gold standard for breast cancer screening and detection. There is some controversy as to when women should start having mammograms and how often, but the American College of Radiology, the National Comprehensive Cancer Network, the Society of Breast Imaging and the American College of Surgeons all agree that screening mammography should begin at age 40 and should continue yearly while a woman is in good health.
A mammogram can be ordered as either a screening mammogram or a diagnostic mammogram. A screening mammogram is appropriate for women without a breast problem. A diagnostic mammogram is appropriate for women with a breast problem such as a lump, pain, discharge, history of breast cancer, or following an abnormal screening mammogram.
While screening mammograms are interpreted by the radiologist in a single session the day following the exam in a quiet environment with minimal interruptions, a diagnostic mammogram is reviewed right away and may include extra mammogram images and in some cases a breast ultrasound.
Following a screening mammogram, about 7 percent of women may be recalled for additional images or an ultrasound to complete the evaluation of an abnormality on the screening images. Most of the time the additional imaging results in a normal or benign finding.
Which type of mammogram is right for me?
Beebe Healthcare offers two options for screening mammography. Digital breast tomosynthesis, also known as 3D mammography, is offered in Rehoboth Beach, Millville, and Georgetown. Traditional mammography or 2D digital mammography is offered at all of Beebe's locations.
Studies have shown that the cancer detection rate is higher for 3D mammography, and the recall rate following a 3D screening mammogram is lower. While every woman can benefit from 3D mammography, the benefits are greatest for women with dense breasts, since having dense breasts can increase the risk of breast cancer and can make breast cancer harder to see on a mammogram. Ultrasound can be used to supplement mammography for women with dense breasts.
Why did my doctor order an ultrasound after my mammogram?
Breast ultrasound is often the next step when there is an abnormality on a mammogram that needs to be evaluated further, or if there is a physical finding such as a mass that is not seen on the mammogram. Ultrasound can also be used in women with dense breasts as a supplement to screening mammography.
Studies have shown that ultrasound can help ﬁnd breast cancers that are not seen on a mammogram. About three to four additional cancers per 1,000 women can be discovered. However, ultrasound also shows some ﬁndings that are not cancer, which can result in added testing and unnecessary biopsies. Also, the cost of ultrasound may not be covered by insurance.
Ultrasound does not replace screening mammography, and the decision to supplement mammography with ultrasound should take the above information into account, along with other factors such as a woman's overall risk of breast cancer.
What is the role of MRI in breast imaging?
MRI is another modality used for imaging the breast in certain circumstances. Breast MRI requires specialized equipment that allows the breasts to be adequately imaged without compression; it is available at the Medical Center in Lewes.
Some women may qualify for a screening breast MRI if they have a high risk of breast cancer (20 percent or greater lifetime risk). A breast MRI may also be ordered to determine the extent of cancer after a new breast cancer diagnosis, to further evaluation of abnormalities that are hard to assess with mammography and ultrasound alone, or to evaluate breast implants for rupture.
Why did I need a biopsy?
Some breast imaging findings may require a biopsy to determine if there is cancer. If the abnormality is visible with ultrasound, the biopsy can be performed using ultrasound guidance. If an abnormality is seen on a mammogram and isn't seen on an ultrasound, such as microcalcifications, a stereotactic biopsy can be performed. This is another type of minimally invasive breast biopsy and is offered at the Bookhammer Outpatient Center on Route 24 near Rehoboth Beach.
While stereotactic biopsy has been available at Beebe Healthcare for many years, we have recently upgraded our equipment to the Hologic Affirm 3D breast biopsy guidance system. This means that the most challenging lesions that are only seen on 3D images can be more precisely localized and successfully biopsied. The unit has a large field of view and allows for advanced patient positioning, resulting in more accurate targeting.
What can I expect?
Both ultrasound and stereotactic biopsy are minimally invasive. They are performed under local anesthesia through a small nick in the skin which minimizes scarring. This is important because more than half of all breast biopsies are benign, and therefore minimal scarring is desirable.
In a small number of cases, a breast abnormality that is recommended for biopsy is not visible by mammography or ultrasound but only by MRI. In these cases, a second-look ultrasound can often find the lesion, but if not, MRI-guided biopsy is a third minimally invasive biopsy option. The MRI scanner at the Medical Center in Lewes is capable of both breast MRI and MRI-guided biopsy. We currently offer breast MRI imaging and plan to offer MRI-guided breast biopsy in the future.
Dr. Ellen Bahtiarian is board certified in Radiology and Nuclear Medicine. She is a member of Southern Delaware Imaging Associates, a group of radiologists who provide imaging interpretations for all of the Beebe Healthcare Imaging locations 24 hours a day, 365 days a year. Find out more about Imaging at Beebe Healthcare at https://www.beebehealthcare.org/patient-care-services/beebe-imaging.