Current guidelines from the American Cancer Society recommend that women start annual screening mammography at age 40. Screening mammography is performed to find cancers early before they can be felt on physical examination. A mammogram is a specialized low dose x-ray of the breast. It uses very low levels of radiation. Mammography is an excellent tool for early detection of breast cancer but it is not perfect. Women with breast implants should continue to have mammograms. It is important that you inform the mammography clinic that you have implants when you schedule your mammogram. There are some patients that may start screening earlier than age 40. These include patients who have had upper body radiation for lymphoma as a child, first degree relatives (sister, daughter) of women diagnosed with PREMENOPAUSAL breast cancer and some women who have a very rare gene mutation.
What should I expect at my appointment?
When possible, schedule your mammogram at the time of your menstrual cycle when your breasts are less tender, the best time is one week following your period. It is best to wear a 2-piece outfit, as you will be removing your top clothing. Do not wear perfume, deodorant, powder or lotion under your arms on the day of your mammogram as they could cause an artifact on the x-ray. During your mammogram your breast will be compressed between two plates and an x-ray will be taken. At least two views are performed of each breast. The routine views are a top to bottom view and a side view. The compression may be uncomfortable but it is very important because it spreads the tissue more evenly and improves the quality of the image. Compression allows the use of a lower x-ray dose since a thinner amount of tissue is being imaged. Compression also holds the breast still to eliminate blurring and reduces x-ray scatter, which also leads to poor image quality.
Who interprets the results and who performs the mammogram?
A radiologist, who is a physician experienced in mammography and other imaging examinations, will analyze the images. A radiologist must have passed a licensing examination and completed at least four years of residency and are usually board certified by the American Board of Radiology. The report will be dictated by the radiologist and then sent to your referring physician. You will also be notified of the results by the mammography facility. Interpretations of mammograms can be difficult because a normal breast can have a different appearance in each woman. Not all breast cancers can be seen on mammographic images
A radiologic technologist will perform the examination. Technologists undergo one to four years of formal training leading to a certificate, associate's degree, or bachelor's degree. With additional training, a technologist can specialize and work almost exclusively with specialized radiographic equipment.
Patients who have specific symptoms related to their breasts are scheduled for diagnostic mammograms. These exams are directed at addressing a specific question. Patients who have new breast lumps, new specific kinds of nipple discharge, focal persistent areas of breast pain, prior breast cancer, breast implants, possible abnormalities identified on a screening mammogram, or short follow-up (i.e. for example, 6 months) of an abnormality are usually scheduled for diagnostic mammograms. The exact protocol may vary at each institution. Diagnostic mammograms are dedicated special x-ray views such as magnification or spot compression views that help characterize or define a possible abnormality. For more information see above.
Ultrasound sends sound waves into the breast and a computer converts these signals into an image of the inside of your breast. Ultrasound is a useful tool in evaluation of the breast. It is usually the first study done in a woman with a mass who is less than 30 years old. It is also very useful to help characterize possible abnormalities on your mammogram or possible lumps. Ultrasound can be used to determine if a mass is fluid filled (a cyst) or solid. It can also be used to better characterize solid masses.
A ductogram may be performed to evaluate certain kinds of nipple discharge. A small amount of dye in injected into the duct (through the nipple) and special mammogram pictures are performed.
Magnetic Resonance Imaging or MRI is performed to evaluate for rupture of breast implants. MRI can also be performed in some patients who have breast cancer to evaluate the extent of tumor.
Image Guided Biopsy
When a biopsy is performed a small amount of tissue is removed from a mass or area of calcifications and examined under the microscope by a pathologist. There are many ways to biopsy the breast. If the surgeon can't feel the area of concern, image guided biopsy or needle localization can be performed. A radiologist will use either ultrasound or special x-ray views (stereotactic views) or ultrasound to guide a needle into the area to be biopsied. Either a core biopsy or a vacuum assisted (Mammatome) biopsy can be performed. When the calcifications are too faint to be seen with the stereotactic views, the area to be biopsied is in an inaccessible location, or if patient or surgeon request, a needle guided excisional biopsy is performed. MRI guided image bio often may also be performed.
Stereotactic biopsy: The patient lies face down on a table with a hole in it. The patient's breast is placed through the hole and is compressed between two x-ray plates beneath the table. Special pictures are taken and a computer is used to accurately locate the abnormality. After injecting local anesthetic, the radiologist then uses the information generated by the computer and a special guide to place the needle into the abnormality. The needle used in this procedure at NMCP is a Mammatome needle. It uses vacuum and a small rotating cutter to remove samples from the area of concern. Many samples are taken from the area. This device is able to remove larger samples. There is a small incision in the skin but it is so small that stitches are not needed. Patients can usually resume her normal routine following the procedure.
Ultrasound guided biopsy: Ultrasound is used to biopsy masses, not microcalcifications, as calcifications are very difficult to see with ultrasound. The patient lies on her back on the table and ultrasound is used to find the abnormality. The radiologist uses ultrasound to guide a needle into the mass. Multiple (usually greater than 5) biopsies are performed. The radiologist can either use a hand held Mammatome or a core biopsy device to take samples. The mammatome uses vacuum and a rotating cutter to take samples. Core biopsy devices rapidly propel a needle with a special notch and cutter through the mass and remove the sample. There is a small incision in the skin but it is so small that stitches are not needed.
Needle guided excisional biopsy: Special mammography views are used to localize the area of concern. The radiologist uses these views to place a guiding needle and wire into the abnormal area to mark the area for the surgeon. The radiologist can also use ultrasound to guide placement of this needle/wire. During surgery the surgeon uses the needle/wire as a guide to find the mass.