Resources

Q

What is a mammogram?

A

A mammogram is a radiographic image that gives a picture of the internal structure of the breast. There are two types of mammography: screening and diagnostic.

A screening mammogram is performed on women who have no evidence of breast disease. Using a mammography machine, a radiologic technologist obtains two views of each breast. Screening mammography is the best way to detect breast cancer early. A screening mammogram is similar to other screening exams such as a PAP smear, PSA for prostate cancer, fecal occult blood to detect colon cancer and a glucose test to detect diabetes.

Yearly screening mammography should be a routine procedure for all women ages 40 and older. Women with a strong family history (mother, sister or daughter) of premenopausal breast cancer may wish to begin screening earlier.

Diagnostic mammography is performed when a possible abnormality, such as a lump, has been found on a screening mammogram or upon clinical examination of the breast. It includes special views in order to better evaluate the abnormality. A diagnostic mammogram is read by the radiologist at the time of the exam.

Q

Who is the radiologist?

A

Radiologists are physicians who specialize in all aspects of imaging the body. This includes exams used to diagnose abnormalities and in performing biopsies of tissues that require imaging guidance (example: biopsies of breast lesions that cannot be felt). Radiologists understand radiation safety issues and the methods by which images are acquired, which makes them uniquely qualified to interpret imaging studies and to perform image guided biopsies.

Radiologists have 4-6 years of specialized training after earning a medical degree. Those who read mammograms have additional training solely devoted to breast imaging. To maintain certification to read mammograms, the radiologist must read many mammograms a year, maintain continuing education credits pertinent to mammography and are subjected to medical audits. Statistical results are compared to local and national results.

Q

What does it mean to have an "abnormal" mammogram?

A

A finding on your screening mammogram requires further evaluation to determine if it is suspicious. This evaluation usually involves specialized mammographic views. It may require physical exam, ultrasound or an MRI exam. Most of these “abnormal” findings can be resolved as benign (not cancer) on subsequent imaging. If they cannot be resolved as benign, then a follow-up study or biopsy may be recommended.

Q

Why might my doctor recommend a 6 month follow-up exam for an abnormal finding?

A

A six-month follow-up may help to avoid unnecessary biopsies.

Almost all women have lumps, calcifications or abnormal densities on their mammograms. The radiologist assesses the risk that these may be cancer based on their appearance, the patient’s age, clinical history, use of estrogen, family history, and whether or not the abnormality has changed compared with prior mammograms. This is why it is so important to have your previous mammograms available.

After thorough assessment, if the radiologist finds no suspicious features, he/she may recommend a follow-up study in 6 and 12 months to make sure the area doesn’t change. This is a well-researched, widely practiced, and acceptable method to deal with “probably benign” abnormalities.

Q

What is the chance that an abnormality followed at 6 and 12 months is really a cancer?

A

This does happen, but it is uncommon. These “probably benign” findings have been well-researched. For example, in a research study involving thousands of women being followed for probably benign masses, only 1.7% were ultimately found to be cancer. These were diagnosed because they grew on the follow-up studies and were eventually biopsied. One-third of these had grown at the six month study, 1/3 did not show growth until the 12 month study, and 1/3 did not show growth until the 24 month study. Because “benign” appearing cancers are usually the slow-growing variety, these patients still presented with early stage cancers (same prognosis as if biopsied initially).

The six-month follow-up practice is used to prevent many unnecessary biopsies.