Current Methods for Detecting Breast Cancer

Ultrasound is used to further evaluate abnormalities found in mammography. An ultrasound uses sound waves to create images and recognize irregularities in the breast. It is an effective way to differentiate between cystic and solid masses in the breast and can be a very useful diagnostic tool. In addition, ultrasound is often used to guide biopsy procedures.

Solid masses discovered by ultrasound may be benign or malignant and often this modality helps the physician to determine the need for a biopsy. However, there are cases where mammography and ultrasound together are still unable to provide a clear picture for the physician.

A negative ultrasound in patients with a palpable mass (felt externally by touch) cannot be used to completely rule out cancer, as some tumors may be undetectable to ultrasound.

Magnetic Resonance Imaging (MRI) utilizes a magnetic field to visualize the features of soft tissues with highly detailed resolution, even in cases of dense breasts or implants.

During an MRI, you lie still inside of a narrow tube as the machine creates images of your body. Like an X-ray, the images are taken of anatomical structures and then a contrast media, called Gadolinium, is often injected. This contrast media makes areas of increased blood flow show up as bright spots in the image. Since cancers have increased blood flow, they show up as areas of enhancement. Images of the breast are reconstructed in slices from several different angles.

Unfortunately, not all cancers are visible on MRI and some cancers, such as ductal carcinoma in-situ and lobular carcinoma, are more difficult to detect using MRI. In addition, there are many benign conditions that have increased blood flow and these also enhance under MRI. These enhancements are false-positives and can make treatment planning difficult as well as lead to unnecessary biopsies. One study found that in using MRI in patients with one known cancer, 78 percent of the additional areas detected were benign at biopsy.

A number of nuclear medicine techniques have been proven to assist in diagnosing cancer. These techniques are effective in the early detection of cancer and can be used to help distinguish malignant and benign tumors through the cellular absorption of a tracing agent.

For functional imaging, tests specific to breast imaging such as breast scintigraphy, also known as Breast-Specific Gamma Imaging (BSGI), or molecular breast imaging (MBI) and Positron Emission Mammography (PEM) reveal tumors in dense or surgically altered breasts. While BSGI can be used in patients with difficult to diagnose breast tissue, most insurance companies limit the use of PEM to patients with known cancer diagnosis.

Breast-Specific Gamma Imaging/Molecular Breast Imaging (BSGI/MBI) exceeds its predecessor — scintimammography — in the detection of smaller, earlier stage cancers. BSGI relies on advanced imaging technology and superior positioning to get optimal results.

A high-resolution, small field-of-view gamma camera was developed and then optimized for breast imaging. BSGI also uses a small injection of radioactive material that in breast cancers are revealed as "hot spots" in the image. This is because cancerous cells have a higher rate of metabolic activity than normal cells, and absorb more of the tracing agent at a faster rate than healthy tissue.

By viewing the areas of concentrated radioactive material, radiologists can identify where cells are suspiciously active. These areas indicate the possibility of a cancer or high-risk lesion.

Although BSGI is a very useful imaging modality, like all other tests, it has some limitations. First, this test also experiences false-positive findings. A recent study found that in using BSGI on patients with one known cancer, 7 percent of the additional areas enhancing were benign (compared to MRI where 78 percent of the additional areas were benign). In addition, some cancers are missed by BSGI. One last limitation is that unlike MRI, it cannot see the extension of cancers through the pectoralis muscle, so MRI is a better choice for patients with very large tumors (compared to breast size) and for patients with aggressive cancers near the chest wall.

BSGI: See What Matters^TM… Now

Many women are told to "wait and see" for a six-month follow up after a suspicious mammogram, prolonging the fear and anxiety. Oftentimes, biopsies are performed that are traumatic and can leave scarring — a large percentage of these result in benign findings. BSGI is a valuable "next step" when faced with a questionable mammogram that can help you and your physician obtain accurate answers fast.

The BSGI procedure allows for same-day results and can help evaluate the need for biopsy.

Pairing mammography and BSGI, allows physicians to image the anatomy and physiology of the breast resulting in a powerful advantage for breast cancer detection. (Margaret L. Bertrand M.D., Miami Breast Conference, 2008)