FDA approves first breast ultrasound imaging system for dense breast tissue

Device designed to help health care providers detect smaller tumors

October 18, 2012
U.S. Food and Drug Administration (FDA)

The U.S. Food and Drug Administration today approved the first ultrasound device for use in combination with a standard mammography in women with dense breast tissue who have a negative mammogram and no symptoms of breast cancer.

Breast cancer is the second leading cause of cancer-related death among women. This year an estimated 226,870 women will be diagnosed with breast cancer, and 39,510 will die from the disease.

The National Cancer Institute estimates that about 40% of women undergoing screening mammography have dense breasts. These women have an increased risk of breast cancer, with detection usually at a more advanced and difficult to treat stage.

Dense breasts have a high amount of connective and glandular tissue (fibroglandular tissue) compared with less-dense breasts, which have a high amount of fatty tissue. A physician determines if a woman has dense breast tissue with a mammography exam.

Mammography is a low-dose X-ray imaging method of the breast. However, mammograms of dense breasts can be difficult to interpret. Fibroglandular breast tissue and tumors both appear as solid white areas on mammograms. As a result, dense breast tissue may obscure smaller tumors, potentially delaying detection of breast cancer.

Ultrasound imaging has been shown to be capable of detecting small masses in dense breasts. During an ultrasound exam, a device called a transducer directs high-frequency sounds waves at the portion of the body being examined. Software analyzes the differences in how the sound waves are reflected off different tissues and back to the transducer to create an image a physician can review for abnormalities.

The specially shaped transducer of the somo-v Automated Breast Ultrasound System (ABUS) can automatically scan the entire breast in about one minute to produce several images for review.

As part of the approval process, the FDA reviewed results from a clinical study in which board-certified radiologists were asked to review mammograms alone or in conjunction with somo-v ABUS images for 200 women with dense breasts and negative mammograms.

Biopsies were performed on masses detected with the somo-v ABUS to determine if they were cancer. The results show a statistically significant increase in breast cancer detection when ABUS images were reviewed in conjunction with mammograms, as compared to mammograms alone.

"A physician may recommend additional screening using ultrasound, for women with dense breast tissue and a negative mammogram," said Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostic Device Evaluation and Safety at FDA's Center for Devices and Radiological Health. "The somo-v ABUS is a safe and effective breast ultrasound tool when such screening is recommended."

The somo-v ABUS is approved for use in women who have not had previous clinical breast intervention, such as a surgery or biopsy, since this might alter the appearance of breast tissue in an ultrasound image.

As part of the approval, FDA has required that the manufacturer provide thorough training for physicians and technologists using the ABUS device, and that the manufacturer provide each facility with a manual clearly defining system tests required for initial, periodic, and yearly quality control measures.