High-Resolution Breast PET Imaging Combined with MRI Improves Breast Cancer Detection

Recent findings demonstrate that positron emission mammography (PEM) improves breast cancer detection. PEM significantly improves ability to differentiate between benign and cancerous lesions. Moreover, the combination of PEM and breast magnetic resonance imaging (MRI) dramatically increased number of suspicious lesions detected.

A U.S. National Institutes of Health (NIH; Bethesda, MD, USA)-sponsored, multiyear study of hundreds of women diagnosed with breast cancer revealed that PEM scanners considerably outperform MRI when differentiating between benign and cancerous lesions. The prospective study also found that the combination of PEM and breast MRI significantly increases a physician's ability to detect potentially cancerous lesions over MRI alone, presenting a powerful combination for improving care. These findings mean that women and their physicians now have a better tool to help cure cancer.

PEM scanners are high-resolution breast positron emission tomography (PET) systems that can show the location as well as the metabolic phase of a lesion. This information is vital in determining whether a lesion is malignant and influences the course of treatment. Other imaging systems, such as mammography and ultrasound, only show the location, not the metabolic phase. PEM scanners, which are approximately the size of an ultrasound system, are made in San Diego, CA, USA, by Naviscan, Inc. and have been commercially available since 2007.

The NIH study examined 388 women with newly diagnosed breast tumors, and unlike earlier studies on primary lesions, focused on additional or secondary tumors. Determining the presence of additional tumors is essential to understanding if a lumpectomy or mastectomy is the appropriate surgery. Researchers found that PEM scans accurately distinguished 151 of 189 benign additional lesions, an 80% success rate in specificity. When the same lesions were subject to MRI scans, the specificity slipped to just 66%.

The study also found that the most effective way to identify lesions was to combine the two technologies. PEM and MRI scanning together saw an additional 31 (out of 116 total) lesions producing a 20% absolute increase in sensitivity when compared to using MRI alone.

"We looked very carefully for additional cancers and were surprised that barely half of these were shown on MRI,” said Wendie Berg, M.D., Ph.D. principal investigator for the trial. "Clearly there is need for better surgical planning information. PEM significantly improved detection of additional disease over MRI alone.”

The results validate PEM as an integral imaging tool in the surgical management of breast cancer, and as an alternative for the large number of patients who cannot tolerate breast MRI exams due to claustrophobia, patient comfort, pacemaker, metal implants, or other factors. "This new technology, available to patients at more than 35 sites throughout the U.S. and internationally, represents a significant advance in the detection and treatment of breast cancer. Comprehensive breast cancer centers and existing imaging centers with MRI capability will benefit from the additional sensitivity and specificity provided by PEM,” said Paul J. Mirabella, Chairman and CEO, Naviscan.

This multisite study examined women with newly diagnosed breast cancer. Patients were accrued from six leading clinical centers across the United States.

Naviscan develops and markets compact, high-resolution PET scanners intended to provide organ-specific molecular imaging and guide radiologic and surgical procedures. The Naviscan PET scanner is currently installed and available in breast and imaging centers throughout the United States and other parts of the world. The company is the first company to obtain U.S. Food and Drugs Demonstration (FDA) clearance for a high-resolution PET scanner designed to image small body parts and for breast biopsy image guidance.

Related Links:
National Institutes of Health