New Imaging Technique May Reduce Unnecessary Breast Biopsies

Researchers have developed a noninvasive imaging method that could help reduce the number of unnecessary breast biopsies, offering women a less invasive and potentially more accurate path to diagnosis. The approach, known as ultrasound-guided diffuse optical tomography (US-DOT), combines near-infrared light and ultrasound to create three-dimensional maps of breast tissue, providing both structural and functional information about lesions.

Unlike traditional imaging modalities that focus solely on physical characteristics, US-DOT gives insight into physiological changes, such as total hemoglobin concentration and blood oxygen saturation. These biomarkers are useful in identifying malignancies, as cancerous tissues often have higher blood supply and altered oxygen levels.

“With diffuse optical tomography, the resolution is lower because light is scattered in the tissue,” said Quing Zhu, PhD, professor of engineering at Washington University in St. Louis and lead author of the study. “Because of the ultrasound localization, we avoid the uncertainty and improve diffuse optical tomography.”

Zhu and her colleagues recently evaluated US-DOT in a double-blind clinical trial involving 226 patients undergoing diagnostic evaluation for suspicious breast lesions. Each participant received a standard ultrasound and mammogram, with radiologists assigning BI-RADS scores both with and without access to US-DOT results. The imaging data included functional maps showing hemoglobin concentration and oxygenation levels in the breast tissue.

Among the women studied, 70 were diagnosed with invasive cancers, seven had ductal carcinoma in situ, and nine had high-risk lesions. The remaining 140 cases were benign. The data showed that malignant lesions were associated with significantly higher hemoglobin concentrations and lower oxygen saturation levels compared to benign ones.

Notably, the researchers found that the inclusion of US-DOT data could have prevented approximately 25% of the participants from undergoing biopsy procedures that ultimately yielded benign results. Zhu emphasized that the radiologists in the trial initially evaluated patients using the standard of care, and only afterward were given the additional US-DOT information to reassess the need for biopsy.

“The radiologists did not know our results, but evaluated each patient based on standard of care to get a risk evaluation and determine whether to do a biopsy,” she said. “Then they used our breast lesion hemoglobin maps and oxygenation saturation levels to decide upgrading or downgrading the lesion regarding a biopsy decision.”

The research team is now focused on refining the system’s imaging capabilities and making the technology more cost-effective for wider use. With further development and regulatory review, US-DOT could eventually serve as a valuable clinical tool to reduce unnecessary biopsies and improve breast cancer diagnostics.