ST LOUIS: Ultrasound has long been a cornerstone in breast cancer diagnosis, effectively identifying fluid-filled cysts that are typically non-cancerous. However, its limitation lies in distinguishing between benign and malignant solid masses, often forcing doctors to rely on invasive biopsies for definitive answers.
The Problem of Unnecessary Biopsies
In the United States alone, over 1 million breast biopsies are performed annually, with a staggering 80% returning benign results. These unnecessary procedures carry significant drawbacks, including heightened patient anxiety, potential complications from the invasive technique, and substantial medical costs. Despite advancements in breast imaging technology, biopsy remains the only conclusive method to confirm cancer presence in suspicious lumps.
Engineering a Better Solution
My work as an engineer focuses on enhancing imaging technology for cancer detection and diagnosis. Breast cancer tumors exhibit distinct biological characteristics: they generate new blood vessels and consume more oxygen than surrounding tissue. This makes blood vessel density and oxygen levels promising biomarkers for improved diagnosis.
Diffuse optical tomography (DOT) represents a breakthrough in this area. This imaging technology utilizes near-infrared light to measure total blood hemoglobin concentration and oxygen saturation levels within breast tissue—key indicators of tumor activity. Crucially, DOT requires no contrast dye injections, making it safer and more accessible for patients.
Combining Structure and Function
My research team discovered that integrating ultrasound with DOT creates a powerful diagnostic tool. While ultrasound provides detailed structural information about breast lumps, DOT reveals their functional characteristics. Together, these complementary datasets significantly enhance diagnostic accuracy.
Clinical Study Results
In our comprehensive study, we imaged 226 patients scheduled for routine breast biopsy using our novel hand-held device that merges ultrasound with DOT technology. All participants had either confirmed breast cancer or benign lumps, with biopsy results serving as the definitive diagnosis.
Radiologists first evaluated each case using standard imaging methods like ultrasound and mammography. They then reviewed additional data from DOT images, with both radiologists and engineers blinded to biopsy results during diagnosis determination.
The findings revealed striking biological differences: cancerous lesions displayed significantly higher hemoglobin concentrations and lower oxygen levels compared to noncancerous tissue. More aggressive tumors showed even more pronounced hemoglobin elevation and oxygen depletion.
Most importantly, when radiologists incorporated DOT measurements into their assessments, biopsies of benign lumps decreased by approximately 25%. The technology maintained a false-negative rate of just 1.8%, well within medical guidelines that recommend monitoring rather than immediate biopsy at such levels.
The Future of Breast Cancer Diagnosis
Breast cancer remains the most commonly diagnosed cancer in women globally, with approximately 2.3 million new cases and 670,000 deaths reported in 2022. Projections suggest these numbers could rise to around 1.1 million breast cancer-related deaths annually by 2050 if current trends continue.
More accurate, noninvasive diagnostic tools like the ultrasound-DOT combination offer multiple benefits beyond reducing unnecessary biopsies. They enable more precise diagnoses and streamline the diagnostic process. Researchers are also exploring DOT integration with other imaging modalities, including X-ray mammography, 3D mammography, and MRI.
However, DOT systems paired with mammography and MRI present greater challenges for routine clinical use compared to ultrasound combinations. My team continues to refine our technology, incorporating artificial intelligence tools to enhance imaging data processing and interpretation.
Broader Implications
Minimizing avoidable medical procedures preserves patient quality of life while reducing healthcare system burdens. By decreasing unnecessary biopsies, we can alleviate patient anxiety, lower complication risks, and contain medical costs. I believe these technological improvements will collectively create meaningful, far-reaching impacts on patient care and healthcare delivery systems worldwide.
