Researchers use photoacoustic tomography, US to detect ovarian tumors
Researchers from Washington University in St. Louis, Missouri, have conducted a pilot study using photoacoustic tomography and ultrasound (US) to assess ovarian tumors, sharing their findings in Radiology.
The team, led by Quing Zhu, PhD, a professor of biomedical engineering at the Washington University School of Engineering & Applied Science, noted that its research could potentially lead to an improved diagnostic imaging technique in patients with ovarian cancer.
“When ovarian cancer is detected at an early, localized stage—stage 1 or 2—the five-year survival rate after surgery and chemotherapy is 70 to 90 percent, compared with 20 percent or less when it is diagnosed at later stages, 3 or 4,” Zhu said in a prepared statement issued by the university. “Clearly, early detection is critical, yet due the lack of effective screening tools only 20-25 percent of ovarian cancers are diagnosed early. If detected in later stages, the survival rate is very low.”
Typically, transvaginal US is utilized to assess and diagnose ovarian tumors; however, this method tends to lack accuracy. Photoacoustic tomography can offer information into the tumor’s angiogenesis and blood oxygen saturation, which are related to the tumor’s growth, metabolism and therapeutic response. This information helps provide a more accurate diagnosis.
The study, which included 16 patients, involved creating a covering of optical fibers and placing it around the transvaginal US probe. Once the probe is in place, a laser is then turned on and the light from the laser is absorbed by the tumor, producing sound waves. This reveals information about the growth and metabolism of the tumor.
The researchers found the relative total hemoglobin was almost 2-fold higher for invasive epithelial cancerous ovaries compared to normal ovaries. The average oxygen saturation of invasive epithelial cancers was 9 percent lower than ovaries that are normal or have benign tumors.
Zhu noted their technology may provide a way to improve early detection of ovarian cancer and may help patients avoid unnecessary surgeries.
“This technology can also be valuable to monitor high-risk patients who have increased risk of ovarian and breast cancers due to their genetic mutations,” Zhu said. “The current standard of care for these women is performing risk reduction surgeries to remove their ovaries at some point, which affects their quality of life and causes other health problems.”
The researchers are working on validating their pilot study results with a larger cohort.
As a senior news writer for TriMed, Subrata covers cardiology, clinical innovation and healthcare business. She has a master’s degree in communication management and 12 years of experience in journalism and public relations.