Researchers are calling for an expansion of molecular imaging in precision cancer care. Left, image of pre-therapy PET scan, right, image after three days of treatment. Penn Medicine
PHILADELPHIA, Dec. 29 (UPI) -- Researchers from the University of Pennsylvania are calling for more widespread use of molecular imaging to diagnose and treat cancer.
Molecular imaging technology uses special imaging "probe" compounds -- injected into the patient -- to highlight a particular molecular target in tissue.
FDG-PET, a molecular imaging technique used in oncology, uses a glucose-like probe called FDG, with a radioactive isotope of fluorine attached as a beacon. When injected into the bloodstream, the FDG accumulates in the tumor, lighting up the tumor on the scan.
While FDG-PET has been used for more than 20 years to detect tumors and the spread of cancer, the newer PET could reveal receptors or other tumor-related markers at locations where cancer may have spread, including in bone, which is difficult to biopsy.
These molecular imaging technologies may make it easier to diagnose, monitor and treat cancer while avoiding therapies that might prove ineffective or that have significant side effects.
According to Dr. David A. Mankoff, Ph.D., the Gerd Muehllehner Professor of Radiology and director of the PET Center at the Perelman School of Medicine at the University of Pennsylvania and lead author of the study, there are four areas where molecular imaging can have a significant impact.
Molecular imaging can help identify patients that would benefit the most from targeted therapy.
"Once we start treatment, it can also help us plan radiotherapy treatment and help define the boundaries of the active tumor," Mankoff said in a press release.
Molecular imaging can monitor the movement of drugs throughout the body to guide drug dosing and minimize side effects. The imaging can also determine whether drugs are effective and use the findings to predict patient outcomes and survival rates.
"Many of these methods are already being studied in clinical trials, but the path from clinical trials to routine clinical use is seldom easy," Mankoff said. "And molecular imaging methods face some particularly challenging hurdles such as the need to deliver the short-lived imaging probes to centers performing the imaging."
Two new classes of PET probes are designed to bind to estrogen and HER2 receptors found in breast, uterine and ovarian tumors.
In a recent trial, the combination of FDG and HER2-targeted PET imaging was 100 percent accurate in predicting patient responses to an expensive new anti-HER2 breast cancer drug.
"In that case, molecular imaging could have directed treatment to patients highly likely to benefit and spared many other patients the toxic effects and costs of ineffective therapy," Mankoff said.
The study, which concluded that testing of new imaging methods should focus on applications where they clearly represent an advance for patients over other types of imaging or biopsy, was published in JAMA Oncology.