The new tracer shows tumors in a 64 year old man newly
diagnosed with prostate cancer.
Researchers at the National Institute of Biomedical Imaging and Bioengineering (NIBIB) have developed a new radiotracer to diagnose prostate cancer and conducted a successful Phase I clinical trial, published in The Journal of Nuclear Medicine.
Prostate cancer is the fifth leading cause of death worldwide and is especially difficult to diagnose. While prostate cancer is relatively easy to treat in its early stages, it is prone to metastasis and can quickly become deadly. In order to plan how aggressively they should treat the cancer, it is important for doctors to know how far the cancer has progressed. Currently, doctors use a variety of imaging techniques and tests to diagnose and monitor prostate cancer including PSA blood tests, magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), positron emission tomography (PET), and computerized tomography (CT) scans. Each method has strengths and weaknesses, but there is no single method that is able to successfully identify and monitor primary tumors, metastatic lymph nodes, and bone lesions.
|The image above shows the new tracer identifying |
prostate tumors and immunohistologic staining of
prostate tissue. Source: Xiaoyuan Chen, National
Institute of Biomedical Imaging and Bioengineering
The tracer was able to successfully identify 3 out of 4 primary tumors, all 14 metastatic lymph nodes and, significantly, was able to identity all 20 of the bone lesions in the patients. The current method of identifying bone lesions is to use the radiotracer MDP with a SPECT scanner. While this method is consistently able to identify bone lesions, it often comes up with false positives and is not able to identify primary tumors. This can cause the patient to undergo unnecessary treatments or painful biopsies.
“We are far from finding one method to diagnose and monitor prostate cancer, but this is a step in that direction,” says Chen. “Targeting multiple biomarkers could potentially allow us to identify prostate cancer at its early stages as well as after metastasis in one scan.”
Chen believes that dual-receptor targeting tracers could one day be the primary method for diagnosing and monitoring prostate cancer reducing the amount of medical scans a patient would be forced to undergo and streamlining the diagnostic and therapeutic process.