The Food and Drug Administration has approved a new drug to help doctors locate cancerous cells in the body during surgery. The product, a fluorescent probe called Prostracker, will help surgeons identify cancerous tissue that may not otherwise be detected in patients undergoing surgery.
Ovarian cancer affects about 21,000 American women a year, and the national survival rate is nearly eight years. The disease kills many women: in 2013, more than 50,000 women died of ovarian cancer. More than 14,000 women were diagnosed with ovarian cancer that year.
In the past, doctors often missed key tissue, such as the ovaries, that were present in tumors. According to the National Cancer Institute, the post-surgery findings typically showed no sign of ovarian cancer, but the tumors may have concealed the presence of lymph nodes. Now, Prostracker can help find those nodes and therefore potentially help patients stay clear of cancer.
The Prostracker probes are made of material that contains fluorescent molecules that can glow under a fluorescent microscope. When a doctor implants the Prostracker probes into the area around the ovaries, the probes can be illuminated and continually sent light from an electric source. The probe flashes with that light every 30 milliseconds, and then the light is taken over by a different type of light that can be used to identify tissue to see and monitor surgery. The Prostracker probes contain a dye that can be moved by a tube of the probe to work to guide the path of the probe, or can be used to guide the probe by ultrasound.
Takhar Kirpalani, a professor at the UCLA Jonsson Comprehensive Cancer Center, will be leading the clinical trial for Prostracker, which started Monday. Kirpalani conducted prior research on Prostracker’s ability to detect and track residual cancer cells. He says that the drug is already being used successfully in the body and is a tool that his team believes will help to improve cancer care.
“We have done research that showed that Prostracker can get down to the bare cell level in metastatic ovarian cancer,” Kirpalani says. “Right now, if we have images, patients can’t make out whether it’s chemotherapy. Prostracker puts you back to the original, where if you have a couple of the probes, the light goes up.”
The Prostracker probes are currently being tested on more than 90 patients at six centers across the country.