The Food and Drug Administration (FDA) has approved a novel method of identifying prostate cancer cells that have metastasized to other organs, reports The New York Times. Thirty years in the making, the test may soon improve prostate cancer treatment.

Prostate cancer is most common in men over age 65, especially those with a family history of or a genetic predisposition to the disease. In any given year, 174,600 men in the United States will be diagnosed with prostate cancer and 31,600 will die of it. The prevalence of the disease has made its prevention and treatment an oncological priority.

By making prostate cancer cells beam on a PET scan, the new test identifies whether metastasis has occurred and if so, where. The ability to access a visual representation of cancer metastases can increase the specificity of treatment, allowing doctors to rely on targeted radiation for

“It’s the most exciting thing in prostate cancer in my lifetime,” Kirsten Greene, MD, the chair of the urology department at the University of Virginia School of Medicine, told the Times.

The test has roots in a discovery made almost three decades ago. In the 1990s, cancer researchers found that prostate cancer cells express a distinct protein on their surfaces that can be detected by small molecules. Recognizing the potential significance of this physiological quirk, they began designing a test that would use those molecules to find prostate cancer cells hiding in distant tissues. In studies conducted at UCLA and UCSF over the past few years, the test proved able to pinpoint prostate cancer cells both before and after treatment.

“It’s absolutely fabulous,” A. Oliver Sartor, MD, a professor of medicine at Tulane University School of Medicine, said. He greeted the news of the test’s approval with a jig in his office and “a toast of imaginary champagne,” he said.

Until this test becomes widely available, doctors will in some ways be flying blind. While blood tests can diagnose prostate cancer by flagging high levels of the protein prostate-specific antigen (PSA), they cannot identify the exact location of the cancer cells—meaning whether they confined to the prostate or have already metastasized. An MRI can provide some evidence of metastasis, but in many cases, the only option is to treat first—which may include a prostatectomy to remove the prostate partially or entirely—and then check PSA levels to see whether the cancer has recurred.

The FDA’s approval currently extends only to testing at UCLA and UCSF, both of which are currently conducting research on how the new medical innovation affects patient survival duration. But several companies hope to market the new test more widely and maybe even rejigger it to deliver drugs to prostate cancer cells directly.

To learn more about this test, read “PSMA PET-CT Accurately Detects Prostate Cancer Spread, Trial Shows.” And to read about another innovation in prostate cancer treatment, see “Minimally Invasive Ultrasound Ablation Can Treat Prostate Cancer.”