Entering the new era of molecular diagnostics, the lab is offering tests once available only at major academic medical centers. As a result, our physicians and patients are able to undertake treatment plans with a greater degree of certainty.
In 1990, the year before PSA screening came into use, about 45,000 men died of prostate cancer. Last year, fewer than 30,000 men died of prostate cancer. “Clearly, the PSA test and improved treatment have lowered the death rate by a third,” says Dr. Evan Goldfischer, co-CEO of Premier Medical Group. “However, we have probably over-treated some patients, removed prostates that didn’t need to be treated and diagnosed people that perhaps didn’t need to be diagnosed. A number of genetic markers that have only recently become available give us the opportunity to refine our techniques.”
There are four molecular tests being operationalized at Premier to enhance physicians’ decisions on who to treat. No single test provides enough information, in itself, to drive a patient’s care, but the additional data gives doctors and patients a better understanding of whether a negative biopsy is truly negative— roughly 25 percent of these are false-negatives—or, in the case of a positive biopsy, to have a better sense of whether a patient has the aggressive, life-threatening form of cancer that warrants immediate treatment. “Our goal is to decrease the number of biopsies performed and the number of patients who receive treatment when active surveillance might be more appropriate,” says Goldfischer.
Testing in the new era of molecular diagnostics
• The Prostate Cancer Antigen 3 Assay (PCA3), an automated molecular test, was approved by the FDA in 2012. The PCA3 gene is highly overexpressed in the urine of men with prostate cancer. “If you get a high PCA3 score,” Goldfischer says, “that tells you that there may be cancer that didn’t show up in the biopsy, while a low score suggests a repeat biopsy may not be indicated.”
• ConfirmMDx is a test performed on left-over tissue from a negative biopsy. “We know that cancer in the prostate leads to the biochemical process of DNA methylation, what we call a halo effect. “If the test finds DNA methylation, that suggests that some small cancer may be present, that it needs to be watched closely and maybe the patient needs a repeat biopsy,” says Goldfischer. “It gives you a much higher likelihood of that negative being a true negative, and you can take a big sigh of relief and maybe you don’t have to undergo repeat biopsy.”
• Oncotype DX ® Prostate Cancer Assay is used for men who have been diagnosed with prostate cancer. It provides a more precise and accurate assessment of risk based on individual tumor biology. “This test tells you, if you have prostate cancer, do you have the really aggressive, life-threatening prostate cancer or a lower-grade cancer for which an active surveillance approach might be reasonable,” Goldfischer says.
• The 4Kscore™ Test, a blood test soon to join the lab’s arsenal, measures four biomarkers for prostate cancer. The results are entered into an algorithm that yields a predictive score. “Let’s say you’re a patient who has undergone a biopsy that was negative,” Goldfischer explains. “Now your PSA has gone up and you’re worried and wondering whether to have another biopsy. This blood test will give you a percentage that is the chance of your having high-grade cancer, the aggressive kind that could kill you. If the test comes back at 25 percent, well, you’ll probably want to have the biopsy. Let’s say it comes back at 5 percent, which means there is a 95 percent chance you don’t have high-grade cancer: in that case you may want to watch and wait.”
The laboratory is entering a new era of molecular diagnostics. For some time the lab has been performing the Fluorescence in situ hybridization test (FISH), mapping the genetic material in cells to detect bladder cancer. It has been using the Know Error system, employing DNA tagging to ensure there’s no mix-up in biopsy samples. Now, Premier’s lab is engaging the newest, cutting edge techniques, the approach found at academic centers and some of the larger, more progressive urology groups. The Premier lab is among the leaders of the pack.