New validation of blood test that can cut biopsy rates in half for patients with rising PSAs
Not yet ready for active surveillors ... maybe someday. But what about cost?
(Eric Klein, MD)
By Howard Wolinsky
IsoPSA, a new blood test aimed at patients with rising PSAs developed at the Cleveland Clinic, continues to make ground..
Routine use of IsoPSA in patients who have not been diagnosed with prostate cancer could result in a substantial reduction of unnecessary biopsies and improve the risk-benefit ratio for prostate cancer early detection, researchers led by Eric Klein, MD, of Cleveland Clinic, reported Aug. 23 in Urologic Oncology: Seminars and Original Investigations.
For now, IsoPSA is only aimed at patients whose doctors suspect the presence of prostate cancer based on PSAs rising to 4 mg/mL and above.
Klein told The Active Surveillor that his group’s new study validates IsoPSA for patients 50 and above “with a suspicion of prostate cancer based on PSA more than 4 (and up to 100).”
The new prospective study was of 888 men scheduled for prostate biopsy at eight academic and community sites between August 2015 and August 2020.
“IsoPSA outperformed total PSA and % free PSA…” researchers said. ”IsoPSA has the potential to reduce unnecessary biopsies and improve the risk-benefit ratio for [prostate cancer] early detection.”
IsoPSA helped 42% of patients avoid biopsies.
Earlier testing showed even stronger results: IsoPSA reduced the biopsy rate by 55% and eliminated the need for mpMRIs by 9% in a study at the Glickman Urological and Kidney Institute that involved test ordering and recommendations by general urologists, fellowship-trained urologic oncologists, and advanced practice providers.
The new study represents continued good news for what appears to be a revolutionary test.
How is IsoPSA different from regular PSAs, phi, and 4Kscore tests that measure the concentration of PSA in the blood, a possible sign of prostate cancer..
IsoForm is more dynamic than other types of PSA. The test measures all the variations or isoforms--dozens, maybe hundreds-- in the blood, increasing its accuracy. Unlike standard PSA tests, which assess the blood concentration of this protein, the IsoPSA test detects cancer by identifying cancer-related structural changes in PSA.
I first covered IsoPSA in April. For more information go to:
IsoPSA is available as a pre-biopsy blood test from Cleveland Diagnostics for about $400.
Under the rules of the Food and Drug Administration, IsoPSA is considered a laboratory-developed test (LDT), a type of in vitro diagnostic test designed, manufactured, and used within a single laboratory. FDA designated IsoPSA as an LDT in 2019.
Klein stressed: “It is not validated for men with cancer or those on active surveillance. Studies to come include active surveillance patients and as a screening test in the general population.”
I know that some of you on AS already have recruited your docs and have ordered IsoPSA. Check out Louie’s story: https://howardwolinsky.substack.com/p/more-tales-of-low-risk-prostate-cancer
Meanwhile, some questions are being raised about the $400 price for IsoPSA. That’s pretty steep compared with the typical $100 PSA test. Insurance usually covers PSA, but not IsoPSA.
Will insurers pay for IsoPSA? Will they be penny-wise or pound-foolish?
IsoPSA testing potentially could be a bargain compared with a prostate biopsy, which can carry risks of costly and potentially deadly infection as well as hospitalization.
Amino, an employee benefits program, found that “the median network rate for a prostate biopsy is $877, but costs range across the U.S. from $407 to $2,585—a huge difference.”
Klein is hopeful by year’s end that the FDA will approve IsoPSA as a diagnostic, which will make it available far more easily and widely.
Availability of IsoPSA would be a huge deal for those patients who have PSAs in the grey zone of 4-10 and haven’t been diagnosed. It could spare many men from biopsies and from being diagnosed with low-grade cancers and the ritual of AS: regular MRIs, biopsies, digital rectal exams, and urologist visits.
Say tuned.
AnCan’s Virtual Support Group for Patients on Active Surveillance is holding a program, “Prostate Cancer Biopsies...The Great Debate,” on whether transrectal biopsies or transperineal biopsies are better for patients.
The program will be 8-9:30 p.m. Eastern on August 29. Register here: https://bit.ly/3OJ9Mmu
Deborah Kaye, MD, Assistant Professor Duke UniversityDivision of Urology and Duke Clinical Research Institute Margolis Policy Center, will argue for transrectal biopsies.
Arvin George, MD, a urologic surgeon specializing in the diagnosis and management of genitourinary cancers at the University of Michigan Health, will argue for transperineal procedures.
Co-sponsors include ASPI, Prostate Cancer Support Canada, the Prostate Forum of Orange County, and TheActiveSurveillor.com.
Please submit questions in advance to moderator Joe Gallo at joeg@ancan.org
Very interesting. Is there a summary of all the forms of diagnostic tests that have the potential for men to avoid a biopsy?
Tale a look at this: https://www.prostatemarkers.org/map
Various tets may help in the biopsy decision in different situations like PHI.
IspPSA is aimed at men who have no been diagnosed.