A multi-center study by New York Presbyterian/Columbia University Medical Center found a urine test can determine if a patient has high-grade prostate cancer with 92% accuracy. The findings were presented at the AUA 2015 Annual Meeting. This study could present a breakthrough in how doctors screen for prostate cancer.
The hope is that the test will replace traditional invasive surgical biopsies, which often require patients to be tested more than once.
The study analyzed 1600 men over 50 years old with no history of prostate cancer across the 25 urology practices in the U.S.
All the men had been told previously by a urologist that they needed a biopsy. Men had a PSA 2-10 ng/mL. Their urine was sampled with a new test awaiting FDA approval called Exo106, added to the current prognostic standard of care (SOC) (age, race, PSA, family history).
- Focuses on exosomes: small organelles containing RNA that can be tested for cancer genes
- Known as liquid biopsy
- A negative predictive test
- First exosomal RNA test for cancer in humans
- Not FDA approved, still in trial stages
- Offers clear advantages over traditional needle biopsy
- Analyzes exosomal RNA for three biomarkers known to be expressed in men with high-grade prostate cancer.
- Using a proprietary algorithm that integrates this three-gene signature, the test assigns an individualized risk score for patients that predicts the presence of high-grade (Gleason Score ≥ 7) prostate cancer.
- Test is meant for men 50 or older with a PSA 2-10ng/mL
- Simple urine sample without a DRE
- Other liquid biopsy tests on the market require a DRE
Traditional needle biopsies are invasive and can have false positives and negatives due to difficult in separating high-grade prostate cancer from other forms.
This test was able to predict high-grade prostate cancer biopsy results with a 91.9% sensitivity —Sensitivity (also called true positive rate) measures percentage of high-grade prostate cancer.
Significantly improved the ability to accurately predict high-grade prostate cancer in men who need an initial biopsy.
Researchers are predicting that the adoption of Exo106 should result in a 27% reduction of prostate needle biopsies
About Exosome Diagnostics
Exosome Diagnostics is a company that developed the Exo106 prostate cancer liquid biopsy test and also developer of revolutionary biofluid-based molecular diagnostics. Exosome Diagnostics is developing a non-invasive urine-based liquid biopsy test to predict the aggressiveness of prostate cancer prior to initial tissue biopsy.
The test is being designed to enable physicians for more accurate diagnosis on an initial biopsy. In 2015, plans to conduct additional studies including outcomes and economic studies for the liquid biopsy test. Plans to proceed with a commercial launch of laboratory developed test in US in 2016. Also pursuing approval of an in vitro diagnostic version of the test with the FDA.
The company has also developed a sophisticated economic model that calculates the expected cost savings health plans by incorporating this test into prostate cancer screening, diagnosis. Estimates national health plans (15 million members) could save approx. $166 million per year with full adoption. Regional health plans (2.5 million members) could save approx. $29 million per year with full adoption.
Current Screening for Prostate Cancer
- Issue: Unnecessary biopsies leading to overtreatment
- PSA has a high false positive rate and high false negative rate
- PSA is a non-specific test to prostate cancer
- PSA cannot differentiate between high/low grade prostate cancer
- A major need for pre-biopsy diagnostic tools that can accurately identify high-grade prostate cancer that needs immediate intervention
- Current diagnostic standard of care for prostate cancer is widespread thought to be imprecise
- Liquid biopsies
- Emerging class of diagnostics
- Designed to reveal molecular information about cancer and non-invasively from biofluids such as urine or blood plasma
- Avoid need for direct access to cancerous tissue
- Prostate biopsies
- More than 1 million biopsies are performed each year in US
- # of positive biopsies is increased
- Only 25% of men who have a prostate biopsy due to an elevated PSA have high-grade prostate cancer
- Remaining 75% have low-grade pc that may remain indolent
- Traditional needle biopsies can have complications like infection
- Cost of unnecessary biopsies in US = $1.3 billion
- Despite high prevalence of low-risk pc, approx. 50% of men are still treated with surgery or radiation at diagnosis
- Aggressive treatment is often associated with significant long-term complications including impotence and incontinence