Cleveland Diagnostics, a biotechnology company developing next-generation diagnostic tests for the early detection of cancers, today announced an agreement designed to expand patient access to Cleveland Diagnostics’ novel prostate cancer test, IsoPSA.

Through an agreement with Quest Diagnostics, a provider of diagnostic information services, patients will be able to access IsoPSA and, once ordered by their physician, provide a blood specimen for testing at one of over 2,100 Quest Diagnostics patient service center locations nationwide later this year. With its national logistics network, Quest will transport the specimens to Cleveland Diagnostics’ laboratory for testing. The parties expect physicians will be able to begin offering the test to patients through Quest Diagnostics in the second quarter of 2023.

The IsoPSA Test

IsoPSA is a blood-based prostate cancer test used in triaging patients at risk for high-grade prostate cancer to biopsy. For patients with elevated levels of prostate-specific antigen (PSA), IsoPSA provides additional insight into whether patients’ elevated PSA levels are due to high-grade cancer or a different condition, thereby empowering physicians and patients with insights for deciding whether to undergo prostate biopsy.

Further Reading: Why the Triage Approach Will Improve Cervical Cancer Screening and Diagnosis

PSA is a protein produced by cells of the prostate gland. While the PSA test measures the level of PSA in the blood, which is often elevated in people with prostate cancer, several benign conditions can also cause a person’s PSA level to rise.1 Moreover, PSA testing is unable to identify cases of prostate cancer that may be rapidly progressing and therefore require urgent treatment. By comparison, the IsoPSA test helps predict risk by interrogating the partitioning behavior of isoforms of PSA that are linked to cancer. In a large, prospective, multi-center clinical study, the IsoPSA test demonstrated significant improvement in detecting high grade prostate cancer.2 A separate and robust clinical utility study confirmed that IsoPSA could reduce unnecessary biopsies by as much as 55%.3

“We are very pleased to collaborate with Quest Diagnostics to expand patient access to IsoPSA. We believe Quest’s broad reach and extensive laboratory services expertise will provide patients and their physicians with unparalleled access to transformative clinical insights,” says Arnon Chait, CEO of Cleveland Diagnostics. “As the leader in oncology testing, Quest is aligned with Cleveland Diagnostics’ vision of providing physicians and their patients exceptional and more definitive understanding of their prostate conditions.”

According to the American Cancer Society, prostate cancer increased by 3% per year from 2014 through 2019 after two decades of decline, driven primarily by the diagnosis of advanced disease.4 A recent Quest Diagnostics Health Trends study suggests this trend could continue or even worsen: two years after the COVID-19 pandemic began, the rate of new diagnoses of prostate cancer continued to lag behind pre-pandemic levels, suggesting delays in care may contribute to more advanced prostate cancers in the future.

“Prostate cancer is a leading cause of cancer – and cancer deaths – among men, and physicians are eager for improved tools to diagnose, stage and monitor this disease,” says Kristie Dolan, vice president and general manager of Oncology at Quest Diagnostics. “We believe IsoPSA holds great promise to better inform physicians’ diagnostic and treatment decisions for their patients being evaluated for prostate cancer, and we are pleased to work with Cleveland Diagnostics to expand access to this important new test, ultimately bettering patient outcomes by improving the diagnostic process.”


1 Prostate-Specific Antigen (PSA) Test – NCI (

2 Klein E, Partin A, Lotan Y, et al. Clinical validation of IsoPSA, a single parameter, structure-focused assay for improved detection of prostate cancer: A prospective, multicenter study. Urol. Oncol.2022; 40(9): 408.e9-408e.18

3 Scovell JM, Hettel D, Abouassaly A, et al. IsoPSA® reduces recommendations for biopsy and magnetic resonance imaging in men with total PSA ≥ 4ng/ml: A real-world observational clinical utility study. Urol Pract. 2022; 9:173.

4 More men diagnosed with advanced prostate cancer as PSA testing drops (