Summary & Overview
CPT 0359U: IsoPSA Prostate PSA Isoform Risk Score
CPT code 0359U designates IsoPSA®, a Proprietary Laboratory Analyses (PLA) assay from Cleveland Diagnostics Inc. that measures structural isoforms of prostate-specific antigen (PSA) in plasma and produces an algorithmic risk score for high-grade prostate cancer. The code is clinically significant because it targets PSA variants that improve specificity for clinically important prostate cancer compared with total PSA alone, affecting diagnostic pathways and downstream use of imaging and biopsy nationally.
Key payers featured include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare and Medicare. Readers will find a concise national overview of coverage patterns and benchmarks, clinical context about the assay’s role in prostate cancer risk stratification, and a summary of coding and billing considerations tied to PLA-designated tests. The publication highlights where 0359U fits in lab-based prostate cancer assessment algorithms, typical sites of service, and practical implications for laboratory and payer workflows.
This analysis is aimed at clinicians, laboratory directors, and payer policy teams seeking a clear, neutral briefing on the code’s clinical purpose, expected use cases, and the types of policy and reimbursement topics that commonly arise with PLA molecular diagnostics.
Billing Code Overview
CPT code 0359U is a Proprietary Laboratory Analyses (PLA) code that applies only to IsoPSA® from Cleveland Diagnostics Inc. The test measures cancer-related structural isoforms (variants) of prostate specific antigen (PSA) in a plasma specimen and uses an algorithmic analysis to report a risk score for high-grade prostate cancer. This assay provides a more specific marker for high-grade prostate cancer than a total PSA test.
Service type: Laboratory — Proprietary molecular diagnostic assay
Typical site of service: Clinical laboratory or reference laboratory using plasma specimens
Clinical & Coding Specifications
Clinical Context
A typical patient is a male aged 50–75 with an elevated or rising prostate specific antigen (PSA) level, prior negative or indeterminate prostate imaging, or a clinically concerning digital rectal exam. The clinician orders 0359U (IsoPSA®) when there is diagnostic uncertainty about the presence of clinically significant (high‑grade) prostate cancer and a more specific biomarker is desired to refine risk of aggressive disease.
Workflow: The patient presents to a urology clinic or primary care office with an abnormal screening PSA or symptoms suggestive of prostate pathology. A venous blood sample (plasma) is collected during the visit and sent to Cleveland Diagnostics Inc. using the manufacturer’s specimen handling instructions. The laboratory performs isoform separation and algorithmic analysis to generate a risk score for high‑grade prostate cancer. Results are returned to the ordering provider and integrated into the chart; the score is used alongside clinical data, imaging (such as multiparametric MRI), and biopsy considerations to inform shared decision‑making about surveillance, further imaging, or prostate biopsy. Typical sites of service include outpatient clinics, hospital outpatient labs, and reference laboratory facilities.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the physician interpretation component if applicable and the lab separates technical and professional components. |