1. What is PSA Velocity?

PSA Velocity (PSAV) measures the rate of change in prostate-specific antigen (PSA) levels over time. It's calculated as the change in PSA divided by the time interval between measurements.

2. How Does the Calculator Work?

The calculator uses the PSA Velocity formula:

Where:

• \( PSAV \) — PSA Velocity (ng/mL/year)
• \( PSA_2 \) — Current PSA level (ng/mL)
• \( PSA_1 \) — Initial PSA level (ng/mL)
• \( Time \) — Time between tests (years)

Explanation: The formula calculates the annual rate of PSA change, which can help assess prostate cancer risk and progression.

3. Importance of PSA Velocity

Details: PSA Velocity is used in prostate cancer screening and monitoring. A PSAV > 0.75 ng/mL/year may indicate higher risk of prostate cancer.

4. Using the Calculator

Tips: Enter both PSA values in ng/mL and the time interval in years. All values must be valid (PSA ≥ 0, time > 0).

5. Frequently Asked Questions (FAQ)

Q1: What is a concerning PSA Velocity?
A: Generally, PSAV > 0.75 ng/mL/year may warrant further investigation, though clinical context is important.

Q2: How often should PSA be measured for velocity?
A: Typically measured over at least 12-18 months with multiple tests for reliable velocity calculation.

Q3: Are there limitations to PSA Velocity?
A: Yes, PSA can fluctuate due to non-cancer factors like infections, procedures, or benign prostate conditions.

Q4: Does PSA Velocity replace PSA level?
A: No, it's used alongside absolute PSA levels and other factors in clinical decision-making.

Q5: What if my PSA decreased over time?
A: Negative PSA Velocity values (when PSA decreases) are possible and generally not concerning.