PCA3/KLK3 (prostate cancer antigen 3 [non-protein coding]/kallikrein-related peptidase 3 [prostate specific antigen]) ratio (eg, prostate cancer)
CPT4 code
Name of the Procedure:
PCA3/KLK3 Ratio Test (Prostate Cancer Antigen 3 [non-protein coding]/Kallikrein-Related Peptidase 3 [Prostate Specific Antigen] Ratio)
Summary
The PCA3/KLK3 ratio test is a diagnostic blood and urine test used to evaluate the risk and presence of prostate cancer. It measures the levels of PCA3 mRNA and PSA (Prostate Specific Antigen) from collected samples to help in the early detection and diagnosis of prostate cancer.
Purpose
This test addresses the need for more accurate diagnostics to discern the likelihood of prostate cancer in patients who present related symptoms or have elevated PSA levels. The goal is to assess whether a prostate biopsy is necessary based on the PCA3/KLK3 ratio.
Indications
- Elevated PSA levels.
- Abnormal digital rectal exam results.
- Family history of prostate cancer.
- Symptoms such as difficulty urinating, blood in urine, or pelvic discomfort.
Preparation
Patients may be advised to avoid ejaculation for 48 hours prior to the test. They should inform their healthcare provider about all medications they are taking, as some may need to be adjusted.
Procedure Description
Sample Collection:
- Blood sample for PSA measurement.
- Urine sample for PCA3 mRNA measurement.
Laboratory Analysis:
- PSA level is measured from the blood sample.
- PCA3 mRNA level is measured from the urine sample.
Ratio Calculation:
- The results are used to calculate the PCA3/PSA ratio.
No anesthesia or sedation is required for this non-invasive test.
Duration
The sample collection takes about 20 minutes. Laboratory analysis and reporting usually take a few days.
Setting
The procedure is typically performed in an outpatient clinic, hospital, or diagnostic laboratory.
Personnel
- Phlebotomist or nurse for blood sample collection.
- Laboratory technician for urine sample processing.
- Urologist or oncologist for interpreting the results.
Risks and Complications
- Mild discomfort or bruising from the blood draw.
Urine collection may cause minor inconvenience.
Rarely, there might be:
- Hematoma at the blood draw site.
- Faintness or dizziness following the blood draw.
Benefits
- Non-invasive and easy to perform.
- Provides additional information to guide decision-making regarding prostate biopsies.
- Helps in identifying patients who may not need immediate biopsy, reducing unnecessary procedures.
Recovery
No specific recovery is needed. Patients can resume normal activities immediately after sample collection.
Alternatives
- MRI or ultrasound of the prostate.
- Direct biopsy of the prostate.
- Discerning between these options depends on individual patient conditions and discussion with a healthcare provider.
Patient Experience
During the procedure, patients might experience a minor discomfort from the blood draw. After the collection, no restrictions are required, and normal activities can be resumed instantly. Pain is typically not involved, requiring no specific pain management measures.