Prostate Specific Antigen (PSA), Free
CPT Code(s):
84154
Turnaround Time:
4 hours
Specimen Requirements
Preferred Specimen:
Serum
Minimum Volume:
1.0 mL
Transport Container:
Serum Separator Tube (SST) or Red Top Tube
Transport Temperature:
Room Temperature
Collection Instructions:
Allow blood to clot completely prior to centrifugation. Separate serum from cells within 45 minutes of collection. Protect from light during collection and storage
Rejection Criteria:
Plasma specimen; gross hemolysis; lipemia; improper labeling
Stability Criteria
Room Temperature:
8 hours
Refrigerated:
5 days
Frozen:
90 days
Clinical Significance
The Free Prostate-Specific Antigen (PSA) test holds specific clinical significance and diagnostic use in the evaluation of prostate health and the detection of prostate cancer. PSA is a protein produced by the prostate gland, and its levels in the blood can be measured through various tests, including Total PSA and Free PSAs.
The specific clinical significance and diagnostic use of Free PSA include:
1. Differentiating Prostate Cancer: Free PSA aids in the differentiation between benign prostatic conditions and prostate cancer. Prostate cancer is often associated with an increased ratio of Total PSA to Free PSA. A lower percentage of Free PSA may suggest a higher likelihood of prostate cancer, while a higher percentage indicates a lower risk. Free PSA helps refine the assessment of prostate cancer risk, particularly in cases where the Total PSA level is moderately elevated.
2. Risk Stratification: Free PSA is utilized to stratify the risk of prostate cancer in patients with borderline or moderately elevated Total PSA levels. By considering the percentage of Free PSA in relation to Total PSA, healthcare providers can better determine the need for further diagnostic tests, such as prostate biopsy, in order to make informed decisions about the management and treatment of patients.
3. Monitoring Disease Progression: For patients diagnosed with prostate cancer, serial measurements of Free PSA can be used to monitor disease progression and treatment response. Changes in Free PSA levels over time may indicate the effectiveness of treatment interventions or the need for adjustment of therapeutic approaches.
4. Individualized Treatment Decisions: Free PSA contributes to individualized treatment decisions in prostate cancer patients. By considering both Total PSA and Free PSA levels, healthcare providers can better assess disease aggressiveness and tailor treatment plans accordingly. Patients with a lower percentage of Free PSA may be recommended for additional diagnostic tests or more aggressive treatment approaches.
It is important to note that Free PSA is not used as a stand-alone diagnostic tool but as a complementary test to Total PSA. It provides additional information to assist healthcare providers in making more accurate assessments and decisions related to prostate health.
In summary, Free PSA has specific clinical significance in differentiating prostate cancer from benign prostatic conditions, risk stratification, monitoring disease progression, and aiding in individualized treatment decisions. By assessing the percentage of Free PSA in relation to Total PSA, this test provides valuable information for clinical decision-making, optimizing patient care outcomes, and improving the early detection and management of prostate cancer.