In the test, the sample is placed in a tube containing inhibitors of ribo nucleases, otherwise the RNA would be destroyed. This sample is sent to the laboratory, where it will be analyzed.
In which cases do the PCA3 test
The performance of a urine PCA3 test is indicated in the following situations:
- Men with elevated PSA but with a first biopsy negative to cancer.
- Men with normal PSA values but with rectal testicular suspicion of cancer.
- Men with PSA elevations associated with varying degrees of prostatitis.
- Men with prostate cancer already diagnosed but who have not yet begun any treatment, in which disease progression is suspected.
- Men with a family history of prostate cancer.
The ideal PCA3 score
Level 35 was initially indicated as an ideal score for the diagnosis of prostate cancer, since it offers the best sensitivity (54%) and specificity (72%).. It offers greater diagnostic safety than the percentage of free PSA / total PSA.
In 2012, the FDA approved the use of PCA3 on the basis of clinical evidence that analyzed the case of 466 men over 50 years old with at least one negative prostate biopsy, who were offered repeat biopsy. In the PCA3 score of 25 the negative predictive value was 90%. Up to 50% of the biopsies could be avoided and 2% of tumors with Gleason 7 or higher would not have been diagnosed.
This investigation showed that men with PCA3 less than 25 were 4.6 times less likely to have a positive repeat biopsy than men with a PCA3 score greater than 35. Due to these results the cut level of the PCA3 score becomes 25. This means that men with PCA3 greater than 25 should undergo prostate biopsy to rule out the presence of cancer.
In 2013 the AUA guidelines recognized that PCA3 has a secondary testing role after PSA to diagnose prostate cancer.
High Grade Prostate Risk with 4Kscore Test
The 4Kscore Test provides an individualized risk score for high-grade prostate cancer for each patient undergoing the test, which helps the doctor determine the treatment he needs.
The 4Kscore Test has been developed for more than a decade by an expert international team of researchers. It combines data from levels of 4 substances in the blood ( total PSA, free PSA, intact PSA and human kallikrein 2 ) along with patient data relating to age, rectal examination result and previous biopsy.
These data, compared to the more than 10,000 patients evaluated in previous research, provide the physician with the individual risk outcome, helping to make the best decisions to follow the diagnostic process.
4Kscore Test Results
The result of the 4Kscore Test is easy to interpret and compare, for example: if a patient gives a 7% risk means that out of every 100 people in the same situation, only 7 will have high-grade prostate cancer and that both the remaining 93 will have a benign pathology or a low grade tumor. A result of 20% assumes that 20 out of 100 people in the same situation will have high-grade prostate cancer. As there are no indeterminate results, the information provided is always valid to aid in decision making.
Contraindications for the 4Kscore Test
A 4Ksore Test should not be performed in the following cases:
- When the patient already has a previous diagnosis of prostate cancer.
- If rectal examination has been performed within 4 days prior to blood collection.
- If you have used drugs such as Dutasteride or Finasteride in the previous 6 months.
- If the patient has undergone any treatment for benign prostatic hyperplasia in the previous 6 months such as laser, transurethral resection of the prostate (TUR), urethral catheterization or endoscopy of the lower genitourinary tract.