The Application Of PCA3Score To Diagnose Prostate Cancer

Objective:1. To investigate on patients with prostate cancer and benign prostatic hyperplasia in urinary PCA3mRNA expression level relatively, and the application value of the urinary PC A3score in the diagnosis of prostate cancer.2. Different PCA3score in urine of cutoff value for suspected patients with prostate cancer diagnosis application value.3. To investigate the relationship between PCA3score with pathologic stage prostate cancer and its significance in the treatment of prostate cancer and monitoring.Methods:Cases were obtained from men with increased serum total prostate specific antigen and/or abnormal digital rectal examination before transrectal prostate needle biopsy between December2011and March2013in the second hospital of tianjin medical university. Using cell separation, RNA extraction, RT-PCR, agarose gel electrophoresis and real-time quantitative PCA technology to detect PSA and PCA3mRNA expression of urinary sediment and determinate PCA3score of urine before biopsy. Compared with biopsy pathology results using ROC curve to analyze tPSA,%f/PSA and PCA3score on the accuracy of the diagnosis of prostate cancer.To compare different PCA3score cutoff value for diagnosis prostate cancer, and determine the best cutoff value.Analysis the correlation between urinary PCA3score and Gleason score, to explore significance of PCA3score in prostate cancer treatment and monitoring.Results:1. This study collected urine specimens from153patients.123cases (80.4%) were successfully isolated urinary exfoliated cells of the prostate from suspected of prostate cancer patients, and successfully tested the PSA and PCA3mRNA content before biopsy.32cases of prostate cancer confirmed by biopsy,benign prostate hyperplasia were91cases.Prostate cancer group age52～88years old(mean69);PSA:6.9～40.8ng/ml,(meanl2.7ng/ml).Benign prostate hyperplasia group aged57～86years old (mean65);PSA:6.0～36.5ng/ml,(mean7.6ng/ml). In patients with prostate cancer PCA3mRNA expression level relatively is high in patients with benign prostatic hyperplasia and the difference is statistically significant. In urinary PC A3score averaged63+71prostate cancer patients, patients with hyperplasia of prostate in urinary PC A3score averaged24±27.Prostate cancer group PCA3score significantly higher than the hyperplasia of prostate, and statistically significant difference (P<0.01). Using ROC curve comparison tPSA,%f/PSA and PCA3score on the accuracy of the diagnosis of prostate cancer. PCA3score ROC-AUC=0.734(95%CI:0.656～0.811), PSA ROC-AUC=0.606(95%CI:0.526～0.526).The diagnostic accuracy of PCA3score better than PSA, with significant difference statistically significant (P<0.05);%f/PSAROC-AUC=0.621(95%CI:0.552～0.552).The diagnostic accuracy of PCA3score better than%f/PSA, with significant difference statistically significant (P<0.05).2. Prostate cancer confirmed by biopsy32cases,91cases of benign prostate hyperplasia.When the PCA3cutoff respectively take35,50, the sensitivity was78.1%,65.5%, specificity was69.8%,82.1%, positive predictive value were52.1%,59.7%, negative predictive value were87.7%,83.4%, PCA3test accuracy rate were72.8%and75.6%, respectively.When setting the PCA3score of cutoff value of35,48cases (52.7%)cases can avoid unnecessary biopsy,8.8%(8cases) were missed diagnosis (were missed diagnosis are low-risk prostate cancer). When setting the PCA3score cutoff value of50,66cases (72.5%) patients can avoid unnecessary biopsy, but13.2%(12cases) were missed diagnosis, and2cases (16.7%) are high risk prostate cancer.Results show that the PC A3score35is the best cutoff value, it can reduce more unnecessary puncture, also won’t miss the high risk patients in diagnosis of prostate cancer.And in the PSA level4-10ng/ml range, PCA3score35still has high diagnostic accuracy, its diagnostic sensitivity and specificity were76.6%and64.5%, respectively.3. The biopsy results show Gleason score<7group of15patients, Gleason score7or higher group of17cases of patients, in different Gleason scores of prostate cancer patients PCA3score is different Comparison results show that the Gleason score7or higher group PC A3score was81±89;<7group of56±61. The difference between the two groups was statistically significant (P<0.05), and there is positive correlation trend (P<0.05). This suggests that the Gleason scores of prostate cancer may be associated with PCA3gene expression.Conclusion:1. Prostate cancer patients urine specimen PCA3mRNA expression level higher than PCA3mRNA in patients with benign prostatic hyperplasia urine specimen. Prostate cancer patients group average PCA3score significantly higher than the hyperplasia of prostate.2. Compared with PSA, urinary PCA3score sensitivity is a bit low, but has good specificity and positive predictive value, and between the gray area in PSA4～10ng/ml the biopsy results the positive rate is low, urinary PCA3score in the diagnosis of PCa specificity of64.5%. It probably can help determine whether need to biopsy, and increase the biopsy positive rate.PCA3score of the detection rate of prostate cancer is significantly higher than PSA for the detection of prostate cancer by ROC curve analysis. PCA3score prediction for the biopsy results than PSA, it may be ideal tumor-specific markers of prostate cancer, and it’s can reduce unnecessary prostate biopsy.3. The high-risk group of prostate cancer in the PC A3score higher than in low-risk prostate cancer group PCA3score, and the PCA3score was a positive correlation with Gleason scores of prostate cancer. This suggests that the Gleason scores of prostate cancer may be associated with PCA3gene expression, detecting PCA3score is expected to become a good indicator of PCa treatment monitoring.