APTIMA PCA3 Molecular Urine Test: Development of a Method to Aid in the Diagnosis of Prostate Cancer

Abstract

Background: Prostate cancer gene 3 (PCA3) encodes a prostate-specific mRNA that has shown promise as a prostate cancer diagnostic tool. This report describes the characterization of a prototype quantitative PCA3-based test for whole urine. Methods: Whole-urine specimens were collected after digital rectal examination from 3 groups: men scheduled for prostate biopsy (n ‫؍‬ 70), healthy men (<45 years of age with no known prostate cancer risk factors; n ‫؍‬ 52), and men who had undergone radical prostatectomy (n ‫؍‬ 21). PCA3 and prostate-specific antigen (PSA) mRNAs were isolated, amplified, and quantified by use of Gen-Probe DTS400 ® Systems. Prostate biopsy results were correlated with the PCA3/PSA mRNA ratio, and PSA mRNA concentrations were used to normalize PCA3 signals and confirm the yield of prostate-specific RNA. Assay precision, specimen stability, and mRNA yield were also evaluated. Results: The specimen informative rate (fraction of specimens yielding sufficient RNA for analysis) was 98.2%. In this clinical research study, ROC curve analysis of prebiopsy specimens yielded an area under the curve of 0.746; sensitivity was 69% and specificity 79%. Serum PSA assay specificity was 28% for this same group. PCA3 and PSA mRNAs were undetectable in postprostatectomy specimens except for one man with recurrent prostate cancer. Assay interrun CVs were

Identification of PCA3 (DD3) in prostatic carcinoma by in situ hybridization

“…A newly developed research-use only urine test detecting PCA3 RNA in urine (Aptima PCA3, Gen-Probe Inc., San Diego, CA, USA) showed a global sensitivity and specificity of 69 and 79%, respectively. 27 However, no study published to date has attempted to localize the marker in tissue sections. Our study showed for the first time a sensitivity of 92-93% for PCA3 to detect prostate cancer on tissue sections, using either a radioactive or a nonradioactive method.…”

Efforts to resolve the contradictions in early diagnosis of prostate cancer: a comparison of different algorithms of sarcosine in urine

“…Between February and August 2010, a total of 110 consecutive patients with PSA44 ng ml À1 or abnormal digital rectal examination, out of which 71 patients with PCa and 39 patients with no evidence of malignancy (NEM), as confirmed by 10 core prostate biopsy samples at Shanghai Cancer Center (Shanghai, China), were enrolled. At the time of enrollment and at 1 week later, the first-void urines from these 110 patients were collected, respectively, after standardized digital rectal examination 17 in about 5 min. The second-morning void urines from 20 healthy men and women were also obtained.…”

PCA3 score and prostate cancer diagnosis at repeated saturation biopsy. Which cut-off: 20 or 35?

“…Gleason score (GS) was 6 in 26 cases (81.2%), 7 in 4 (12.5%) and 8 in 2 (6.3%). Median positive cores were 2 (range: [1][2][3][4][5][6][7][8][9][10][11][12][13][14] with the presence of either only one positive Diagnostic accuracy, sensitivity, specificity, PPV and NPV of PCA3 score cut-off of 20 vs 35 are listed in Table-1. ROC analysis demonstrated an AUC for PCA3 ≥ 20 vs PCA3 ≥ 35 of 0.678 and 0.634, respectively.…”

“…From three to ten days prior to performing SPBx, first-catch urine samples were collected following digital rectal examination (three strokes per lobe) and processed to quantify PCA3 and PSA mRNA concentrations using the PROGENSA PCA3 assay (Gen-Prob Inc. San Diego, CA USA); PCA3 score was calculated using the following equation: (PCA3 mRNA/PSA mRNA) x 1000 (13).…”