Abstract :Introduction: Here, we used the commercially available PCA3 score to test the feasibility of the
detection of prostate specific (PSA PCR positive) and prostate cancer specific (PCA3 PCR positive)
cell material in post Digital Rectal Examination (DRE) whole urine specimens.
Methods: Prospective pilot cohort study in 11 patients, who underwent EBRT or LDRbrachytherapy
for clinically localized prostate cancer. Six patients received concomitant androgen
deprivation therapy. All patients underwent regular follow-up consultations including digital rectal
examination, PSA levels and PCA3 assays.
Results: Median follow-up was 35.2 months. None of the patients developed biochemical
recurrence. Prior to treatment, prostate cell material to perform the PCA3 assay was detected in
10/11 (90.9%) patients. However, 3, 6 and 12 months post treatment cell material was detected
in only 4/11 (36.4%), 3/11 (27.3%) and in 2/11 (18.2%) patients, respectively. No PCA3 assay was
feasible thereafter.
Conclusions: In our series, the amount of detectable urinary cells dropped rapidly and was nondetectable
after 1 year post RT. Hence, urinary cell based tests like the PCA3 assay do not seem
suitable for adding valuable information to the PSA course after RT to the prostate.