PCA3 urinary test versus 1H-MRSI and DCEMR in the detection of prostate cancer foci in patients with biochemical alterations

Aim: To compare the prostate antigen 3 (PCA3) test with 1H-magnetic resonance spectroscopic imaging (1H-MRSI) and dynamic contrast-enhanced magnetic resonance imaging (DCEMR) combined examination in the detection of prostate tumor foci in patients with persistently elevated prostate-specific antigen (PSA) levels and prior negative random transrectal ultrasound (TRUS)-guided biopsy. Patients and Methods: Forty-three patients with a first random biopsy negative for prostate adenocarcinoma, persistent elevated PSA and negative digital rectal examination were recruited. All the patients were submitted to MRSI examination (MRSI-DCEMR) and were submitted to an attentive prostate massage in order to perform PCA3 assay. Afterwards, 10-core laterally-directed random TRUS-guided prostate biopsy was performed. Results: The overall sensitivity and specificity of a PCA3 score ≥35 for positive biopsy were 76.9% and 66.6%, respectively, with a positive predictive value (PPV) of 80% and a negative predictive value (NPV) of 625%; as for MRSI sensitivity and specificity were, respectively, 92.8% and 86.6% with a PPV of 92.8% and a NPV of 86.6%. Receiver operating characteristic (ROC) analysis rates were 0.755 for PCA3 and 0.864 for MRSI. Conclusion: Combined MRSI/DCEMR can better improve the cancer detection rate in patients with prior negative TRUS-guided biopsy and altered PSA serum levels than PCA3. Optimization of MRSI will allow more precise diagnosis of local invasion and improved bioptical procedures.