Dynamic Contrast Enhanced Magnetic Resonance Imaging Improves Classification of Prostate Lesions: A Study of Pathological Outcomes on Targeted Prostate Biopsy.

PURPOSE: PI-RADS™, version 2 stipulates that dynamic contrast enhanced imaging should be used to classify diffusion-weighted imaging score 3 peripheral zone lesions as PI-RADS score 3 (dynamic contrast enhanced imaging negative or nonenhancing) or 4 (dynamic contrast enhanced imaging positive or enhancing). However, to our knowledge it is unknown whether dynamic contrast enhanced imaging separates lesions into clinically meaningful pathological groups. We examined whether dynamic contrast enhanced imaging would improve the detection of clinically significant cancer. MATERIALS AND METHODS: We identified patients without a prior diagnosis of prostate cancer who underwent multiparametric magnetic resonance imaging-transrectal ultrasound fusion targeted biopsy of peripheral zone lesions with a diffusion-weighted imaging score of 3 or 4. Each lesion was grouped into 1 of 3 classifications, including group 1-diffusion-weighted imaging score 3/nonenhancing/PI-RADS score 3, group 2-diffusion-weighted imaging score 3/enhancing/PI-RADS score 4 or group 3-diffusion-weighted imaging score 4/PI-RADS score 4. We measured the rate of grade group 2 or greater pathology detected for each lesion group with subgroup analyses in patients with vs without prior negative systematic biopsy. RESULTS: We identified a total of 389 peripheral zone diffusion-weighted imaging score 3 or 4 lesions in 290 patients. The rate of grade group 2 or greater cancer on biopsy for group 1, 2 and 3 lesions was 8.9%, 21% and 36.5%, respectively (p <0.03). The rate of grade group 2 or greater pathology was higher in group 2 than group 1 lesions in patients with prior negative systematic prostate biopsy (28% vs 5.0%, p <0.001) but not in those without such a biopsy (16% vs 12%, p = 0.5). Group 3 lesions had a higher rate of grade group 2 or greater cancer than group 2 lesions in the biopsy naïve subgroup (46% vs 16%, p = 0.001). However, the rates were similar in patients with prior negative systematic prostate biopsy (27% vs 28%, p = 0.9). CONCLUSIONS: Diffusion-weighted imaging score 3 peripheral zone lesions were more likely to be clinically significant cancer (grade group 2 or greater) if they were dynamic contrast enhanced T1-weighted imaging positive. That was most apparent in patients with a prior negative systematic prostate biopsy. In such patients including a dynamic contrast enhanced sequence in multiparametric magnetic resonance imaging allowed for optimal lesion risk stratification.

Prostate Health Index density improves detection of clinically significant prostate cancer.

OBJECTIVES: To explore the utility of Prostate Health Index (PHI) density for the detection of clinically significant prostate cancer (PCa) in a contemporary cohort of men presenting for diagnostic evaluation of PCa. PATIENTS AND METHODS: The study cohort included patients with elevated prostate-specific antigen (PSA; >2 ng/mL) and negative digital rectal examination who underwent PHI testing and prostate biopsy at our institution in 2015. Serum markers were prospectively measured per standard clinical pathway. PHI was calculated as ([{-2}proPSA/free PSA] × [PSA]½ ), and density calculations were performed using prostate volume as determined by transrectal ultrasonography. Logistic regression was used to assess the ability of serum markers to predict clinically significant PCa, defined as any Gleason score ≥7 cancer or Gleason score 6 cancer in >2 cores or >50% of any positive core. RESULTS: Of 118 men with PHI testing who underwent biopsy, 47 (39.8%) were found to have clinically significant PCa on biopsy. The median (interquartile range [IQR]) PHI density was 0.70 (0.43-1.21), and was 0.53 (0.36-0.75) in men with negative biopsy or clinically insignificant PCa and 1.21 (0.74-1.88) in men with clinically significant PCa (P < 0.001). Clinically significant PCa was detected in 3.6% of men in the first quartile of PHI density (<0.43), 36.7% of men in the IQR of PHI density (0.43-1.21), and 80.0% of men with PHI density >1.21 (P < 0.001). Using a threshold of 0.43, PHI density was 97.9% sensitive and 38.0% specific for clinically significant PCa, and 100% sensitive for Gleason score ≥7 disease. Compared with PSA (area under the curve [AUC] 0.52), PSA density (AUC 0.70), %free PSA (AUC 0.75), the product of %free PSA and prostate volume (AUC 0.79), and PHI (AUC 0.76), PHI density had the highest discriminative ability for clinically significant PCa (AUC 0.84). CONCLUSIONS: Based on the present prospective single-centre experience, PHI density could be used to avoid 38% of unnecessary biopsies, while failing to detect only 2% of clinically significant cancers.

Elevated Prostate Health Index (phi) and Biopsy Reclassification During Active Surveillance of Prostate Cancer.

The Prostate Health Index (phi) has been FDA approved for decision-making regarding prostate biopsy. Phi has additionally been shown to positively correlate with tumor volume, extraprostatic disease and higher Gleason grade tumors. Here we describe a case in which an elevated phi encouraged biopsy of a gentleman undergoing active surveillance leading to reclassification of his disease as high risk prostate cancer.