Efficacy of 3T Multiparametric MR Imaging followed by 3T in-Bore MR-Guided Biopsy for Detection of Clinically Significant Prostate Cancer Based on PIRADSv2.1 Score.

PURPOSE: To evaluate the diagnostic yield of 3T in-Bore magnetic resonance-guided biopsy (3T IB-MRGB) for detection of clinically significant prostate cancer (csPCa), based on assessment using the Prostate Imaging Reporting and Data System version 2.1 (PIRADSv2.1). MATERIALS AND METHODS: This single-center study examined individuals who underwent 3T multiparametric prostate magnetic resonance (MR) imaging and subsequent 3T IB-MRGB. The final study cohort included 379 men (with 475 targets) divided into 3 subcohorts: biopsy-naïve men (n = 123), individuals with a history of negative trans-rectal-ultrasonography (TRUS) biopsy results (n = 106), and men with low-grade PCa under active surveillance (n = 150). csPCa was defined as having a Gleason score (GS) ≥3+4. RESULTS: 3T IB-MRGB detected PCa and csPCa in 69.1% (262 of 379) and 50.3% (193 of 379) of patients, respectively. The PCa and csPCa detection rates per target were 64.2% (305 of 475) and 43.8% (208 of 475), respectively. The rate of urosepsis, treated with intravenous antibiotics, was 1% (4 patients). In TRUS biopsy negative results and biopsy-naïve subcohorts, csPCa was found in 36.8% (39 of 106) and 52.8% (65 of 123), respectively. In 50.7% (76 of 150) of the active surveillance subcohort, 3T IB-MRGB upgraded the GS assigned in prior TRUS biopsies. Positive predictive values of PIRADSv2.1 categories 3, 4, and 5 for csPCa detection were 24.8%, 44.4%, and 67.1%, respectively. Higher PIRADSv2.1 categories were significantly associated with PCa (odds ratio [OR], 3.97; 95% confidence interval [CI], 2.98-5.28) and csPCa (OR, 1.41; 95% CI, 1.03-1.94) detection. Of 137 PIRADSv2 category 3 lesions, 28 were downgraded to PIRADSv2.1 category 2, in which there were no occurrences of csPCa in histology. CONCLUSIONS: Use of 3T IB-MRGB resulted in detection of csPCa in 50.9% of individuals. 3T IB-MRGB has a high diagnostic yield in individuals with negative TRUS biopsy results and those under active surveillance. The PIRADSv2.1 category is a strong predictor of PCa and csPCa detection.

Three Tesla Multiparametric Magnetic Resonance Imaging: Comparison of Performance with and without Endorectal Coil for Prostate Cancer Detection, PI-RADS™ version 2 Category and Staging with Whole Mount Histopathology Correlation.

PURPOSE: We investigated the performance of 3 Tesla multiparametric magnetic resonance imaging with and without an endorectal coil to detect prostate cancer with a whole mount histopathology reference. MATERIALS AND METHODS: This retrospective HIPAA (Health Insurance Portability and Accountability Act) compliant, institutional review board approved, case-control study included patients who underwent 3 Tesla multiparametric magnetic resonance imaging with and without an endorectal coil from July 2009 to December 2016 prior to prostatectomy. The tumor detection rate was calculated for total and index lesions. Lesion magnetic resonance imaging and histopathology features were compared between the 2 groups. Using SPSS®, version 24 p <0.05 was considered significant. RESULTS: A total of 871 whole mount histopathology lesions in 429 patients with a mean ± SD age of 61.8 ± 7 years were included in analysis. The subcohorts with and without an endorectal coil comprised 260 and 169 patients with a total of 529 and 342 lesions, respectively. The overall tumor detection rates in all patients, and in the endorectal coil and nonendorectal coil subcohorts were 49.6% (432 of 871 patients), 50.5% (267 of 529) and 48.2% (165 of 342), respectively. The index tumor detection rates overall, and in the endorectal coil and nonendorectal coil subcohorts were 77.6% (333 of 429 patients), 78.5% (204 of 260) and 76.3% (129 of 169), respectively. In the endorectal coil and nonendorectal coil subcohorts we detected 35.9% (66 of 184) and 48.4% (76 of 157) of anterior lesions (p = 0.019), 58% (200 of 345) and 48.1% (89 of 185) of posterior lesions (p = 0.025), 37.3% (41 of 110) and 54.4% (62 of 114) of transition zone lesions (p = 0.010), and 53.7% (225 of 419) and 45.2% (103 of 228) of peripheral lesions (p = 0.033), respectively. After adjusting for clinical and pathological factors the endorectal coil group only showed higher detection of peripheral and posterior prostate cancer. CONCLUSIONS: We found that 3 Tesla multiparametric magnetic resonance imaging with and without an endorectal coil had similar detection of overall and index prostate cancer. However, the endorectal coil subcohort had significantly higher detection of posterior and peripheral prostate cancer, and lower detection of anterior and transition zone prostate cancer.

Characteristics of missed prostate cancer lesions on 3T multiparametric-MRI in 518 patients: based on PI-RADSv2 and using whole-mount histopathology reference.

PURPOSE: To determine the characteristics of missed prostate cancer (PCa) lesions on 3T multiparametric-MRI (mpMRI) based on PI-RADSv2 with whole-mount histopathology (WMHP) correlation. MATERIALS AND METHODS: This IRB-approved, HIPAA-compliant study, included 614 consecutive men with 3T mpMRI prior to prostatectomy at a single tertiary center between 12/2009 and 4/2017. Clinical, mpMRI, and pathologic features were obtained. PI-RADSv2-based MRI detected lesions were matched with previously finalized WMHP by a genitourinary (GU) radiologist and a GU pathologist. Patients with no mpMRI detected PCa lesion, but with at least one lesion ≥ 1 cm on WMHP, were reviewed retrospectively and assigned a PI-RADSv2 score. Tumor characteristics were compared between missed and detected lesions. RESULT: The final cohort included 518 patients with 1085 WMHP lesions. 51.9% (563/1085) of lesions were missed on 3T mpMRI. 71.4% (402/563), 21.7% (122/563), 4.4% (25/563), and 2.5% (14/563) of the missed lesions were Gleason scores (GS) 3 + 3, 3 + 4, 4 + 3, and 8 - 10, respectively. Missed PCa lesions had significantly lower proportion of GS ≥ 7 (p < 0.001) and smaller size for overall (p < 0.001) and index subcohorts (p < 0.001), as compared to detected lesions. 34.5% (194) of overall and 71.2% (79) index missed lesions were larger than 1 cm. In 13.7% (71/518) of patients without MR detected PCa, 149 lesions were detected on WMHP, with 70 (47%) lesions ≥ 1 cm. In retrospective review of these lesions, 42.9% (30), 18.6% (13), 21.5% (15), 10% (7), and 7% (5) were PI-RADSv2 1, 2, 3, 4, and 5, respectively. CONCLUSION: 3T mpMRI has an excellent per patients diagnostic performance for PCa and majority of missed lesions are clinically nonsignificant.