Prebiopsy Biparametric Magnetic Resonance Imaging Combined with Prostate-specific Antigen Density in Detecting and Ruling out Gleason 7–10 Prostate Cancer in Biopsy-naïve Men

Pahikkala

et al. 2019

Background: Accurate risk stratification of men with a clinical suspicion of prostate cancer (cSPCa) remains challenging despite the increasing use of MRI. Purpose: To evaluate the diagnostic accuracy of a unique biparametric MRI protocol (IMPROD bpMRI) combined with clinical and molecular markers in men with cSPCa. Study Type: Prospective single-institutional clinical trial (NCT01864135). Subjects: Eighty men with cSPCa. Field Strength/Sequence: 3T, surface array coils. Two T 2 -weighted and three diffusion-weighted imaging (DWI) acquisitions: 1) b-values 0, 100, 200, 300, 500 s/mm 2 ; 2) b-values 0,1500 s/mm 2 ; 3) b-values 0, 2000 s/mm 2 . Assessment: IMPROD bpMRI examinations were qualitatively (IMPROD bpMRI Likert score) and quantitatively (DWI-based Gleason grade score) prospectively reported. Men with IMPROD bpMRI Likert 3-5 had two targeted biopsies followed by 12-core systematic biopsies (SB); those with IMPROD bpMRI Likert 1-2 had only SB. Additionally, 2-core from normalappearing prostate areas were obtained for the mRNA expression of ACSM1, AMACR, CACNA1D, DLX1, PCA3, PLA2G7, RHOU, SPINK1, SPON2, TMPRSS2-ERG, and TDRD1 measured by quantitative reverse-transcription polymerase chain reaction. Statistical Tests: Univariate and multivariate analysis using regularized least-squares, feature selection and tournament leave-pair-out cross-validation (TLPOCV), as well as 10 random splits of the data in training-testing sets, were used to evaluate the mRNA, clinical and IMPROD bpMRI parameters in detecting clinically significant prostate cancer (SPCa) defined as Gleason score ≥ 3 + 4. The evaluation metric was the area under the curve (AUC). Results: IMPROD bpMRI Likert demonstrated the highest TLPOCV AUC of 0.92. The tested clinical variables had AUC 0.56-0.73, while the mRNA and additional IMPROD bpMRI parameters had AUC 0.50-0.67 and 0.65-0.89 respectively.View this article online at wileyonlinelibrary.com.

Section: Discussionmentioning

confidence: 90%

“…BpMRI without intravenous contrast agent has a key advantage of lower acquisition time (15 vs. up to 25–30 minutes), and thus, lower costs. Moreover, it is faster to perform due to time saved with patient preparation such as acquiring intravenous access . Adopting bpMRI with faster acquisitions might be more feasible on a larger scale.…”

Section: Discussionmentioning

confidence: 99%

Prostate Cancer Risk Stratification in Men With a Clinical Suspicion of Prostate Cancer Using a Unique Biparametric MRI and Expression of 11 Genes in Apparently Benign Tissue: Evaluation Using Machine‐Learning Techniques

Perez

Pahikkala

et al. 2019

“…Widespread use of prostate MRI in men with clinical suspicion of PCa can create a major financial burned on healthcare systems around the world. Thus, the use of a more rapid and cost‐effective prostate MRI protocol without the use intravenous contrast agent is desired …”

Section: Discussionmentioning

confidence: 99%

Qualitative and Quantitative Reporting of a Unique Biparametric MRI: Towards Biparametric MRI‐Based Nomograms for Prediction of Prostate Biopsy Outcome in Men With a Clinical Suspicion of Prostate Cancer (IMPROD and MULTI‐IMPROD Trials)

Perez

Kauko

et al. 2019

Background: Multiparametric MRI of the prostate has been shown to improve the risk stratification of men with an elevated prostate-specific antigen (PSA). However, long acquisition time, high cost, and inter-center/reader variability of a routine prostate multiparametric MRI limit its wider adoption. Purpose: To develop and validate nomograms based on unique rapid biparametric MRI (bpMRI) qualitative and quantitative derived variables for prediction of clinically significant cancer (SPCa). Study Type: Retrospective analyses of single (IMPROD, NCT01864135) and multiinstitution trials (MULTI-IMPROD, NCT02241122). Population: 161 and 338 prospectively enrolled men who completed the IMPROD and MULTI-IMPROD trials, respectively. Field Strength/Sequence: IMPROD bpMRI: 3T/1.5T, T 2 -weighted imaging, three separate diffusion-weighted imaging (DWI) acquisitions: 1) b-values 0, 100, 200, 300, 500 s/mm 2 ; 2) b values 0, 1500 s/mm 2 ; 3) values 0, 2000 s/mm 2 . Assessment: The primary endpoint of the combined trial analysis was the diagnostic accuracy of the combination of IMPROD bpMRI and clinical variables for detection of SPCa.View this article online at wileyonlinelibrary.com.

“…Following completion of the trial, all IMPROD bpMRI datasets were reported using the PI‐RADs v. 2 scoring system by the same reader . Specifically, the peripheral zone lesions were scored solely by DWI since dynamic contrast‐enhanced MRI was not performed . Suspicious lesions on IMPROD bpMRI were delineated manually on axial T 2 w images using integrated information from all bpMRI datasets without knowledge of clinical or laboratory parameters such as PSA level.…”

Section: Methodsmentioning

confidence: 99%

“…16 Specifically, the peripheral zone lesions were scored solely by DWI since dynamic contrast-enhanced MRI was not performed. 24,25 Suspicious lesions on IMPROD bpMRI were delineated manually on axial T 2 w images using integrated information from all bpMRI datasets without knowledge of clinical or laboratory parameters such as PSA level. The lesion extent was determined by the largest signal abnormality seen on T 2 w imaging or the separate three DWI acquisitions.…”

Section: Data Analysis and Interpretationmentioning

confidence: 99%

IMPROD biparametric MRI in men with a clinical suspicion of prostate cancer (IMPROD Trial): Sensitivity for prostate cancer detection in correlation with whole‐mount prostatectomy sections and implications for focal therapy

Merisaari

Ettala

et al. 2019

Background Prostate MRI is increasingly being used in men with a clinical suspicion of prostate cancer (PCa). However, development and validation of methods for focal therapy planning are still lagging. Purpose To evaluate the diagnostic accuracy on lesion, region‐of‐interest (ROI), and voxel level of IMPROD biparametric prostate MRI (bpMRI) for PCa detection in men with a clinical suspicion of PCa who subsequently underwent radical prostatectomy. Study Type Prospective single‐institution clinical trial (NCT01864135). Population Sixty‐four men who underwent radical prostatectomy after IMPROD bpMRI performed in prebiopsy settings. Field Strength/Sequence IMPROD bpMRI consisted of T2‐weighted imaging (T2w) and three separate diffusion‐weighted imaging acquisitions with an average acquisition time of 15 minutes. Assessment The diagnostic accuracy of prospectively reported manual cancer delineations and regions increased with 3D dilation were evaluated on the voxel level (volume of 1.17 mm3, 1 mm3, 125 mm3) as well as the 36 ROI level. Only PCa lesions with a diameter ≥ 5 mm or any Gleason Grade 4 were analyzed. All data and protocols are freely available at: http://petiv.utu.fi/improd Statistical Tests Sensitivity, specificity, accuracy. Results In total, 99 PCa lesions were identified. Forty (40%, 40/99) had a Gleason score (GS) of >3 + 4. Twenty‐eight PCa lesions (28%, 28/99) were missed by IMPROD bpMRI, three (7.5%, 3/40) with GS >3 + 4. 3D dilation of manual cancer delineations in all directions by ~10–12 mm (corresponding to the Hausdorff distance) was needed to achieve sensitivity approaching 100% on a voxel level. Data Conclusion IMPROD bpMRI had a high sensitivity on lesion level for PCa with GS >3 + 4. Increasing 3D lesion delineations by ~10–12 mm (corresponding to the Hausdorff distance) was needed to achieve high sensitivity on the voxel level. Such information may help in planning ablation therapies. Level of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1641–1650.