Understanding tumor localization in multiparametric MRI of the prostate-effectiveness of 3D printed models

Introduction

Understanding tumor localization in multiparametric MRI (mpMRI) of the prostate is challenging for urologists but of great importance in mpMRI-fused prostate biopsy or radical prostatectomy. The aim was to evaluate the effectiveness of 3D printed models of the prostate to help urologists to locate tumors.

Methods and Participants

20 urologists from University Medical Center Mainz (Germany) were asked to plot the location of a cancer suspicious lesion (PI-RADS ≥ 4) on a total of 30 mpMRI on a prostate sector diagram. The following 3 groups (as matched triplets) were divided into: mpMRI only, mpMRI with radiological report and mpMRI with 3D printed model (scaled 1:1). Statistical analysis was performed using one-way and two-way ANOVA (with bonferroni post-test).

Results

Overall, localization of the suspicious lesion was superior with the radiological report (median of max. 10 [IQR]: MRI 2 [IQR 1;5], MRI + report: 8 [6.3;9], MRI + 3D model 3 [1.3;5.8]; p < 0.001). Residents with <1 year of experience had a significantly higher detection rate using a 3D printed model [5 (5;5.8)] compared to mpMRI alone [1.5 (1;3.5)] (p < 0.05). Regarding the estimation of index lesion extension, the 3D model showed a significant benefit (mean percentage difference [95% CI]: MRI alone 234% [17.1;451.5], MRI + report 114% [78.5;149.6], MRI + 3D model 17% [-7.4;41.3] (p < 0.01).

Conclusion

Urologists still need the written radiological report for a sufficient understanding of tumor localization. The effectiveness of the 3D printed model regarding tumor localization is particularly evident in young residents (<1 year) and leads to a better overall assessment of the tumor extension.

The association between prostate weight and positive surgical margins in prostate cancer: A meta-analysis

There have been some conflicting claims whether larger prostate weight (PW) reduces the risk of positive surgical margins (PSMs). This study aims to examine the associations between PW and PSMs. PubMed, Web of Science and Cochrane library were systematically retrieved. Relative risks (RRs) and the corresponding 95% confidence intervals (CIs) were synthesised utilising random-effect models. Ultimately, 22 cohort studies met criteria were enrolled in this meta-analysis, of which 18 studies reporting the RR of the highest VS lowest category of PW yielded the combined RR of PSMs of 0.61 (95% CI 0.50-0.74). Subgroup analysis showed that geographic region and surgical modalities were considered as potential confounders of influence of PW on PSMs. The nonlinear dose-response relationship demonstrated that PSM risk decreased by 1% (RR = 0.99, 95% CI, 0.98-0.99) for every one gram increment in PW. This study suggests PW has a negative association with risk of PSMs, and having a appropriate PW is very important.

[Prostate cancer diagnostic by saturation randomized biopsy versus rigid targeted biopsy]

INTRODUCTION

Optimal diagram teaming up randomized biopsy (BR) to targeted biopsy (BC) is still missing for the diagnostic of prostate cancer (CP). This study compares diagram of 6, 12 or 18 BR with or without BC rigid.

METHODS

Between January 2014 and May 2016, 120 patients had prostate biopsy BR and BC. Each patient had 18 BR and BC. Results compared sextant (6 BR), standard (12 BR) and saturation (18 BR) protocol with or without the adding of BC for the detection of CP.

RESULTS

Rectal examination was normal, mean PSA at 8.99ng/mL and mean volume at 54cm³. It was first round for 48% of patients. Forty-four cancers were found by the group 18 BR+BC (control). The detection rate was respectively, for 6, 12 and 18 BR of 61%, 82% and 91%. The add of BC increased this detection of +27% for 6 BR+BC, +13% for 12 BR+BC and +9% for 18 BR+BC. BC found 70% of all CP. Nine percent of CP were missed by BR only. Significant CP (Gleason≥7) diagnostic was the same for 12 BR+BC and 18 BR+BC.

CONCLUSION

The add of BC to BR increase the detection of CP by 10%. Twelve BR+BC is the optimal diagram for the diagnostic of CP finding 95% of CP and 97% of significant CP.

LEVEL OF EVIDENCE

4.

Low-Risk Prostate Cancer and Tumor Upgrading to Higher Patterns in the Surgical Specimen. Analysis of Clinical Factors Predicting Tumor Upgrading to Higher Gleason Patterns in a Contemporary Series of Patients Who Have Been Evaluated According to the Modified Gleason Score Grading System

OBJECTIVE

To identify clinical factors associated with prostate cancer (PCA) upgrading to higher patterns of the surgical specimen in low-risk PCA.

MATERIALS AND METHODS

We evaluated the records of 438 patients. The multinomial logistic regression model was used.

RESULTS

Low-risk PCA included 170 cases (38.8%) and tumor upgrading was detected in 111 patients (65.3%) of whom 72 (42.4%) had pathological Gleason patterns (pGP) = 3 + 4 and 39 (22.9%) pGP >3 + 4. Prostate-specific antigen (PSA) and proportion of positive cores (P+) were independent predictors of tumor upgrading to higher patterns. The main difference between upgraded cancers related to PSA and to P+ >0.20. The population was stratified into risk classes by PSA ≤5 μg/l and P+ ≤0.20 (class A), PSA >5 μg/l and P+ ≤0.20 (class B), PSA ≤5 μg/l and P+ >0.20 (class C) and PSA >5 μg/l and P+ 0.20 (class D). Upgrading rates to pGP >3 + 4 were extremely low in class A (5.1%), extremely high in D (53.8%).

CONCLUSIONS

Low-risk PCA is a heterogeneous population with significant rates of undetected high-grade disease. Significant clinical predictors of upgrading to higher patterns include PSA and P+, which identify a very high-risk class that needs repeat biopsies in order to reclassify tumor grade.