Preoperative prostate biopsy and multiparametric magnetic resonance imaging: reliability in detecting prostate cancer

Purpose

The aim of the study was to analyse and compare the ability of multiparametric magnetic resonance imaging (mp–MRI) and prostate biopsy (PB) to correctly identify tumor foci in patients undergoing radical prostatectomy (RP) for prostate cancer (PCa).

Materials and Methods

157 patients with clinically localised PCa with a PSA <10 ng/mL and a negative DRE diagnosed on the first (12 samples, Group A) or second (18 samples, Group B) PB were enrolled at our institution. All patients underwent mp-MRI with T2-weighted images, diffusion-weighted imaging, dynamic contrast enhanced-MRI prior to RP. A map of comparison describing each positive biopsy sample was created for each patient, with each tumor focus shown on the MRI and each lesion present on the definitive histological examination in order to compare tumor detection and location. The sensitivity of mp-MRI and PB for diagnosis was compared using Student’s t-test. The ability of the two exams to detect the prevalence of Gleason pattern 4 in the identified lesions was compared using a chi-square test.

Results

Overall sensitivity of PB and mp-MRI to identify tumor lesion was 59.4% and 78.9%, respectively (p<0.0001). PB missed 144/355 lesions, 59 of which (16.6%) were significant. mp-MRI missed 75/355 lesions, 12 of which (3.4%) were significant. No lesions with a GS≥8 were missed. Sensitivity of PB and mp-MRI to detect the prevalence of Gleason pattern 4 was 88.2% and 97.4%, respectively.

Conclusions

mp-MRI seems to identify more tumor lesions than PB and to provide more information concerning tumor characteristics.     

前列腺癌多参数磁共振成像影像组学研究进展

前列腺癌(prostate cancer,PCa)是最常见的男性泌尿系恶性肿瘤,近来我国前列腺癌的发病率呈明显上升的趋势[1]。多参数磁共振成像(multiparametric magnetic resonance imaging,mp-MRI)对前列腺癌病灶的检测和定位具有较高的敏感性[2]。尽管mp-MRI是一种强大的诊断工具,但是对mp-MRI图像序列的解读准确性仍有待提高[3],不同阅片者对良、恶性病变之间的界定存在高变异性,mp-MRI受到假阳性的限制,仅凭信号强度还不能准确预测和表征病理分级。近年来,许多研究将新兴的影像组学技术应用于mp-MRI诊断前列腺癌的研究中。本文就影像组学在前列腺癌mp-MRI中的研究现状及进展进行综述。     

Systematic biopsy should not be omitted in the era of combined magnetic resonance imaging/ultrasound fusion-guided biopsies of the prostate

Purpose

To evaluate prostate cancer detection rates with classical trans-rectal ultrasound-guided systematic 10-core biopsies (SB), targeted biopsies (TB) guided by magnetic resonance (MR)/US fusion imaging and their combination in biopsy-naïve and patients with previously negative prostate biopsies. We compared pathology results after radical prostatectomy with biopsy findings.

Methods

Consecutive patients with prostate imaging-reporting and data system lesions grade?≥?3 submitted to MRI/US-guided TB and subsequent standard 10-core SB between December 2015 and June 2019 were analyzed.

Results

Detection rate (TB- or SB-positive) in 563 included patients (192 naïve, 371 with previous biopsies) was 56.7% (67.7% for the first, 50.9% for repeated biopsies). With TB (disregarding SB), the rates were 41.4%, 52.1% and 35.8%, respectively. With SB (disregarding TB), the rates were 49.1%, 63.0% and 41.8%, respectively. Eventually, 118 patients underwent surgery and clinically significant cancer was found in 111 (94.1%) specimens. Of those, 23 (20.7%) would have been missed had we relied upon a negative TB and 14 (12.6%) would have been missed had we relied upon a negative SB, disregarding a positive finding on the alternative biopsy template.

Conclusion

SB should not be omitted since TB and SB combination have higher detection rate of clinically relevant prostate cancer than either procedure alone.

     

Accuracy of multiparametric magnetic resonance imaging in detecting recurrent prostate cancer after radiotherapy

OBJECTIVE

To assess the role of multiparametric magnetic resonance imaging (mp‐MRI) of the prostate in evaluating local recurrence of prostate cancer, using transperineal template‐guided 5 mm‐spaced biopsies as a reference standard, in men treated with external beam radiotherapy (EBRT) for prostate cancer.

PATIENTS AND METHODS

The study included 13 patients with evidence of biochemical recurrence after EBRT who had undergone mp‐MRI and prostate mapping. Each MRI scan (consisting of T1/T2 weighting, dynamic contrast enhancement and diffusion weighting) was reported by two expert uro‐radiologists. Each prostate was divided into four regions of interest (ROI), generating 52 paired datasets for analysis.

RESULTS

The mean (range) age of the men was 65.5 (55–70) years, the mean prostate‐specific antigen (PSA) level before EBRT was 36.6 (4.5–150) ng/mL, the mean time from EBRT to biochemical recurrence was 5.7 (3–10) years and the mean PSA level at the time of recurrence was 7.1 (0.83–27.9) ng/mL. Eleven men had histological evidence of recurrence, with 23 of 52 ROIs involved with cancer. Overall accuracy, as expressed by the area under a receiver‐operator curve, was 0.77 and 0.89 for all cancer, with accuracies of 0.86 and 0.93 for those cancers with ≥3 mm biopsy core length. Inter‐observer variability was measured by calculating κ coefficients, which showed fair and moderate agreement between radiologists.

CONCLUSIONS

Interpretation of mpMRI of the prostate after previous EBRT is challenging. Our results show that the accuracy is good using an accurate reference standard. These results need verification in more patients, but have implications for determining presence or absence of local recurrence and subsequent local salvage therapy.     

Prostate cancer management choices in patients undergoing multiparametric magnetic resonance imaging/ultrasound fusion biopsy compared to systematic biopsy

Objectives

To assess management choices in patients who undergo magnetic resonance imaging (MRI)/ultrasound (MRI/US) fusion-guided prostate biopsy compared to patients who undergo systematic biopsy.

Accuracy of preoperative multiparametric magnetic resonance imaging for prediction of unfavorable pathology in patients with localized prostate cancer undergoing radical prostatectomy

Introduction

We investigated the accuracy of multiparametric MRI (mpMRI) for preoperative staging and its influence on the determination of neurovascular bundle sparing and disease prognosis in patients with localized prostate cancer.

Methods

We reviewed 1045 patients who underwent radical prostatectomy with preoperative mpMRI at a single institution. Clinical local stages determined from mpMRI were correlated with preoperative and postoperative pathological outcomes.

Results

The sensitivity and specificity to diagnose seminal vesicle invasion (SVI) on mpMRI were 43.8 and 95.4 %, respectively. The negative predictive value was 78.9 %. The sensitivity and specificity to diagnose extracapsular extension (ECE) were 54.5 and 80.5 %, respectively. The overall sensitivity and specificity of diagnosing pathological T3 or higher were 52.6 and 82.1 %, respectively. Non-organ-confined disease determined by mpMRI was significantly associated with positive surgical margin and pathological T3 disease on multivariate analysis. Preoperative adverse findings on mpMRI were significantly associated with performance of the non-nerve-sparing technique.

Conclusion

mpMRI did not show outstanding diagnostic accuracy relative to our expectations in predicting SVI or ECE preoperatively. However, adverse findings on preoperative mpMRI were significantly related to worse postoperative pathological outcomes as well as postoperative biochemical recurrence.