Interpreting Prostate MRI Reports in the Era of Increasing Prostate MRI Utilization: A Urologist's Perspective

Multi-parametric prostate MRI (mpMRI) is crucial for diagnosing, staging, and assessing treatment response in individuals with prostate cancer. Radiologists, through an accurate and standardized interpretation of mpMRI, stratify patients who may benefit from more invasive treatment or exclude patients who may be harmed by overtreatment. The integration of prostate MRI into the diagnostic pathway is anticipated to generate a substantial surge in the demand for high-quality mpMRI, estimated at approximately two million additional prostate MRI scans annually in Europe. In this review we examine the immediate impact on healthcare, particularly focusing on the workload and evolving roles of radiologists and urologists tasked with the interpretation of these reports and consequential decisions regarding prostate biopsies. We investigate important questions that influence how prostate MRI reports are handled. The discussion aims to provide insights into the collaboration needed for effective reporting.

The role of urology and radiology in prostate biopsy: current trends and future perspectives

PURPOSE

Prostate biopsy is central to the accurate histological diagnosis of prostate cancer. In current practice, the biopsy procedure can be performed using a transrectal or transperineal route with different technologies available for targeting of lesions within the prostate. Historically, the biopsy procedure was performed solely by urologists, but with the advent of image-guided techniques, the involvement of radiologists in prostate biopsy has become more common. Herein, we discuss the pros, cons and future considerations regarding their ongoing role.

METHODS

A narrative review regarding the current evidence was completed. PubMed and Cochrane central register of controlled trials were search until January 2024. All study types were of consideration if published after 2000 and an English language translation was available.

RESULTS

There are no published studies that directly compare outcomes of prostate biopsy when performed by a urologist or radiologist. In all published studies regarding the learning curve for prostate biopsy, the procedure was performed by urologists. These studies suggest that the learning curve for prostate biopsy is between 10 and 50 cases to reach proficiency in terms of prostate cancer detection and complications. It is recognised that many urologists are poorly able to accurately interpret multi parametric (mp)-MRI of the prostate. Collaboration between the specialities is of importance with urology offering the advantage of being involved in prior and future care of the patient while radiology has the advantage of being able to expertly interpret preprocedure MRI.

CONCLUSION

There is no evidence to suggest that prostate biopsy should be solely performed by a specific specialty. The most important factor remains knowledge of the relevant anatomy and sufficient volume of cases to develop and maintain skills.

Part I: prostate cancer detection, artificial intelligence for prostate cancer and how we measure diagnostic performance: a comprehensive review

MRI has firmly established itself as a mainstay for the detection, staging and surveillance of prostate cancer. Despite its success, prostate MRI continues to suffer from poor inter-reader variability and a low positive predictive value. The recent emergence of Artificial Intelligence (AI) to potentially improve diagnostic performance shows great potential. Understanding and interpreting the AI landscape as well as ever-increasing research literature, however, is difficult. This is in part due to widely varying study design and reporting techniques. This paper aims to address this need by first outlining the different types of AI used for the detection and diagnosis of prostate cancer, next deciphering how data collection methods, statistical analysis metrics (such as ROC and FROC analysis) and end points/outcomes (lesion detection vs. case diagnosis) affect the performance and limit the ability to compare between studies. Finally, this work explores the need for appropriately enriched investigational datasets and proper ground truth, and provides guidance on how to best conduct AI prostate MRI studies. Published in parallel, a clinical study applying this suggested study design was applied to review and report a multiple-reader multiple-case clinical study of 150 bi-parametric prostate MRI studies across nine readers, measuring physician performance both with and without the use of a recently FDA cleared Artificial Intelligence software.1.

Interpretation of Prostate Magnetic Resonance Imaging Using Prostate Imaging and Data Reporting System Version 2.1: A Primer

Prostate magnetic resonance imaging (MRI) is increasingly being used to diagnose and stage prostate cancer. The Prostate Imaging and Data Reporting System (PI-RADS) version 2.1 is a consensus-based reporting system that provides a standardized and reproducible method for interpreting prostate MRI. This primer provides an overview of the PI-RADS system, focusing on its current role in clinical interpretation. It discusses the appropriate use of PI-RADS and how it should be applied by radiologists in clinical practice to assign and report PI-RADS assessments. We also discuss the changes from prior versions and published validation studies on PI-RADS accuracy and reproducibility.

Use of Imaging and Biopsy in Prostate Cancer Diagnosis: A Survey From the Asian Prostate Imaging Working Group

OBJECTIVE

To elucidate the use of radiological studies, including nuclear medicine, and biopsy for the diagnosis and staging of prostate cancer (PCA) in clinical practice and understand the current status of PCA in Asian countries via an international survey.

MATERIALS AND METHODS

The Asian Prostate Imaging Working Group designed a survey questionnaire with four domains focused on prostate magnetic resonance imaging (MRI), other prostate imaging, prostate biopsy, and PCA backgrounds. The questionnaire was sent to 111 members of professional affiliations in Korea, Japan, Singapore, and Taiwan who were representatives of their working hospitals, and their responses were analyzed.

RESULTS

This survey had a response rate of 97.3% (108/111). The rates of using 3T scanners, antispasmodic agents, laxative drugs, and prostate imaging-reporting and data system reporting for prostate MRI were 21.6%-78.9%, 22.2%-84.2%, 2.3%-26.3%, and 59.5%-100%, respectively. Respondents reported using the highest b-values of 800-2000 sec/mm² and fields of view of 9-30 cm. The prostate MRI examinations per month ranged from 1 to 600, and they were most commonly indicated for biopsy-naïve patients suspected of PCA in Japan and Singapore and staging of proven PCA in Korea and Taiwan. The most commonly used radiotracers for prostate positron emission tomography are prostate-specific membrane antigen in Singapore and fluorodeoxyglucose in three other countries. The most common timing for prostate MRI was before biopsy (29.9%). Prostate-targeted biopsies were performed in 63.8% of hospitals, usually by MRI-ultrasound fusion approach. The most common presentation was localized PCA in all four countries, and it was usually treated with radical prostatectomy.

CONCLUSION

This survey showed the diverse technical details and the availability of imaging and biopsy in the evaluation of PCA. This suggests the need for an educational program for Asian radiologists to promote standardized evidence-based imaging approaches for the diagnosis and staging of PCA.

[Prostate Imaging Reporting and Data System (PI-RADS) v 2.1: Overview and Critical Points]

The technical parameters and imaging interpretation criteria of the Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) using multiparametric MRI (mpMRI) are updated in PI-RADS v2.1. These changes have been an expected improvement for prostate cancer evaluation, although some issues remain unsolved, and new issues have been raised. In this review, a brief overview of PI-RADS v2.1 is and several critical points are discussed as follows: the need for more detailed protocols of mpMRI, lack of validation of the revised transition zone interpretation criteria, the need for clarification for the revised diffusion-weighted imaging and dynamic contrast-enhanced imaging criteria, anterior fibromuscular stroma and central zone assessment, assessment of background signal and tumor aggressiveness, changes in the structured report, the need for the parameters for imaging quality and performance control, and indications for expansion of the system to include other indications.

Canadian Association of Radiologists Prostate MRI White Paper

Prostate cancer is the most common malignancy and the third most common cause of death in Canadian men. In light of evolving diagnostic pathways for prostate cancer and the increased use of MRI, which now includes its use in men prior to biopsy, the Canadian Association of Radiologists established a Prostate MRI Working Group to produce a white paper to provide recommendations on establishing and maintaining a Prostate MRI Programme in the context of the Canadian healthcare system. The recommendations, which are based on available scientific evidence and/or expert consensus, are intended to maintain quality in image acquisition, interpretation, reporting and targeted biopsy to ensure optimal patient care. The paper covers technique, reporting, quality assurance and targeted biopsy considerations and includes appendices detailing suggested reporting templates, quality assessment tools and sample image acquisition protocols relevant to the Canadian healthcare context.

Utility of a Rule-Based Algorithm in the Assessment of Standardized Reporting in PI-RADS

RATIONALE AND OBJECTIVES

Adoption of the Prostate Imaging Reporting & Data System (PI-RADS) has been shown to increase detection of clinically significant prostate cancer on prostate mpMRI. We propose that a rule-based algorithm based on Regular Expression (RegEx) matching can be used to automatically categorize prostate mpMRI reports into categories as a means by which to assess for opportunities for quality improvement.

MATERIALS AND METHODS

All prostate mpMRIs performed in the Duke University Health System from January 2, 2015, to January 29, 2021, were analyzed. Exclusion criteria were applied, for a total of 5343 male patients and 6264 prostate mpMRI reports. These reports were then analyzed by our RegEx algorithm to be categorized as PI-RADS 1 through PI-RADS 5, Recurrent Disease, or "No Information Available." A stratified, random sample of 502 mpMRI reports was reviewed by a blinded clinical team to assess performance of the RegEx algorithm.

RESULTS

Compared to manual review, the RegEx algorithm achieved overall accuracy of 92.6%, average precision of 88.8%, average recall of 85.6%, and F1 score of 0.871. The clinical team also reviewed 344 cases that were classified as "No Information Available," and found that in 150 instances, no numerical PI-RADS score for any lesion was included in the impression section of the mpMRI report.

CONCLUSION

Rule-based processing is an accurate method for the large-scale, automated extraction of PI-RADS scores from the text of radiology reports. These natural language processing approaches can be used for future initiatives in quality improvement in prostate mpMRI reporting with PI-RADS.

Structured reporting of CT scans of patients with trauma leads to faster, more detailed diagnoses: An experimental study

PURPOSE

This study aimed to determine whether structured reports (SRs) reduce reporting time and/or increase the level of detail for trauma CT scans compared to free-text reports (FTRs).

METHOD

Eight radiology residents used SRs and FTRs to describe 14 whole-body CT scans of patients with polytrauma in a simulated emergency room setting. Each resident created both a brief report and a detailed report for each case using one of the two formats. We measured the time to complete the detailed reports and established a scoring system to objectively measure report completeness and the level of detail. Scoring sheets divided the CT findings into main and secondary criteria. Finally, the radiological residents completed a questionnaire on their opinions of the SRs and FTRs.

RESULTS

The detailed SRs were completed significantly faster than the detailed FTRs (mean 19 min vs. 25 min; p < 0.001). The maximum allowance of 25 min was used for 25% of SRs and 59% of FTRs. For brief reports, the SRs contained more secondary criteria than the FTRs (p = 0.001), but no significant differences were detected in main criteria. Study participants rated their own SRs as significantly more time-efficient, concise, and clearly structured compared to the FTRs. However, SRs and FTRs were rated similarly for quality, accuracy, and completeness.

CONCLUSION

We found that SRs for whole-body trauma CT add clinical value compared to FTRs because SRs reduce reporting time and increase the level of detail for trauma CT scans.

Utilization of Coronary Artery Disease Reporting and Data System: A Survey of Cardiovascular Imaging Societies

OBJECTIVE

This survey was performed to determine the extent of utilization of Coronary Artery Disease Reporting and Data System (CAD-RADS) since its introduction in 2016 among members of cardiovascular imaging societies.

METHODS

A survey regarding use of CAD-RADS was distributed to members of North American Society for Cardiovascular Imaging and Society for Cardiovascular Computed Tomography.

RESULTS

A total of 246 surveys were completed, and results show that, although most respondents are familiar with CAD-RADS (95%), less than half (45%) report using CAD-RADS for all coronary CTA. Rates of CAD-RADS utilization were similar among physicians who work in a variety of settings. Years of clinical experience did not affect the rates of CAD-RADS utilization; however, a higher weekly volume of cardiac computed tomography was associated with higher rates of CAD-RADS utilization.

CONCLUSIONS

Four years after the introduction of CAD-RADS, the reporting system is used by less than half of surveyed members of North American Society for Cardiovascular Imaging and Society for Cardiovascular Computed Tomography regardless of practice model and range of practice experience with cardiac computed tomography.

State of the art in abdominal MRI structured reporting: a review

In the management of several abdominal disorders, magnetic resonance imaging (MRI) has the potential to significantly improve patient's outcome due to its diagnostic accuracy leading to more appropriate treatment choice. However, its clinical value heavily relies on the quality and quantity of diagnostic information that radiologists manage to convey through their reports. To solve issues such as ambiguity and lack of comprehensiveness that can occur with conventional narrative reports, the adoption of structured reporting has been proposed. Using a checklist and standardized lexicon, structured reports are designed to increase clarity while assuring that all key imaging findings related to a specific disorder are included. Unfortunately, structured reports have their limitations too, such as risk of undue report simplification and poor template plasticity. Their adoption is also far from widespread, and probably the ideal balance between radiologist autonomy and report consistency of has yet to be found. In this article, we aimed to provide an overview of structured reporting proposals for abdominal MRI and of works assessing its value in comparison to conventional free-text reporting. While for several abdominal disorders there are structured templates that have been endorsed by scientific societies and their adoption might be beneficial, stronger evidence confirming their imperativeness and added value in terms of clinical practice is needed, especially regarding the improvement of patient outcome.

Practice Patterns and Challenges of Performing and Interpreting Prostate MRI: A Survey by the Society of Abdominal Radiology Prostate Disease-Focused Panel

OBJECTIVE. The purpose of this study was to report on the practice patterns and challenges of performing and interpreting prostate MRI. SUBJECTS AND METHODS. An electronic survey regarding prostate MRI practice patterns and challenges was sent to members of the Society of Abdominal Radiology. RESULTS. The response rate was 15% (212/1446). Most (65%) of the respondents were academic abdominal radiologists with 1-5 (52%), 6-10 (20%), 11-20 (15%), and more than 20 (5%) years of experience in reporting prostate MRI. The numbers of prostate MRI examinations reported per week were 0-5 (43%), 6-10 (38%), 11-20 (12%), 21-30 (5%), and more than 30 (2%). Imaging was performed at 3 T (58%), 1.5 T (20%), or either (21%), and most examinations (83%) were performed without an endorectal coil. Highest b values ranged from 800 to 5000 s/mm²; 1400 s/mm² (26%) and 1500 s/mm² (30%) were the most common. Most respondents (79%) acquired dynamic contrast-enhanced images with temporal resolution of less than 10 seconds. Most (71%) of the prostate MRI studies were used for fusion biopsy. PI-RADS version 2 was used by 92% of the respondents and template reporting by 80%. Challenges to performing and interpreting prostate MRI were scored on a 1-5 Likert scale (1, easy; 2, somewhat easy; 3, neutral; 4, somewhat difficult; 5, very difficult). The median scores were 2 or 3 for patient preparatory factors. Image acquisition and reporting factors were scored 1-2, except for performing spectroscopy or using an endorectal coil, both of which scored 4. Acquiring patient history scored 2 and quality factors scored 3. CONCLUSION. Most radiologists perform prostate MRI at 3 T without an endorectal coil and interpret the images using PI-RADS version 2. Challenges include obtaining quality images, acquiring feedback, and variability in the interpretation of PI-RADS scores.

Discrepant Reporting Style Preferences Between Clinicians and Radiologists

RATIONALE AND OBJECTIVES

To compare preferences in reporting styles between radiologists and clinicians in structured vs unstructured reporting styles in order to facilitate better communication.

METHODS

An online survey was distributed to 5280 clinicians, radiologists, and physicians in training surveying respondent preference for three different reporting styles: expanded structured, minimized structured, and unstructured.

RESULTS

A 7.5% response rate was achieved. Overall, the expanded structured reporting style was the most preferred (47%, 186/394). This contrasted with radiologists who preferred the unstructured reporting style (41%), whereas nonradiologists preferred the expanded structured reporting style (51%; P < 0.001). There was significance in emergency medicine physicians preferring the minimized structured reporting style (51%, 27/43), whereas all other specialties preferred the expanded structured report (49%, 168/341; P = 0.0038).

DISCUSSION

There is a discrepant reporting style preference between clinicians and radiologists. A structured reporting style with expanded standard statements is preferred by most physicians. Radiologists could consider using a structured reporting style with minimized normal statements in the emergency room setting.

Perspective: a critical assessment of PI-RADS 2.1

PURPOSE

In this article we take a critical look at the key changes of the newest edition of the Prostate Imaging Reporting and Data System (PI-RADS) version 2.1 (v2.1) and indicate future directions for further development of the system.

CONCLUSION

PI-RADS v2.1 addresses some of the shortcomings of its widely embraced precursor version 2, largely to simplify interpretation and improve interobserver agreement without changing the fundamental acquisition and scoring guidelines. Biparametric MRI is acknowledged in the newest version, but multiparametric MRI including dynamic contrast-enhanced imaging is still recommended for most scenarios. Management recommendations and guidance on evaluation of follow-up MRI's are still not included in the system.

Structured prostate MRI reporting: how and why

Over the past decade, the Prostate Imaging-Reporting and Data System (PI-RADS) has revolutionized the manner in which prostate cancer is screened for, detected, biopsied, and managed. The single greatest contribution of PI-RADS has been the standardization of interpretation and reporting of findings on MRI of the prostate. This standardization has led to the wide acceptance of the PI-RADS lexicon at a time when structured reporting templates are becoming more widespread in radiology and other medical fields. The author reviews the benefits of structured reporting templates with a focus on prostate MRI, prior studies on this topic, and details of a suggested template.

Comparison of PI-RADS version 2.1 and PI-RADS version 2 regarding interreader variability and diagnostic accuracy for transition zone prostate cancer

PURPOSE

To compare the diagnostic performance of PI-RADS version 2.1 (PI-RADS v2.1) and PI-RADS v2 for transition zone prostate cancer (TZPC), and analyse its performance for readers with different experience levels.

METHODS

Eighty-five patients with suspected prostate cancer who underwent biopsy after MRI scan between January and December 2017 were retrospectively enrolled. One junior radiologist (reader 1, 1 year of experience in using PI-RADS v2) and one senior radiologist (reader 2, 6 years of experience) independently reviewed and assigned a score for each lesion according to PI-RADS v2.1 and v2. The template-guided transperineal prostate biopsy was used for standard of reference. To compare the diagnostic performance of the two methods, the AUC was calculated. The sensitivity, specificity, and accuracy were calculated at predefined positive values (PI-RADS ≥ 3). The interreader agreement and frequency of prostate cancer for each PI-RADS category were also calculated.

RESULTS

Among the 85 patients, 27 had prostate cancers, and 25 were clinically significant prostate cancer (csPCa). The AUC values for diagnosing clinically significant prostate cancer significantly increased with PI-RADS v2.1 for reader 2 (0.766 vs. 0.902, P = 0.009). The specificity and accuracy for both readers also increased with PI-RADS v2.1 (specificity: reader 1, 41.7% vs. 78.3% and reader 2, 33.3% vs. 81.7%; accuracy: reader 1, 52.9% vs. 76.5% and reader 2, 48.2% vs. 83.5%, all P < 0.05). The interreader agreement was good for both versions. The percentage of prostate cancer decreased in lower PI-RADS categories (PI-RADS 2) and increased in higher PI-RADS categories (PI-RADS 3 ~ 4).

CONCLUSION

Compared with PI-RADS v2, PI-RADS v2.1 may improve radiologists' diagnostic performance for TZPC.

PI-RADS Version 2.1: A Critical Review, From the AJR Special Series on Radiology Reporting and Data Systems

PI-RADS version 2.1 updates the technical parameters for multiparametric MRI (mpMRI) of the prostate and revises the imaging interpretation criteria while maintaining the framework introduced in version 2. These changes have been considered an improvement, although some issues remain unresolved, and new issues have emerged. Areas for improvement discussed in this review include the need for more detailed mpMRI protocols with optimization for 1.5-T and 3-T systems; lack of validation of revised transition zone interpretation criteria and need for clarifications of the revised DWI and dynamic contrast-enhanced imaging criteria and central zone (CZ) assessment; the need for systematic evaluation and reporting of background changes in signal intensity in the prostate that can negatively affect cancer detection; creation of a new category for lesions that do not fit into the PI-RADS assessment categories (i.e., PI-RADS M category); inclusion of quantitative parameters beyond size to evaluate lesion aggressiveness; adjustments to the structured report template, including standardized assessment of the risk of extraprostatic extension; development of parameters for image quality and performance control; and suggestions for expansion of the system to other indications (e.g., active surveillance and recurrence).

Comparison of Urologist Satisfaction for Different Types of Prostate MRI Reports: A Large Sample Investigation

Objective

To evaluate urologist satisfaction on structured prostate MRI reports, including report with tumor-node-metastasis (TNM) staging (report B) and with Prostate Imaging Reporting and Data System (PI-RADS) score with/without TNM staging (report C, report with PI-RADS score only [report C-a] and report with PI-RADS score and TNM staging [C-b]) compared with conventional free-text report (report A).

Materials and Methods

This was a prospective comparative study. Altogether, 3015 prostate MRI reports including reports A, B, C-a, and C-b were rated by 13 urologists using a 5-point Likert Scale. A questionnaire was used to assess urologist satisfaction based on the following parameters: correctness, practicality, and urologist subjectivity. Kruskal-Wallis H-test followed by Nemenyi test was used to compare urologists' satisfaction parameters for each report type. The rate of urologist-radiologist recalls for each report type was calculated.

Results

Reports B and C including its subtypes had higher ratings of satisfaction than report A for overall satisfaction degree, and parameters of correctness, practicality, and subjectivity (p < 0.05). There was a significant difference between report B and C (p < 0.05) in practicality score, but no statistical difference was found in overall satisfaction degree, and correctness and subjectivity scores (p > 0.05). Compared with report C-b (p > 0.05), report B and C-a (p < 0.05) showed a significant difference in overall satisfaction degree and parameters of practicality and subjectivity. In terms of correctness score, neither report C-a nor C-b had a significant difference with report B (p > 0.05). No statistical difference was found between report C-a and C-b in overall satisfaction degree and all three parameters (p > 0.05). The rate of urologist-radiologist recalls for reports A, B, C-a and C-b were 29.1%, 10.8%, 18.1% and 11.2%, respectively.

Conclusion

Structured reports, either using TNM or PI-RADS are highly preferred over conventional free-text reports and lead to fewer report-related post-hoc inquiries from urologists.

Current Role of Multiparametric MRI and MRI Targeted Biopsies for Prostate Cancer Diagnosis in Germany: A Nationwide Survey

INTRODUCTION

Multiparametric MRI (mpMRI) and MRI targeted biopsies (MRtb) are a new standard in prostate cancer (PCa) screening and diagnosis. Guidelines already include this approach for patients at risk. We aimed to gather information from German urologists about their knowledge, routine use, and attitude toward mpMRI and consecutive biopsy methods.

MATERIALS AND METHODS

An anonymous online questionnaire was sent via Survey Monkey to the members of the German Society of Urology (DGU). Statistical analyses were performed using SPSS version 25.0.

RESULTS

496 members with a median age of 48.6 years (±11.7) participated in the survey. The majority rated mpMRI of the prostate as a very useful diagnostic tool (72.7%). MRtb of the prostate was considered as very advantageous (71.5%). MpMRI was used by 95.9%, and 83.2% also recommended MRtb predominantly in clinical institutions. For targeted biopsy, MRI-ultrasound fusion biopsy was clearly favored (75.8%). MpMRI was mostly used in patients with previously negative biopsy (90.9%) and in patients under active surveillance (60.9%). Arguments against the use of prostate mpMRI are costs (84.9%) and/or lack of sufficient radiological infrastructure (17.4%).

CONCLUSION

Our data illustrate the meanwhile high acceptance and clinical use of the prostate mpMRI and MRtb in Germany.

Feasibility of integrating computer-aided diagnosis with structured reports of prostate multiparametric MRI

OBJECTIVES

To evaluate the feasibility of integrating computer-aided diagnosis (CAD) with structured reports of prostate multiparametric MRI (mpMRI).

METHODS

This retrospective study enrolled 153 patients who underwent prostate mpMRI for the purpose of targeted biopsy; patients were divided into a group with clinically significant prostate cancer (csPCa, Gleason score ≥ 3 + 4, n = 89) and a group with non-csPCa (n = 64). Ten inexperienced radiologists retrospectively evaluated these cases (single reader per case) twice using structured reports, and they were blinded to the pathologic results. Initially, the readers interpreted mpMRI without CAD. Six weeks later, they evaluated the same cases again with CAD assistance. At each time of image interpretation, lesions detected by the readers were marked on the prostate vector map in structured reports, and a PI-RADS score was given to each lesion. Diagnostic efficacy and reading time were evaluated for the two reading sessions.

RESULTS

With the assistance of CAD, the overall diagnostic efficacy was improved, i.e., the AUC increased from 0.83 to 0.89 (p = 0.018). Specifically, per-patient sensitivity (84.3% vs. 93.3%) and per-lesion sensitivity (76.7% vs. 88.8%) were significantly improved (all p < 0.05). Per-patient specificity with CAD (65.6%) was higher than that without CAD (56.3%), but statistical significance was not reached (p = 0.238). The reading time for each case decreased from 10.9 min to 7.8 min (p < 0.001).

CONCLUSIONS

It is feasible to integrate CAD with structured reports of prostate mpMRI. This reading paradigm can improve the diagnostic sensitivity of csPCa detection and reduce reading time among inexperienced radiologists.

Prostate Imaging Reporting and Data System Version 2 for MRI of Prostate Cancer: Can We Do Better?

OBJECTIVE. Although the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) has been widely adopted and is generally considered a success, it has clear limitations. The purpose of this article is to highlight the strengths and weaknesses of PI-RADSv2 and discuss ways that it can be improved. CONCLUSION. PI-RADSv2 has improved standardization of acquisition and interpretation of prostate MR images. Although it improves the detection of clinically significant cancers, its subjectivity and intrareader variability limit its accuracy and reproducibility, causing concerns regarding its reliability.

Structured reporting of prostate magnetic resonance imaging has the potential to improve interdisciplinary communication

BACKGROUND

Effective interdisciplinary communication of imaging findings is vital for patient care, as referring physicians depend on the contained information for the decision-making and subsequent treatment. Traditional radiology reports contain non-structured free text and potentially tangled information in narrative language, which can hamper the information transfer and diminish the clarity of the report. Therefore, this study investigates whether newly developed structured reports (SRs) of prostate magnetic resonance imaging (MRI) can improve interdisciplinary communication, as compared to non-structured reports (NSRs).

METHODS

50 NSRs and 50 SRs describing a single prostatic lesion were presented to four urologists with expert level experience in prostate cancer surgery or targeted MRI TRUS fusion biopsy. They were subsequently asked to plot the tumor location in a 2-dimensional prostate diagram and to answer a questionnaire focusing on information on clinically relevant key features as well as the perceived structure of the report. A validated scoring system that distinguishes between "major" and "minor" mistakes was used to evaluate the accuracy of the plotting of the tumor position in the prostate diagram.

RESULTS

The mean total score for accuracy for SRs was significantly higher than for NSRs (28.46 [range 13.33-30.0] vs. 21.75 [range 0.0-30.0], p < 0.01). The overall rates of major mistakes (54% vs. 10%) and minor mistakes (74% vs. 22%) were significantly higher (p < 0.01) for NSRs than for SRs. The rate of radiologist re-consultations was significantly lower (p < 0.01) for SRs than for NSRs (19% vs. 85%). Furthermore, SRs were rated as significantly superior to NSRs in regard to determining the clinical tumor stage (p < 0.01), the quality of the summary (4.4 vs. 2.5; p < 0.01), and overall satisfaction with the report (4.5 vs. 2.3; p < 0.01), and as more valuable for further clinical decision-making and surgical planning (p < 0.01).

CONCLUSIONS

Structured reporting of prostate MRI has the potential to improve interdisciplinary communication. Through SRs, expert urologists were able to more accurately assess the exact location of single prostate cancer lesions, which can facilitate surgical planning. Furthermore, structured reporting of prostate MRI leads to a higher satisfaction level of the referring physician.

Assessment of PI-RADS v2 categories ≥ 3 for diagnosis of clinically significant prostate cancer

PURPOSE

To assess the diagnostic accuracy of PI-RADS v2 categories ≥ 3 to detect clinically significant prostate cancer (csPCa) against histopathology of Transperineal Mapping Biopsy (TPMB).

MATERIALS AND METHODS

IRB-approved retrospective cohort study included 47 men who had 3.0 T multi-parametric MRI (mpMRI) and TPMB of prostate. Two radiologists independently evaluated T2, DWI, ADC map, and DCE images using PI-RADS v2 categories. A third radiologist served as tie-breaker. PI-RADS v2 score (PS) ≥ 3 lesions were correlated with 3D model of TPMB (3DTPMB) results based on prostate sectors. Two groups of csPCa status were separately analyzed for accuracy measures at lesion and person levels: Group 1 with GS (Gleason Score) ≥ 7 and group 2 with tumor volume ≥ 0.5 cc. Inter-rater reliability for PS and MR lexicon was calculated.

RESULTS

Forty-seven patients with 3DTPMB had at least one lesion with PS ≥ 3 on mpMRI. PS of 5 had high PPV and high specificity of 100% at the lesion and person levels. Sensitivity of a PS ≥ 3 was 68.27% for group 1 and was 48.39% for group 2. Specificity was 93.56% for group 1 and was 95.53% for group 2. At the person level, sensitivity of PS ≥ 3 was 81.25% for group 1 and was 82.35% for group 2. Specificity was 32.26% for group 1 and was 53.85% for group 2.

CONCLUSION

PI-RADS v2 category of 5 had high PPV and specificity; however, combined PS ≥ 3 had mixed performance in detection of csPCa.

Prostate Magnetic Resonance Imaging: Lesion Detection and Local Staging

Dramatic changes in the use of prostate magnetic resonance imaging (MRI) have occurred in the last decade. The recognition that MRI detects and localizes cancers with reasonable accuracy led to the development of directed biopsies. These image-guided biopsies have a higher sensitivity for clinically significant cancers and a lower sensitivity for indolent disease. Prospective trials provide level 1 evidence supporting the use of prostate MRI. For local staging, while the specificity of prostate MRI is high, its sensitivity is lacking for microscopic extraprostatic extension. Computer-aided diagnosis of prostate MRI promises to bring the diagnostic power of MRI to nonexpert readers and thus further integrate MRI into the diagnostic workup.

Radiologists' preferences regarding content of prostate MRI reports: a survey of the Society of Abdominal Radiology

PURPOSE

To evaluate radiologist preferences regarding specific content that warrants inclusion in prostate MRI reports.

METHODS

Sixty-one members of the Society of Abdominal Radiology responded to a 74-item survey regarding specific content warranted in prostate MRI reports, conducted in August 2016.

RESULTS

General items deemed essential report content by ≥ 50% of respondents were prostate volume (80%), extent of prostate hemorrhage (74%), TURP defects (69%), coil type (64%), BPH (61%), contrast dose (61%), contrast agent (59%), medications administered (59%), and magnet strength (54%). Details regarding lesion description deemed essential by ≥ 50% were overall PI-RADS category (88%), DCE (±) (82%), subjective degree of diffusion restriction (72%), T2WI intensity (72%), T2WI margins (65%), T2WI shape (52%), DWI 1-5 score (50%), and T2WI 1-5 score (50%). Details deemed essential to include in the report Impression by ≥ 50% of respondents were lymphadenopathy and metastases (100%), EPE (98%), SVI (98%), neurovascular bundle involvement (93%), index lesion location (93%), PI-RADS category of index lesion (82%), number of suspicious lesions (78%), significance of index lesion PI-RADS category (53%), and PI-RADS category of non-index lesions (52%). Preferred methods for lesion localization were slice/image number (68%), 3-part craniocaudal level (68%), zonal location (65%), anterior vs. posterior location (57%), and medial vs. lateral position (56%). Least preferred methods for localization were numeric sector from the PI-RADS sector map (8%), annotated screen capture (10%), and graphical schematic of PI-RADS sector map (11%).

CONCLUSION

Radiologists generally deemed a high level of detail warranted in prostate MRI reports. The PI-RADS v2 sector map was disliked for lesion localization.

Prostate Imaging-Reporting and Data System Steering Committee: PI-RADS v2 Status Update and Future Directions

CONTEXT

The Prostate Imaging-Reporting and Data System (PI-RADS) v2 analysis system for multiparametric magnetic resonance imaging (mpMRI) detection of prostate cancer (PCa) is based on PI-RADS v1, accumulated scientific evidence, and expert consensus opinion.

OBJECTIVE

To summarize the accuracy, strengths and weaknesses of PI-RADS v2, discuss pathway implications of its use and outline opportunities for improvements and future developments.

EVIDENCE ACQUISITION

For this consensus expert opinion from the PI-RADS steering committee, clinical studies, systematic reviews, and professional guidelines for mpMRI PCa detection were evaluated. We focused on the performance characteristics of PI-RADS v2, comparing data to systems based on clinicoradiologic Likert scales and non-PI-RADS v2 imaging only. Evidence selections were based on high-quality, prospective, histologically verified data, with minimal patient selection and verifications biases.

EVIDENCE SYNTHESIS

It has been shown that the test performance of PI-RADS v2 in research and clinical practice retains higher accuracy over systematic transrectal ultrasound (TRUS) biopsies for PCa diagnosis. PI-RADS v2 fails to detect all cancers but does detect the majority of tumors capable of causing patient harm, which should not be missed. Test performance depends on the definition and prevalence of clinically significant disease. Good performance can be attained in practice when the quality of the diagnostic process can be assured, together with joint working of robustly trained radiologists and urologists, conducting biopsy procedures within multidisciplinary teams.

CONCLUSIONS

It has been shown that the test performance of PI-RADS v2 in research and clinical practice is improved, retaining higher accuracy over systematic TRUS biopsies for PCa diagnosis.

PATIENT SUMMARY

Multiparametric magnetic resonance imaging (MRI) and MRI-directed biopsies using the Prostate Imaging-Reporting and Data System improves the detection of prostate cancers likely to cause harm, and at the same time decreases the detection of disease that does not lead to harms if left untreated. The keys to success are high-quality imaging, reporting, and biopsies by radiologists and urologists working together in multidisciplinary teams.