Use of multiparametric magnetic resonance imaging in prostate cancer active surveillance

Impact of genomic testing on urologists' treatment preference in favorable risk prostate cancer: A randomized trial

INTRODUCTION

The Oncotype Dx Genomic Prostate Score (GPS) is a 17-gene relative expression assay that predicts adverse pathology at prostatectomy. We conducted a novel randomized controlled trial to assess the impact of GPS on urologist's treatment preference for favorable risk prostate cancer (PCa): active surveillance versus active treatment (i.e., prostatectomy/radiation). This is a secondary endpoint from the ENACT trial which recruited from three Chicago hospitals from 2016 to 2019.

METHODS

Ten urologists along with men with very low to favorable-intermediate risk PCa were included in the study. Participants were randomly assigned to standardized counseling with or without GPS assay. The main outcome was urologists' preference for active treatment at Visit 2 by study arm (GPS versus Control). Multivariable best-fit binary logistic regressions were constructed to identify factors independently associated with urologists' treatment preference.

RESULTS

Two hundred men (70% Black) were randomly assigned to either the Control (96) or GPS arm (104). At Visit 2, urologists' preference for prostatectomy/radiation almost doubled in the GPS arm to 29.3% (29) compared to 14.1% (13) in the Control arm (p = 0.01). Randomization to the GPS arm, intermediate NCCN risk level, and lower patient health literacy were predictors for urologists' preference for active treatment.

DISCUSSION

Limitations included sample size and number of urologists. In this study, we found that GPS testing reduced urologists' likelihood to prefer active surveillance.

CONCLUSIONS

These findings demonstrate how obtaining prognostic biomarkers that predict negative outcomes before treatment decision-making might influence urologists' preference for recommending aggressive therapy in men eligible for active surveillance.

Abbreviated Versus Multiparametric Prostate MRI in Active Surveillance for Prostate-Cancer Patients: Comparison of Accuracy and Clinical Utility as a Decisional Tool

(1) Purpose: To compare the diagnostic accuracy between full multiparametric contrast-enhanced prostate MRI (mpMRI) and abbreviated dual-sequence prostate MRI (dsMRI) in men with clinically significant prostate cancer (csPCa) who were candidates for active surveillance. (2) Materials and Methods: Fifty-four patients with a diagnosis of low-risk PCa in the previous 6 months had a mpMRI scan prior to a saturation biopsy and a subsequent MRI cognitive transperineal targeted biopsy (for PI-RADS ≥ 3 lesions). The dsMRI images were obtained from the mpMRI protocol. The images were selected by a study coordinator and assigned to two readers blinded to the biopsy results (R1 and R2). Inter-reader agreement for clinically significant cancer was evaluated with Cohen's kappa. The dsMRI and mpMRI accuracy was calculated for each reader (R1 and R2). The clinical utility of the dsMRI and mpMRI was investigated with a decision-analysis model. (3) Results: The dsMRI sensitivity and specificity were 83.3%, 31.0%, 75.0%, and 23.8%, respectively, for R1 and R2. The mpMRI sensitivity and specificity were 91.7%, 31.0%, 83.3%, and 23.8%, respectively, for R1 and R2. The inter-reader agreement for the detection of csPCa was moderate (k = 0.53) and good (k = 0.63) for dsMRI and mpMRI, respectively. The AUC values for the dsMRI were 0.77 and 0.62 for the R1 and R2, respectively. The AUC values for the mpMRI were 0.79 and 0.66 for R1 and R2, respectively. No AUC differences were found between the two MRI protocols. At any risk threshold, the mpMRI showed a higher net benefit than the dsMRI for both R1 and R2. (4) Conclusions: The dsMRI and mpMRI showed similar diagnostic accuracy for csPCa in male candidates for active surveillance.

Are Urologists Ready for Interpretation of Multiparametric MRI Findings? A Prospective Multicentric Evaluation

Aim: To assess urologists’ proficiency in the interpretation of multiparametric magnetic resonance imaging (mpMRI). Materials and Methods: Twelve mpMRIs were shown to 73 urologists from seven Italian institutions. Responders were asked to identify the site of the suspicious nodule (SN) but not to assign a PIRADS score. We set an a priori cut-off of 75% correct identification of SN as a threshold for proficiency in mpMRI reading. Data were analyzed according to urologists’ hierarchy (UH; resident vs. consultant) and previous experience in fusion prostate biopsies (E-fPB, defined as <125 vs. ≥125). Additionally, we tested for differences between non-proficient vs. proficient mpMRI readers. Multivariable logistic regression analyses (MVLRA) tested potential predictors of proficiency in mpMRI reading. Results: The median (IQR) number of correct identifications was 8 (6−8). Anterior nodules (number 3, 4 and 6) represented the most likely prone to misinterpretation. Overall, 34 (47%) participants achieved the 75% cut-off. When comparing consultants vs. residents, we found no differences in terms of E-fPB (p = 0.9) or in correct identification rates (p = 0.6). We recorded higher identification rates in urologists with E-fBP vs. their no E-fBP counterparts (75% vs. 67%, p = 0.004). At MVLRA, only E- fPB reached the status of independent predictor of proficiency in mpMRI reading (OR: 3.4, 95% CI 1.2−9.9, p = 0.02) after adjusting for UH and type of institution. Conclusions: Despite urologists becoming more familiar with interpretation of mpMRI, their results are still far from proficient. E-fPB enhances the proficiency in mpMRI interpretation.

Association of prostate zonal volume with location and aggressiveness of clinically significant prostate cancer: A multiparametric MRI study according to PI-RADS version 2.1

BACKGROUND

The relationship between prostate cancer (PCa) and benign prostatic hyperplasia (BPH) remains unclear. This study aimed to determine whether prostate zonal volume was associated with the location and aggressiveness of PCa.

METHODS

412 PCa patients were retrospectively enrolled. The volumes of the whole prostate (V) and transition zone (Vtz) were calculated by the prolate ellipsoid formula, and volume of the peripheral zone (Vpz) was calculated by their subtraction. Locations of PCa were divided into three categories, including peripheral zone (PZ), transition zone (Vtz) and mixed zone group. The mixed zone group was further divided into PZ-dominated, TZ-dominated and equally distributed subgroups.

RESULTS

The Vtz of Gleason score (GS) 3 + 4 group was the largest, while the Vpz of GS 9 group was the largest. Tumor diameters of the PZ and TZ groups were weakly correlated with their corresponding zonal volume (r = 0.261, p < 0.001; r = 0.311, p = 0.009, respectively). There was no significant difference in the zonal volumes and GS distribution among the location groups. The proportion of tumors with high-grade GS of 8 and 9 was higher in the PZ than that in the TZ group (38.5 vs 24.3%, p = 0.041). For tumors located in the TZ, the V and Vpz of tumors with high-grade GS were larger than those in the low-grade GS of 7 group (p = 0.033 and 0.039, respectively). Among the subgroups of mixed zone group, the Vtz of the TZ-dominated group was larger than those of PZ-dominated and equally distributed groups (p = 0.016 and 0.001, respectively).

CONCLUSION

PCa with high-grade GS is more likely to have a relatively larger Vpz and involve PZ, while PCa with a larger Vtz is more likely to be with low-grade GS, which support the theoretical model that pressure exerted by increasing prostate size/mechanical deformation may inhibit PCa growth from the clinical point. However, the increase in zonal volume might not be the direct cause of tumorigenesis and aggressiveness.

The role of diagnostic ultrasound imaging for patients with known prostate cancer within an active surveillance pathway: A systematic review

BACKGROUND

The use of multiparametric magnetic resonance imaging (mpMRI) within active surveillance of prostate cancer programmes is identified by the UK National Institute for Health and Care Excellence (NICE guideline NG 131 2019) as having a role for monitoring disease. The widespread demands on mpMRI capacity may limit its use in surveillance. It is therefore timely to review the options that modern ultrasound imaging present to this cohort of patients in the monitoring of prostate cancer.

METHODS

Between April and September 2020, 10 databases were searched to recruit studies for the review. Three reviewers evaluated the publications for inclusion. Characteristics including the inclusion criteria for the study cohort, how disease was determined, identification of disease progression, and the modality and mode of imaging used were reviewed. Given the paucity of full text articles, a meta-analysis was not possible. A narrative review was undertaken.

RESULTS

In total, 12 studies, utilising the range of ultrasound parameters of B-mode, micro-ultrasound, colour Doppler, contrast ultrasound and elastography were included. The review demonstrated that micro-ultrasound offers promise as an imaging tool comparable with mpMRI. However, this is an emerging technology with limited availability. Analysis of the data further demonstrated that by combining the diagnostic features provided by multiple modes reviewed, ultrasound has a role in the diagnostic imaging of patients on active surveillance.

CONCLUSION

Providing a multiparametric approach is utilised, stable ultrasound findings may allow for increased intervals between biopsy for men on surveillance. The advent of micro-US offers promise as an imaging modality within an active surveillance pathway but requires further verification.

Cost-Effectiveness Analysis of Prostate Cancer Screening in Brazil

INTRODUCTION

Prostate cancer is one of the most common malignancies among men worldwide. Prostate-specific antigen (PSA) screening shows uncertain benefits and harms from clinical and economic perspectives, resulting in an important impact on healthcare systems. Because of nonstandardized studies and substantial differences among populations, data are still inconclusive.

OBJECTIVE

The objective of this study was to carry out long-term cost-effectiveness and cost-utility analysis on the PSA-screened population from the service provider's perspective in the Brazilian population.

METHODS

We performed a cost-effectiveness and cost-utility analysis using clinical outcomes obtained from 9692 men enrolled in the PSA screening program. Prostate cancer treatments, 5-year follow-up outcomes, and all related costs were examined. Data were compared with a nonscreened prostate cancer population to calculate incremental cost-effectiveness ratio (ICER) and incremental cost-utility ratio (ICUR). ICER and ICUR were compared with the Brazilian-established willingness-to-pay (WTP) threshold (WTP = R$ 114 026.55).

RESULTS

A total of 251 of 9692 men had a diagnosis of prostate cancer (2.6%), of which 90% had localized disease. Two hundred and five patients were treated as follows: surgery (45.37%); radiation therapy (11.22%); radiation plus androgen deprivation therapy (21.95%); active surveillance (13.17%); exclusive androgen deprivation therapy (7.32%); and watchful waiting (0.98%). Two simulated cohorts were compared based on screening and nonscreening groups. Values obtained were-ICER of R$ 44 491.39 per life saved and ICUR of R$ 10 851.56 per quality-adjusted life year (QALY) gained-below the Brazilian WTP threshold and showed cost-effectiveness and cost-utility advantages.

CONCLUSION

According to the Brazilian WTP, PSA screening is a cost-effective policy from a hospital and long-term perspective and should have more standardized studies developed in different populations and economies.

Multiparametric MRI in Active Surveillance of Prostate Cancer: An Overview and a Practical Approach

MRI has become important for the detection of prostate cancer. MRI-guided biopsy is superior to conventional systematic biopsy in patients suspected with prostate cancer. MRI is also increasingly used for monitoring patients with low-risk prostate cancer during active surveillance. It improves patient selection for active surveillance at diagnosis, although its role during follow-up is unclear. We aim to review existing evidence and propose a practical approach for incorporating MRI into active surveillance protocols.

A modified Delphi study to develop a practical guide for selecting patients with prostate cancer for active surveillance

Background

Active surveillance (AS) is a management option for men diagnosed with lower risk prostate cancer. There is wide variation in all aspects of AS internationally, from patient selection to investigations and follow-up intervals, and a lack of clear evidence on the optimal approach to AS. This study aimed to provide guidance for clinicians from an international panel of prostate cancer experts.

Methods

A modified Delphi approach was undertaken, utilising two rounds of online questionnaires followed by a face-to-face workshop. Participants indicated their level of agreement with statements relating to patient selection for AS via online questionnaires on a 7-point Likert scale. Factors not achieving agreement were iteratively developed between the two rounds of questionnaires. Draft statements were presented at the face-to-face workshop for discussion and consensus building.

Results

12 prostate cancer experts (9 urologists, 2 academics, 1 radiation oncologist) participated in this study from a range of geographical regions (4 USA, 4 Europe, 4 Australia). Complete agreement on statements presented to the participants was 29.4% after Round One and 69.0% after Round Two. Following robust discussions at the face-to-face workshop, agreement was reached on the remaining statements. PSA, PSA density, Multiparametric MRI, and systematic biopsy (with or without targeted biopsy) were identified as minimum diagnostic tests required upon which to select patients to recommend AS as a treatment option for prostate cancer. Patient factors and clinical parameters that identified patients appropriate to potentially receive AS were agreed. Genetic and genomic testing was not recommended for use in clinical decision-making regarding AS.

Conclusions

The lack of consistency in the practice of AS for men with lower risk prostate cancer between and within countries was reflected in this modified Delphi study. There are, however, areas of common practice and agreement from which clinicians practicing in the current environment can use to inform their clinical practice to achieve the best outcomes for patients.

Attitudes and perceptions towards multiparametric magnetic resonance imaging of the prostate: A national survey among Italian urologists

OBJECTIVE

We aimed to assess the attitudes and perceptions towards multiparametric magnetic resonance imaging (mpMRI) of the prostate among Italian urologists.

MATERIAL AND METHODS

A national, web-based survey was performed. A questionnaire composed of 18 multiple choice questions was e-mailed to 941 currently active urologists, members of the Italian Society of Urology. Preserving anonymity, respondents' demographics were collected (e.g. geographic region, type of workplace, prostate procedures performed) as well as data concerning their attitudes and perceptions towards mpMRI (e.g. indications deemed appropriate, degree of confidence in mpMRI results). Data were expressed as raw numbers and percentages of survey answers.

RESULTS

In total, 98 responses were received (participation rate = 10.4%). Respondents mostly worked in urban areas (96%) and primarily in hospital settings (89%), while 48% of them worked in southern Italy. 97% of respondents considered mpMRI useful to detect Prostate Cancer (PCa) in patients with prior negative biopsy, 64% in biopsy-naïve patients and 60% for PCa pre-operatory staging. About half (42%) of the participants declared that mpMRI results frequently lead them to change PCa management strategy. Standardization of mpMRI acquisition and reporting was partially unsatisfactory. Reported waiting time for mpMRI scans was longer than 4 weeks for 51% of respondents. The major limitation of this survey includes the small number of participants.

CONCLUSIONS

Prostate mpMRI is used by Italian urologists mainly for detection and for pre-operative staging of PCa. Further improvements in terms of mpMRI availability and report standardization are required.

Negative first follow-up prostate biopsy on active surveillance is associated with decreased risk of upgrading, suspicion of progression and converting to active treatment

OBJECTIVE

To determine the risk of disease progression and conversion to active treatment following a negative biopsy while on active surveillance (AS) for prostate cancer (PCa).

PATIENTS AND METHODS

Men on an AS programme at a single tertiary hospital (London, UK) between 2003 and 2018 with confirmed low-intermediate-risk PCa, Gleason Grade Group <3, clinical stage <T3 and a diagnostic prostate-specific antigen (PSA) level of <20 ng/mL. This cohort included men diagnosed by transrectal ultrasonography guided (12-14 cores) or transperineal (median 32 cores) biopsy. Multivariate Cox hazards regression analysis was undertaken to determine (i) risk of upgrading, (ii) clinical or radiological suspicion of disease progression, and (iii) transitioning to active treatment. Suspicion of disease progression was defined as any biopsy upgrading, >30% positive cores, magnetic resonance imaging (MRI) Likert score >3/T3 or PSA level of >20 ng/mL. Conversion to treatment included radical or hormonal treatment.

RESULTS

Among the 460 eligible patients, 23% had negative follow-up biopsy findings. The median follow-up was 62 months, with one to two repeat biopsies and two MRIs per patient during that period. Negative biopsy findings at first repeat biopsy were associated with decreased risk of converting to active treatment (hazard ration [HR] 0.18, 95% confidence interval [CI] 0.09-0.37; P < 0.001), suspicion of disease progression (HR 0.56, 95% CI: 0.34-0.94; P = 0.029), and upgrading (HR 0.48, 95% CI 0.23-0.99; P = 0.047). Data are limited by fewer men with multiple follow-up biopsies.

CONCLUSION

A negative biopsy finding at the first scheduled follow-up biopsy among men on AS for PCa was strongly associated with decreased risk of subsequent upgrading, clinical or radiological suspicion of disease progression, and conversion to active treatment. A less intense surveillance protocol should be considered for this cohort of patients.

Long-term outcomes of active surveillance for clinically localized prostate cancer in a community-based setting: results from a prospective non-interventional study

Purpose

To report on long-term outcomes of patients treated with active surveillance (AS) for localized prostate cancer (PCa) in the daily routine setting.

Methods

HAROW (2008–2013) was a non-interventional, health service research study about the management of localized PCa in the community setting, with 86% of the study centers being office-based urologists. A follow-up examination of all patients who opted for AS as primary treatment was carried out. Overall, cancer-specific, and metastasis-free survival, as well as discontinuation rates, were determined.

Results

Of 329 patients, 62.9% had very-low- and 21.3% low-risk tumours. The median follow-up was 7.7 years (IQR 4.7–9.1). Twenty-eight patients (8.5%) died unrelated to PCa, of whom 19 were under AS or watchful waiting (WW). Additionally, seven patients (2.1%) developed metastasis. The estimated 10-year overall and metastasis-free survival was 86% (95% CI 81.7–90.3) and 97% (95% CI 94.6–99.3), respectively. One hundred eighty-seven patients (56.8%) discontinued AS changing to invasive treatment: 104 radical prostatectomies (RP), 55 radiotherapies (RT), and 28 hormonal treatments (HT). Another 50 patients switched to WW. Finally, 37.4% remained alive without invasive therapy (22.2% AS and 15.2% WW). Intervention-free survival differed between the risk groups: 47.8% in the very-low-, 33.8% in the low- and 34.6% in the intermediate-/high-risk-group (p = 0.008). On multivariable analysis, PSA-density ≥ 0.2 ng/ml² was significantly predictive for receiving invasive treatment (HR 2.55; p = 0.001).

Conclusion

Even in routine care, AS can be considered a safe treatment option. Our results might encourage office-based urologists regarding the implementation of AS and to counteract possible concerns against this treatment option.

Electronic supplementary material

The online version of this article (10.1007/s00345-020-03471-x) contains supplementary material, which is available to authorized users.

The impact of complications after initial prostate biopsy on repeat protocol biopsy acceptance rate. Results from the Prostate Cancer Research International: Active Surveillance JAPAN study

BACKGROUND

Patients with favorable-risk prostate cancer on active surveillance (AS) are strictly followed for safer execution. Repeat protocol biopsy is essential for evaluating cancer aggressiveness. However, the acceptance rate of repeat biopsy is not high enough because of the burdens of biopsy. We assessed the impact of complications after the initial biopsy on repeat protocol biopsy at 1 year using data from the Prostate Cancer Research International: Active Surveillance (PRIAS)-JAPAN study.

METHODS

We performed a retrospective analysis using a prospective cohort in the PRIAS-JAPAN study. Patients with favorable-risk prostate cancer (n = 856) who consented to participate in the PRIAS-JAPAN study from 2010 to 2018 were enrolled. Follow-up evaluations included regular prostate-specific antigen, digital rectal examination and biopsy. Rates of complications after biopsies and repeat protocol biopsy non-acceptance rate at 1 year were reported. Logistic regression analysis explored the association between the complications after the initial biopsy and repeat protocol biopsy non-acceptance.

RESULTS

Altogether, 759 patients (88.7%) actually proceeded to protocol at 1 year. Repeat protocol biopsy non-acceptance rate at 1 year was 14.9%. Regarding complications after the initial biopsy, hematuria (p = 0.028) and pain (p < 0.001) rates were significantly higher in the repeat biopsy non-acceptance group, but infection (p = 0.056) and hematospermia (p = 0.337) rates were not different. On multivariate logistic regression analysis, pain was a significant predictor for repeat protocol biopsy non-acceptance (odds ratio 4.68, 95% confidence interval 1.864-11.75; p = 0.001).

CONCLUSIONS

Pain at the initial biopsy negatively impacts patients' compliance with further protocol biopsies during AS.