The Impact of Omitting Contralateral Systematic Biopsy on the Surgical Planning of Patients with a Unilateral Suspicious Lesion on Magnetic Resonance Imaging Undergoing Robot-assisted Radical Prostatectomy for Prostate Cancer

Background and objective

A combined approach of magnetic resonance imaging (MRI)-targeted biopsy (TBx) and bilateral systematic biopsy (SBx) is advised in patients who have an increased risk of prostate cancer (PCa). The diagnostic gain of SBx in detecting PCa for treatment planning of patients undergoing robot-assisted radical prostatectomy (RARP) is unknown. This study aims to determine the impact of omitting contralateral SBx on the surgical planning of patients undergoing RARP in terms of nerve-sparing surgery (NSS) and extended pelvic lymph node dissection (ePLND).

Methods

Case files from 80 men with biopsy-proven PCa were studied. All men had a unilateral suspicious lesion on MRI, and underwent TBx and bilateral SBx. Case files were presented to five urologists for the surgical planning of RARP. Each case file was presented randomly using two different sets of information: (1) results of TBx + bilateral SBx, and (2) results of TBx + ipsilateral SBx. The urologists assessed whether they would perform NSS and/or ePLND.

Key findings and limitations

A change in the surgical plan concerning NSS on the contralateral side was observed in 9.0% (95% confidence interval [CI] 6.4-12.2) of cases. Additionally, the indication for ePLND changed in 5.3% (95% CI 3.3-7.9) of cases. Interobserver agreement based on Fleiss' kappa changed from 0.44 to 0.15 for the indication of NSS and from 0.84 to 0.83 for the indication of ePLND.

Conclusions and clinical implications

In our series, the diagnostic information obtained from contralateral SBx has limited impact on the surgical planning of patients with a unilateral suspicious lesion on MRI scheduled to undergo RARP.

Patient summary

In patients with one-sided prostate cancer on magnetic resonance imaging, omitting biopsies on the other side rarely changed the surgical plan with respect to nerve-sparing surgery and the indication to perform extended lymph node dissection.

The accuracy and intra- and interobserver variability of PSMA PET/CT for the local staging of primary prostate cancer

PURPOSE

Prostate-specific membrane antigen (PSMA) positron emission tomography/ computed tomography (PET/CT) is recognized as the most accurate imaging modality for detection of metastatic high-risk prostate cancer (PCa). Its role in the local staging of disease is yet unclear. We assessed the intra- and interobserver variability, as well as the diagnostic accuracy of the PSMA PET/CT based molecular imaging local tumour stage (miT-stage) for the local tumour stage assessment in a large, multicentre cohort of patients with intermediate and high-risk primary PCa, with the radical prostatectomy specimen (pT-stage) serving as the reference standard.

METHODS

A total of 600 patients who underwent staging PSMA PET/CT before robot-assisted radical prostatectomy was studied. In 579 PSMA positive primary prostate tumours a comparison was made between miT-stage as assessed by four nuclear physicians and the pT-stage according to ISUP protocol. Sensitivity, specificity and diagnostic accuracy were determined. In a representative subset of 100 patients, the intra-and interobserver variability were assessed using Kappa-estimates.

RESULTS

The sensitivity and specificity of the PSMA PET/CT based miT-stage were 58% and 59% for pT3a-stage, 30% and 97% for ≥ pT3b-stage, and 68% and 61% for overall ≥ pT3-stage, respectively. No statistically significant differences in diagnostic accuracy were found between tracers. We found a substantial intra-observer agreement for PSMA PET/CT assessment of ≥ T3-stage (k 0.70) and ≥ T3b-stage (k 0.75), whereas the interobserver agreement for the assessment of ≥ T3-stage (k 0.47) and ≥ T3b-stage (k 0.41) were moderate.

CONCLUSION

In a large, multicentre study evaluating 600 patients with newly diagnosed intermediate and high-risk PCa, we showed that PSMA PET/CT may have a value in local tumour staging when pathological tumour stage in the radical prostatectomy specimen was used as the reference standard. The intra-observer and interobserver variability of assessment of tumour extent on PSMA PET/CT was moderate to substantial.

A Systematic Review on the Diagnostic Value of Fibroblast Activation Protein Inhibitor PET/CT in Genitourinary Cancers

In contemporary oncologic diagnostics, molecular imaging modalities are pivotal for precise local and metastatic staging. Recent studies identified fibroblast activation protein as a promising target for molecular imaging across various malignancies. Therefore, we aimed to systematically evaluate the current literature on the utility of fibroblast activation protein inhibitor (FAPI) PET/CT for staging patients with genitourinary malignancies. Methods: A systematic Embase and Medline search was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) process, on August 1, 2023. Relevant publications reporting on the diagnostic value of FAPI PET/CT in genitourinary malignancies were identified and included. Studies were critically reviewed using a modified version of a tool for quality appraisal of case reports. Study results were summarized using a narrative approach. Results: We included 22 retrospective studies with a cumulative total of 69 patients, focusing on prostate cancer, urothelial carcinoma of the bladder and of the upper urinary tract, renal cell carcinoma, and testicular cancer. FAPI PET/CT was able to visualize both local and metastatic disease, including challenging cases such as prostate-specific membrane antigen (PSMA)-negative prostate cancer. Compared with radiolabeled 18F-FDG and PSMA PET/CT, FAPI PET/CT showed heterogeneous performance. In selected cases, FAPI PET/CT demonstrated superior tumor visualization (i.e., better tumor-to-background ratios and visualization of small tumors or metastatic deposits visible in no other way) over 18F-FDG PET/CT in detecting local or metastatic disease, whereas comparisons with PSMA PET/CT showed both superior and inferior performances. Challenges in FAPI PET/CT arise from physiologic urinary excretion of most FAPI radiotracers, hindering primary-lesion visualization in the bladder and upper urinary tract, despite generally providing high tumor-to-background ratios. Conclusion: The current findings suggest that FAPI PET/CT may hold promise as a future tool to aid clinicians in detecting genitourinary malignancies. Given the substantial heterogeneity among the included studies and the limited number of patients, caution in interpreting these findings is warranted. Subsequent prospective and comparative investigations are anticipated to delve more deeply into this innovative imaging modality and elucidate its role in clinical practice.

A Systematic Review on the Impact of Quality Assurance Programs on Outcomes after Radical Prostatectomy

BACKGROUND AND OBJECTIVE

The implementation of quality assurance programs (QAPs) within urological practice has gained prominence; yet, their impact on outcomes after radical prostatectomy (RP) remains uncertain. This paper aims to systematically review the current literature regarding the implementation of QAPs and their impact on outcomes after robot-assisted RP, laparoscopic RP, and open prostatectomy, collectively referred to as RP.

METHODS

A systematic Embase, Medline (OvidSP), and Scopus search was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) process, on January 12, 2024. Studies were identified and included if these covered implementation of QAPs and their impact on outcomes after RP. QAPs were defined as any intervention seeking quality improvement through critically reviewing, analyzing, and discussing outcomes. Included studies were assessed critically using the Risk of Bias in Nonrandomized Studies of Interventions (ROBINS-I) tool, with results summarized narratively.

KEY FINDINGS AND LIMITATIONS

Ten included studies revealed two methodological strategies: periodic performance feedback and surgical video assessments. Despite conceptual variability, QAPs improved outcomes consistently (ie, surgical margins, urine continence, erectile function, and hospital readmissions). Of the two strategies, video assessments better identified suboptimal surgical practice and technical errors. Although the extent of quality improvements did not appear to correlate with the frequency of QAPs, there was an apparent correlation with whether or not outcomes were evaluated collectively.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Current findings suggest that QAPs have a positive impact on outcomes after RP. Caution in interpretation due to limited data is advised. More extensive research is required to explore how conceptual differences impact the extent of quality improvements.

PATIENT SUMMARY

In this paper, we review the available scientific literature regarding the implementation of quality assurance programs and their impact on outcomes after radical prostatectomy. The included studies offered substantial support for the implementation of quality assurance programs as an incentive to improve the quality of care continuously.

Development and Internal Validation of a Novel Nomogram Predicting the Outcome of Salvage Radiation Therapy for Biochemical Recurrence after Radical Prostatectomy in Patients without Metastases on Restaging Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography

Background and objective

Owing to the greater use of prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in patients with biochemical recurrence (BCR) of prostate cancer (PCa) after robot-assisted radical prostatectomy (RARP), patient selection for local salvage radiation therapy (sRT) has changed. Our objective was to determine the short-term efficacy of sRT in patients with BCR after RARP, and to develop a novel nomogram predicting BCR-free survival after sRT in a nationwide contemporary cohort of patients who underwent PSMA PET/CT before sRT for BCR of PCa, without evidence of metastatic disease.

Methods

All 302 eligible patients undergoing PCa sRT in four reference centers between September 2015 and August 2020 were included. We conducted multivariable logistic regression analysis using a backward elimination procedure to develop a nomogram for predicting biochemical progression of PCa, defined as prostate-specific antigen (PSA) ≥0.2 ng/ml above the post-sRT nadir within 1 yr after sRT.

Key findings and limitations

Biochemical progression of disease within 1 yr after sRT was observed for 56/302 (19%) of the study patients. The final predictive model included PSA at sRT initiation, pathological grade group, surgical margin status, PSA doubling time, presence of local recurrence on PSMA PET/CT, and the presence of biochemical persistence (first PSA result ≥0.1 ng/ml) after RARP. The area under the receiver operating characteristic curve for this model was 0.72 (95% confidence interval 0.64-0.79). Using our nomogram, patients with a predicted risk of >20% had a 30.8% chance of developing biochemical progression within 1 yr after sRT.

Conclusions

Our novel nomogram may facilitate better patient counseling regarding early oncological outcome after sRT. Patients with high risk of biochemical progression may be candidates for more extensive treatment.

Patient summary

We developed a new tool for predicting cancer control outcomes of radiotherapy for patients with recurrence of prostate cancer after surgical removal of their prostate. This tool may help in better counseling of these patients with recurrent cancer regarding their early expected outcome after radiotherapy.

The Probability of Metastases Within Different Prostate-specific Antigen Ranges Using Prostate-specific Membrane Antigen Positron Emission Tomography in Patients with Newly Diagnosed Prostate Cancer

Background and objectives

The association between prostate-specific antigen (PSA) level and probability of metastatic disease on prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) has not yet been established in patients with newly diagnosed prostate cancer (PCa). Our objective was to assess the probability of metastatic disease within different PSA ranges using PSMA PET/CT for initial staging of PCa, and to identify both the anatomical distribution and the predictors of metastases on PSMA PET/CT.

Methods

In total, 2193 patients with newly diagnosed PCa were retrospectively studied. PSMA PET/CT was performed for staging purposes between January 2017 and May 2022. The proportion of patients with PSMA-avid metastases, stratified by PSA level, was studied. A vast majority of patients in whom at least one high-risk prognostic factor was present underwent PSMA PET/CT. A multivariable logistic regression analysis was performed to identify the predictors of metastases on PSMA PET/CT using clinical, biochemical, radiological, and pathological variables.

Key findings and limitations

The median PSA level at PSMA PET/CT was 14.1 ng/ml. Any metastatic disease (miN1-M1a-c) was observed in 34.7% (763/2193) of all patients and distant metastases (miM1a-c) in 25.4% (557/2193) of patients. The presence of any metastatic disease increased with PSA levels, being 15.4% in men with PSA levels <10 ng/ml and 87.5% in men with PSA levels >100 ng/ml. The multivariable logistic regression analysis found significant associations between the presence of any metastatic disease and PSA subgroups, clinical tumor stage ≥T2, grade group >3, and radiological tumor stage ≥T3b.

Conclusions and clinical implications

This is the first large epidemiological study in patients with PCa demonstrating the association between PSA subgroups and metastatic disease on modern imaging PSMA PET/CT. Data from this study can be used to counsel patients on the probability of metastatic disease at the time of PSA screening and to provide guidance on existing guidelines.

Patient summary

The prostate-specific antigen level could be used to assess the risk of metastases on prostate-specific membrane antigen positron (PSMA) emission tomography/computed tomography (PET/CT). This knowledge is valuable for selecting patients who will benefit most from metastatic screening with PSMA PET/CT.

Development and External Validation of a Novel Nomogram to Predict the Probability of Pelvic Lymph-node Metastases in Prostate Cancer Patients Using Magnetic Resonance Imaging and Molecular Imaging with Prostate-specific Membrane Antigen Positron Emission Tomography

BACKGROUND

Preoperative assessment of the probability of pelvic lymph-node metastatic disease (pN1) is required to identify patients with prostate cancer (PCa) who are candidates for extended pelvic lymph-node dissection (ePLND).

OBJECTIVE

To develop a novel intuitive prognostic nomogram for predicting pathological lymph-node (pN) status in contemporary patients with primary diagnosed localized PCa, using preoperative clinical and histopathological parameters, magnetic resonance imaging (MRI), and prostate-specific membrane antigen (PSMA) positron emission tomography (PET).

DESIGN, SETTING, AND PARTICIPANTS

In total, 700 eligible patients who underwent robot-assisted radical prostatectomy and ePLND were included in the model-building cohort. The external validation cohort consisted of 305 surgically treated patients. Logistic regression with backward elimination was used to select variables for the Amsterdam-Brisbane-Sydney nomogram.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Performance of the final model was evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision-curve analyses. Models were subsequently validated in an external population.

RESULTS AND LIMITATIONS

The Amsterdam-Brisbane-Sydney nomogram included initial prostate-specific antigen value, MRI T stage, highest biopsy grade group (GG), biopsy technique, percentage of systematic cores with clinically significant PCa (GG ≥2), and lymph-node status on PSMA-PET. The AUC for predicting pN status was 0.81 (95% confidence interval [CI] 0.78-0.85) for the final model. On external validation, the Amsterdam-Brisbane-Sydney nomogram showed superior discriminative ability to the Briganti-2017 and Memorial Sloan Kettering Cancer Center (MSKCC) nomograms (AUC 0.75 [95% CI 0.69-0.81] vs 0.67 [95% CI 0.61-0.74] and 0.65 [95% CI 0.58-0.72], respectively; p < 0.05), and similar discriminative ability to the Briganti-2019 nomogram (AUC 0.78 [95% CI 0.71-0.86] vs 0.80 [95% CI 0.73-0.86]; p = 0.76). The Amsterdam-Brisbane-Sydney nomogram showed excellent calibration on external validation, with an increased net benefit at a threshold probability of ≥4%.

CONCLUSIONS

The validated Amsterdam-Brisbane-Sydney nomogram performs superior to the Briganti-2017 and MSKCC nomograms, and similar to the Briganti-2019 nomogram. Furthermore, it is applicable in all patients with newly diagnosed unfavorable intermediate- and high-risk PCa.

PATIENT SUMMARY

We developed and validated the Amsterdam-Brisbane-Sydney nomogram for the prediction of prostate cancer spread to lymph nodes before surgery. This nomogram performs similar or superior to all presently available nomograms.

Using prostate-specific membrane antigen positron-emission tomography to guide prostate biopsies and stage men at high-risk of prostate cancer

OBJECTIVE

To assess whether a diagnostic pathway in which prostate-specific membrane antigen (PSMA) positron-emission tomography (PET)/computed tomography (CT) is used as a single imaging modality is feasible to guide targeted biopsy and to detect clinically significant prostate cancer (csPCa) in biopsy-naïve men at high-risk of disease.

PATIENTS AND METHODS

A total of 60 men with a prostate-specific antigen (PSA) level of 20-50 ng/mL underwent 18 F-PSMA(DCFPyL)-PET/CT prior to prostate biopsies in this prospective, non-randomised cohort study. Magnetic resonance imaging (MRI) was not performed. Using a 12-segment mapping model of the prostate, PSMA-guided targeted biopsy was performed along with systematic biopsies. The detection rate of PCa and csPCa was assessed for combined systematic and targeted biopsy, and for targeted biopsy only. csPCa was defined as a prostate biopsy with an International Society of Uropathology (ISUP) Grade Group ≥2.

RESULTS

Lesions suspicious for PCa in the prostate gland were observed on all PSMA-PET/CTs. A total of 27/60 men (45%) already had metastatic disease on staging 18 F-PSMA(DCFPyL)-PET/CT. Combined PSMA-guided targeted and systematic biopsies detected PCa in 56/60 (93.3%) patients, with 52 of them (92.9%) having csPCa. PSMA-guided targeted biopsy, if performed as a single biopsy modality, identified PCa in 52/60 men (86.7%) and in 27/27 men (100%) men with metastases.

CONCLUSIONS

Using the PSMA-driven single imaging modality pathway in biopsy-naïve men at high-risk of PCa, a substantial number of diagnostic MRI scans could be avoided while at the same time obtaining adequate targeting, staging, and detection of csPCa.

Optimization and validation of 18F-DCFPyL PET radiomics-based machine learning models in intermediate- to high-risk primary prostate cancer

INTRODUCTION

Radiomics extracted from prostate-specific membrane antigen (PSMA)-PET modeled with machine learning (ML) may be used for prediction of disease risk. However, validation of previously proposed approaches is lacking. We aimed to optimize and validate ML models based on 18F-DCFPyL-PET radiomics for the prediction of lymph-node involvement (LNI), extracapsular extension (ECE), and postoperative Gleason score (GS) in primary prostate cancer (PCa) patients.

METHODS

Patients with intermediate- to high-risk PCa who underwent 18F-DCFPyL-PET/CT before radical prostatectomy with pelvic lymph-node dissection were evaluated. The training dataset included 72 patients, the internal validation dataset 24 patients, and the external validation dataset 27 patients. PSMA-avid intra-prostatic lesions were delineated semi-automatically on PET and 480 radiomics features were extracted. Conventional PET-metrics were derived for comparative analysis. Segmentation, preprocessing, and ML methods were optimized in repeated 5-fold cross-validation (CV) on the training dataset. The trained models were tested on the combined validation dataset. Combat harmonization was applied to external radiomics data. Model performance was assessed using the receiver-operating-characteristics curve (AUC).

RESULTS

The CV-AUCs in the training dataset were 0.88, 0.79 and 0.84 for LNI, ECE, and GS, respectively. In the combined validation dataset, the ML models could significantly predict GS with an AUC of 0.78 (p<0.05). However, validation AUCs for LNI and ECE prediction were not significant (0.57 and 0.63, respectively). Conventional PET metrics-based models had comparable AUCs for LNI (0.59, p>0.05) and ECE (0.66, p>0.05), but a lower AUC for GS (0.73, p<0.05). In general, Combat harmonization improved external validation AUCs (-0.03 to +0.18).

CONCLUSION

In internal and external validation, 18F-DCFPyL-PET radiomics-based ML models predicted high postoperative GS but not LNI or ECE in intermediate- to high-risk PCa. Therefore, the clinical benefit seems to be limited. These results underline the need for external and/or multicenter validation of PET radiomics-based ML model analyses to assess their generalizability.

Staging fluorodeoxyglucose positron emission tomography/computed tomography for muscle-invasive bladder cancer: a nationwide population-based study

OBJECTIVE

To provide insight into the use and staging information on lymph-node involvement added by fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with muscle-invasive bladder cancer (MIBC), based on a nationwide population-based cohort study.

PATIENTS AND METHODS

We analysed a nationwide cohort of patients with MIBC without signs of distant metastases, newly diagnosed in the Netherlands between November 2017 and October 2019. From this cohort, we selected patients who underwent pre-treatment staging with CT only or CT and FDG-PET/CT. The distribution of patients, disease characteristics, imaging findings, nodal status (clinical nodal stage cN0 vs cN+) and treatment were described for each imaging modality group (CT only vs CT and FDG-PET/CT).

RESULTS

We identified 2731 patients with MIBC: 1888 (69.1%) underwent CT only; 606 (22.2%) underwent CT and FDG-PET/CT, 237 (8.6%) underwent no CT. Of the patients who underwent CT only, 200/1888 (10.6%) were staged as cN+, vs 217/606 (35.8%) who underwent CT and FDG-PET/CT. Stratified analysis showed that this difference was found in patients with clinical tumour stage (cT)2 as well as cT3/4 MIBC. Of patients who underwent both imaging modalities and were staged with CT as cN0, 109/498 (21.9%) were upstaged to cN+ based on FDG-PET/CT. Radical cystectomy (RC) was the most common treatment within both imaging groups. Preoperative chemotherapy was more frequently applied in cN+ disease and in FDG-PET/CT-staged patients. Concordance of pathological N stage after upfront RC was higher among patients staged as cN+ with CT and FDG-PET/CT (50.0% pN+) than those staged as cN+ with only CT (39.3%).

CONCLUSION

Patients with MIBC who underwent pre-treatment staging with FDG-PET/CT were more often staged as lymph node positive, regardless of cT stage. In patients with MIBC who underwent CT and FDG-PET/CT, FDG-PET/CT led to clinical nodal upstaging in approximately one-fifth. Additional imaging findings may influence subsequent treatment strategies.

Histopathological concordance between prostate biopsies and radical prostatectomy specimens-implications of transrectal and transperineal biopsy approaches

BACKGROUND

This study aimed to evaluate the histopathological concordance rates between prostate biopsies and radical prostatectomy specimens according to the applied biopsy approach (transrectal or transperineal).

METHODS

We studied patients who had been newly diagnosed with clinically significant prostate cancer and who underwent a radical prostatectomy between 2018 and 2022. Patients were included if they underwent a prebiopsy magnetic resonance imaging and if they had not been previously treated for prostate cancer. Histopathological grading on prostate biopsies was compared with that on radical prostatectomy specimens. Univariable and multivariable logistic regression analyses were performed to assess the effect of the applied biopsy approach on histopathological concordance. Additional analyses were performed to assess the effect of the applied biopsy approach on American Urological Association risk group migration, defined as any change in risk group after radical prostatectomy.

RESULTS

In total, 1058 men were studied, of whom 49.3% (522/1058) and 50.7% (536/1058) underwent transrectal and transperineal prostate biopsies, respectively. Histopathological disconcordance was observed in 37.8% (400/1058) of men while American Urological Association risk group migration was observed in 30.2% (320/1058) of men. A transperineal biopsy approach was found to be independently associated with higher histopathological concordance rates (OR 1.33 [95% CI 1.01-1.75], p = 0.04) and less American Urological Association risk group migration (OR 0.70 [95% CI 0.52-0.93], p = 0.01).

CONCLUSIONS

The use of a transperineal biopsy approach improved histopathological concordance rates compared to the use of a transrectal biopsy approach. A transperineal biopsy approach may provide more accurate risk stratification for clinical decision-making. Despite recent improvements, histopathologic concordance remains suboptimal and should be considered before initiating management.

TripleAiM1: a nationwide registry of de novo metastatic hormone-sensitive prostate cancer with prospective quality-of-life assessment

INTRODUCTION

The treatment landscape for de novo metastatic hormone sensitive prostate cancer (mHSPC) is rapidly evolving. With an abundance of available treatment strategies, selecting the optimal strategy for an individual patient is becoming increasingly challenging. TripleAiM1 aims to evaluate the impact of mHSPC treatments on health-related quality of life (HRQoL) and to provide real-world data insights on diagnostics, treatment strategies, patient subgroups and related healthcare expenditure for mHSPC. The aspirational target of TripleAiM1 is that in the near future, a more tailored therapy can be offered based on the individual patient's wishes and needs in accordance with the overarching principle of value-based healthcare.

METHODS AND ANALYSIS

We describe the TripleAiM1 study design; a nationwide registry comprising a retrospective and prospective cohort of patients with de novo mHSPC. Starting in May 2020, eligible patients are identified, selected and recruited in 14 participating hospitals in the Netherlands. Our hypothesis is that, in a real-world setting, differences in clinically meaningful HRQoL deterioration will be observed for treatment strategies over time. HRQoL data, assessed with patient-reported outcome measures, costs and clinical data will be collected for 24 months.For the retrospective cohort, all patients diagnosed with de novo mHSPC from January 2017 onwards are eligible for inclusion. Patient and tumour characteristics, imaging modalities and treatment patterns will be analysed descriptively to provide a real-world overview.Time-to-event endpoints will be assessed using the Kaplan-Meier method and regression models will be employed to analyse baseline characteristics associated with an increased likelihood of death, progression and HRQoL deterioration. Longitudinal mixed-effects models will be employed to assess change of patient-reported outcome scores from baseline until the end of follow-up.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Medical Research Ethics Committee, Twente. Study results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NL9719.

Higher Preoperative Maximum Standardised Uptake Values (SUVmax) Are Associated with Higher Biochemical Recurrence Rates after Robot-Assisted Radical Prostatectomy for [68Ga]Ga-PSMA-11 and [18F]DCFPyL Positron Emission Tomography/Computed Tomography

This study aimed to investigate the association between the 68Ga- or 18F-radiolabeled prostate-specific membrane antigen (PSMA) tracer expression, represented by the maximum standardised uptake value (SUVmax) of the dominant intraprostatic lesion, and biochemical recurrence (BCR) in primary prostate cancer (PCa) patients prior to robot-assisted radical prostatectomy (RARP). This was a retrospective, multi-centre cohort study of 446 patients who underwent [68Ga]Ga-PSMA-11 (n = 238) or [18F]DCFPyL (n = 206) Positron Emission Tomography/Computed Tomography (PET/CT) imaging prior to RARP. SUVmax was measured in the dominant intraprostatic PCa lesions. [18F]DCFPyL patients were scanned 60 ([18F]DCFPyL-60; n = 106) or 120 ([18F]DCFPyL-120; n = 120) minutes post-injection of a radiotracer and were analysed separately. To normalise the data, SUVmax was log transformed for further analyses. During a median follow-up of 24 months, 141 (30.4%) patients experienced BCR. Log2SUVmax was a significant predictor for BCR (p < 0.001). In the multivariable analysis accounting for these preoperative variables: initial prostate-specific antigen (PSA), radiologic tumour stage (mT), the biopsy International Society of Urological Pathology grade group (bISUP) and the prostate imaging and reporting data system (PI-RADS), Log2SUVmax was found to be an independent predictor for BCR in [68Ga]Ga-PSMA-11 (HR 1.32, p = 0.04) and [18F]DCFPyL-120 PET/CT scans (HR 1.55, p = 0.04), but not in [18F]DCFPyL-60 ones (HR 0.92, p = 0.72). The PSMA expression of the dominant intraprostatic lesion proved to be an independent predictor for BCR in patients with primary PCa who underwent [68Ga]Ga-PSMA-11 or [18F]DCFPyL-120 PET/CT scans, but not in those who underwent [18F]DCFPyL-60 PET/CT scans.

The Diagnostic Value of PSMA PET/CT in Men with Newly Diagnosed Unfavorable Intermediate-Risk Prostate Cancer

Our objective was to determine the diagnostic value of prostate-specific membrane antigen (PSMA) PET/CT in staging men with newly diagnosed unfavorable intermediate-risk prostate cancer (PCa). Methods: Patients with newly diagnosed unfavorable intermediate-risk PCa, in whom PSMA PET/CT was performed as a primary staging modality, were retrospectively studied. PSMA PET/CT was performed at several diagnostic centers and reported by expert nuclear medicine physicians within 2 high-volume PCa centers. A multivariate logistic regression analysis, taking into account clinical, biochemical, pathologic, and radiologic variables, was performed to identify potential independent predictors for metastatic disease on PSMA PET/CT. Results: In total, 396 men with newly diagnosed unfavorable intermediate-risk PCa were studied. Metastatic disease was observed in 37 (9.3%) men, of whom 29 (7.3%) had molecular imaging locoregional lymph node metastases (miN1) and 16 (4.0%) had distant metastases (miM1). A radiologic tumor stage of at least T3 on MRI (odds ratio, 2.72 [95% CI, 1.27-5.83]; P = 0.01) and more than 50% positive prostate biopsies (odds ratio, 3.87 [95% CI, 1.74-8.62]; P = 0.001) were found to be independently associated with metastatic disease on PSMA PET/CT. Conclusion: Given that metastatic disease was observed in nearly 1 in 10 men with newly diagnosed unfavorable intermediate-risk PCa, PSMA PET/CT is considered to be of diagnostic value within this population. Further stratification using the radiologic tumor stage and the percentage of positive prostate biopsies could aid in identifying those patients at risk of having metastatic disease on PSMA PET/CT.

Treating Primary Node-Positive Prostate Cancer: A Scoping Review of Available Treatment Options

There is currently no consensus on the optimal treatment for patients with a primary diagnosis of clinically and pathologically node-positive (cN1M0 and pN1M0) hormone-sensitive prostate cancer (PCa). The treatment paradigm has shifted as research has shown that these patients could benefit from intensified treatment and are potentially curable. This scoping review provides an overview of available treatments for men with primary-diagnosed cN1M0 and pN1M0 PCa. A search was conducted on Medline for studies published between 2002 and 2022 that reported on treatment and outcomes among patients with cN1M0 and pN1M0 PCa. In total, twenty-seven eligible articles were included in this analysis: six randomised controlled trials, one systematic review, and twenty retrospective/observational studies. For cN1M0 PCa patients, the best-established treatment option is a combination of androgen deprivation therapy (ADT) and external beam radiotherapy (EBRT) applied to both the prostate and lymph nodes. Based on most recent studies, treatment intensification can be beneficial, but more randomised studies are needed. For pN1M0 PCa patients, adjuvant or early salvage treatments based on risk stratification determined by factors such as Gleason score, tumour stage, number of positive lymph nodes, and surgical margins appear to be the best-established treatment options. These treatments include close monitoring and adjuvant treatment with ADT and/or EBRT.

3D-Reconstructed Contact Surface Area and Tumour Volume on Magnetic Resonance Imaging Improve the Prediction of Extraprostatic Extension of Prostate Cancer

This study is to determine whether the volume and contact surface area (CSA) of a tumour with an adjacent prostate capsule on MRI in a three-dimensional (3D) model that can predict side-specific extraprostatic extension (EPE) at radical prostatectomy (RP). Patients with localised prostate cancer (PCa) who underwent robot-assisted RP between July 2015 and March 2021 were included in this retrospective study. MRI-based 3D prostate models incorporating the PCa volume and location were reconstructed. The tumour volume and surface variables were extracted. For the prostate-to-tumour and tumour-to-prostate CSAs, the areas in which the distances were ≤ 1, ≤ 2, ≤ 3, ≤ 4, and ≤ 5 mm were defined, and their surface (cm2) were determined. Differences in prostate sides with and without pathological EPE were analysed. Multivariable logistic regression analysis to find independent predictors of EPE. Overall, 75/302 (25%) prostate sides showed pathological EPE. Prostate sides with EPE had higher cT-stage, higher PSA density, higher percentage of positive biopsy cores, higher biopsy Gleason scores, higher radiological tumour stage, larger tumour volumes, larger prostate CSA, and larger tumour CSA (all p < 0.001). Multivariable logistic regression analysis showed that the radiological tumour stage (p = 0.001), tumour volume (p < 0.001), prostate CSA (p < 0.001), and tumour CSA (p ≤ 0.001) were independent predictors of pathological EPE. A 3D reconstruction of tumour locations in the prostate improves prediction of extraprostatic extension. Tumours with a higher 3D-reconstructed volume, a higher surface area of tumour in contact with the prostate capsule, and higher surface area of prostate capsule in contact with the tumour are at increased risk of side-specific extraprostatic extension.

The prognostic value of lymph node staging with prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) and extended pelvic lymph node dissection in node-positive patients with prostate cancer

OBJECTIVES

To investigate whether patients with suspected pelvic lymph node metastases (molecular imaging [mi] N1) on staging prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) had a different oncological outcome compared to those in whom the PSMA PET/CT did not reveal any pelvic lymph node metastases (miN0).

PATIENTS AND METHODS

All patients with pelvic lymph node metastatic (pN1) disease after robot-assisted radical prostatectomy (RARP) and extended pelvic lymph node dissection (ePLND) between January 2017 and December 2020 were included. To assess predictors of biochemical progression of disease after RARP, a multivariable Cox regression analysis was performed, including number of tumour-positive lymph nodes, diameter of the largest nodal metastasis, and extranodal extension.

RESULTS

In total, 145 patients were diagnosed with pN1 disease after ePLND. The median biochemical progression-free survival in patients with miN0 on PSMA PET/CT was 13.7 months, compared to 7.9 months in patients with miN1 disease (P = 0.006). On multivariable Cox regression analysis, both number of tumour-positive lymph nodes (>2 vs 1-2: hazard ratio [HR] 1.97; P = 0.005) and diameter of the largest nodal metastasis (HR 1.12; P < 0.001) were significant independent predictors of biochemical progression of disease.

CONCLUSION

Patients in whom pelvic lymph node metastases were suspected on preoperative PSMA imaging (miN1), patients diagnosed with >2 tumour-positive lymph nodes, and patients with a larger diameter of the largest nodal metastasis had a significantly increased risk of biochemical disease progression after surgery.

Genetic Aspects and Molecular Testing in Prostate Cancer: A Report from a Dutch Multidisciplinary Consensus Meeting

Background

Germline and tumour genetic testing in prostate cancer (PCa) is becoming more broadly accepted, but testing indications and clinical consequences for carriers in each disease stage are not yet well defined.

Objective

To determine the consensus of a Dutch multidisciplinary expert panel on the indication and application of germline and tumour genetic testing in PCa.

Design setting and participants

The panel consisted of 39 specialists involved in PCa management. We used a modified Delphi method consisting of two voting rounds and a virtual consensus meeting.

Outcome measurements and statistical analysis

Consensus was reached if ≥75% of the panellists chose the same option. Appropriateness was assessed by the RAND/UCLA appropriateness method.

Results and limitations

Of the multiple-choice questions, 44% reached consensus. For men without PCa having a relevant family history (familial PCa/BRCA-related hereditary cancer), follow-up by prostate-specific antigen was considered appropriate. For patients with low-risk localised PCa and a family history of PCa, active surveillance was considered appropriate, except in case of the patient being a BRCA2 germline pathogenic variant carrier. Germline and tumour genetic testing should not be done for nonmetastatic hormone-sensitive PCa in the absence of a relevant family history of cancer. Tumour genetic testing was deemed most appropriate for the identification of actionable variants, with uncertainty for germline testing. For tumour genetic testing in metastatic castration-resistant PCa, consensus was not reached for the timing and panel composition. The principal limitations are as follows: (1) a number of topics discussed lack scientific evidence, and therefore the recommendations are partly opinion based, and (2) there was a small number of experts per discipline.

Conclusions

The outcomes of this Dutch consensus meeting may provide further guidance on genetic counselling and molecular testing related to PCa.

Patient summary

A group of Dutch specialists discussed the use of germline and tumour genetic testing in prostate cancer (PCa) patients, indication of these tests (which patients and when), and impact of these tests on the management and treatment of PCa.

Identifying Patients in Whom the Follow-Up Scheme after Robot-Assisted Radical Prostatectomy Could Be Optimized in the First Year after Surgery: Reducing Healthcare Burden

Background: The currently advised follow-up scheme of PSA testing after robot-assisted radical prostatectomy (RARP) is strict and might pose a burden to our healthcare system. We aimed to optimize the 1-year follow-up scheme for patients who undergo RARP. Methods: All patients with histologically-proven prostate cancer (PCa) who underwent RARP between 2018 and August 2022 in the Prostate Cancer Network in the Netherlands were retrospectively evaluated. We excluded patients who underwent salvage RARP and patients who had <1 year of PSA follow-up. Postoperative PSA values were collected. Biochemical persistence (BCP) was defined as PSA level >0.10 ng/mL at 0–4 months after RARP, whereas biochemical recurrence (BCR) was defined as PSA level >0.2 ng/mL at any time point after RARP. We aimed to identify a group of patients who had a very low risk of BCR at different time points after surgery. Results: Of all 1155 patients, BCP was observed in 151 (13%), of whom 79 (6.8%) had PSA ≥ 0.2 ng/mL. BCR further developed in 51 (4.7%) and 37 (3.4%) patients at 5–8 and 9–12 months after RARP, respectively. In 12 patients, BCR was found at 5–8 months after RARP in the absence of BCP. These patients represented 1.2% (12/1004) of the entire group. In other words, 98.8% (992/1004) of patients who had an unmeasurable PSA level at 0–4 months after RARP also had an unmeasurable PSA level 5–8 months after surgery. Limitations are the retrospective design and incomplete follow-up. Conclusions: Patients with an unmeasurable PSA level at 3–4 months after RARP may not need to be retested until 12 months of follow-up, as almost 100% of patients will not have the biochemically recurrent disease at 5–8 months of follow-up. This will reduce PSA testing substantially at the cost of hardly any missed patients with recurrent disease.

Added Clinical Value of 18F-FDG-PET/CT to Stage Patients With High-Risk Non-Muscle Invasive Bladder Cancer Before Radical Cystectomy

INTRODUCTION AND OBJECTIVES

18F-fluorodeoxyglucose positron-emission tomography-computed tomography (FDG-PET/CT) is increasingly used in the preoperative staging of patients with muscle-invasive bladder cancer. The clinical added value of FDG-PET/CT in high-risk non-muscle invasive bladder cancer (NMIBC) is unknown. In this study, the value of FDG-PET/CT in addition to contrast enhanced (CE)-CT was evaluated in high-risk NMIBC before radical cystectomy (RC).

MATERIALS AND METHODS

This is a retrospective analysis of consecutive patients with high risk and very-high risk urothelial NMIBC scheduled for RC in a tertiary referral center between 2011 and 2020. Patients underwent staging with CE-CT (chest and abdomen/pelvis) and FDG-PET/CT. We assessed the clinical disease stage before and after FDG-PET/CT and the treatment recommendation based on the stage before and after FDG-PET/CT. The accuracy of CT and FDG-PET/CT for identifying metastatic disease was defined by the receiver-operating curve using a reference-standard including histopathology/cytology (if available), imaging and follow-up.

RESULTS

A total of 92 patients were identified (median age: 71 years). In 14/92 (15%) patients, FDG-PET/CT detected metastasis (12 suspicious lymph nodes and 4 distant metastases). The disease stage changed in 11/92 (12%) patients based on additional FDG-PET/CT findings. FDG-PET/CT led to a different treatment in 9/92 (10%) patients. According to the reference standard, 25/92 (27%) patients had metastases. The sensitivity, specificity and accuracy of FDG-PET/CT was 36%, 93% and 77% respectively, versus 12%, 97% and 74% of CE-CT only. The area under the ROC curve was 0.643 for FDG-PET/CT and 0.545 for CT, P = .036.

CONCLUSION

The addition of FDG-PET/CT to CE-CT imaging changed the treatment in 10% of patients and proved to be a valuable diagnostic tool in a selected subgroup of NMIBC patients scheduled for RC.

A prospective, multicenter head-to-head comparative study in patients with primary high-risk prostate cancer investigating the bone lesion detection of conventional imaging and 18F-PSMA-PET/CT

PURPOSE

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is an emerging staging tool for patients with primary high-risk prostate cancer (PCa). Patients with primary metastatic disease are staged using PSMA-PET/CT imaging, while previously published randomized clinical trials relied on conventional imaging (i.e., bone scintigraphy (BS) results. The aim of this study was to compare the ability of bone metastatic lesion detection and changes in staging for ¹⁸F-PSMA-PET/CT versus BS in high-risk PCa patients.

METHODS

79 patients with high-risk PCa were prospectively staged using BS and subsequent ¹⁸F-PSMA-PET/CT before initial therapy. Patients who presented with a BS showing no metastases represented Group 1, and patients with a BS showing low-volume disease according to the CHAARTED criteria (<4 bone metastases, no metastases outside vertebral column or pelvis and no visceral metastases) represented Group 2. Metastatic risk group according to CHAARTED and treatment strategies based on both imaging modalities were assessed.

RESULTS

A change of CHAARTED risk group was observed in 9/70 (12.8%) of patients in Group 1. In Group 2, a change of risk group was found in 66.7% of patients, due to either upstaging (4/9 patients (44.4%)) and downstaging (2/9 patients (22.2%)). Treatment changes due to use of a different imaging modality occurred in almost 20% of patients.

CONCLUSION

In patients with negative for cancer results on BS, upstaging on ¹⁸F-PSMA-PET/CT occurred only infrequently. Moreover, ¹⁸F-PSMA-PET/CT resulted in both upstaging and downstaging in a substantial subset of patients with low-volume metastatic disease on BS. Treatment changes occurred in almost 20% of cases depending on imaging results.

A standardized method to measure the membranous urethral length (MUL) on MRI of the prostate with high inter- and intra-observer agreement

OBJECTIVES

The membranous urethral length (MUL), defined as the length between the apex and penile base as measured on preoperative prostate magnetic resonance imaging (MRI), is an important predictor for urinary incontinence after radical prostatectomy. Literature on inter- and intra - observer agreement of MUL measurement is limited. We studied the inter- and intra-observer agreement between radiologists using a well-defined method to measure the MUL on the prostate MRI.

METHODS

Prostate cancer patients underwent a preoperative MRI and robot-assisted radical prostatectomy (RARP) at one high-volume RARP center. MUL measurement was based on well-defined landmarks on sagittal T2-weighted (anatomical) images. Three radiologists independently performed MUL measurements retrospectively in 106 patients blinded to themselves, to each other, and to clinical outcomes. The inter- and intra-observer agreement of MUL measurement between the radiologists were calculated, expressed as intra-class correlation coefficient (ICC).

RESULTS

The initial inter-observer agreement was ICC 0.63; 95% confidence interval (CI) 0.28-0.81. Radiologist 3 measured the MUL mean 3.9 mm (SD 3.3) longer than the other readers, interpreting the caudal point of the MUL (penile base) differently. After discussion on the correct anatomical definition, radiologist 3 re-assessed all scans, which resulted in a high inter-observer agreement (ICC 0.84; 95% CI 0.66-0.91). After a subsequent reading by radiologists 1 and 2, the intra-observer agreements were ICC 0.93; 95% CI 0.89-0.96, and ICC 0.98; 95% CI 0.97-0.98, respectively. Limitation is the monocenter design.

CONCLUSIONS

The MUL can be measured reliably with high agreement among radiologists.

KEY POINTS

• After discussion on the correct anatomical definition, the inter- and intra - observer agreements of membranous urethral length (MUL) measurement on magnetic resonance imaging (MRI) were high. • A reproducible method to measure the MUL can improve the clinical usefulness of prediction models for urinary continence after RARP which may benefit patient counselling.

Pharmacological Optimization of PSMA-Based Radioligand Therapy

Prostate cancer (PCa) is the most common malignancy in men of middle and older age. The standard treatment strategy for PCa ranges from active surveillance in low-grade, localized PCa to radical prostatectomy, external beam radiation therapy, hormonal treatment and chemotherapy. Recently, the use of prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) for metastatic castration-resistant PCa has been approved. PSMA is predominantly, but not exclusively, expressed on PCa cells. Because of its high expression in PCa, PSMA is a promising target for diagnostics and therapy. To understand the currently used RLT, knowledge about pharmacokinetics (PK) and pharmacodynamics (PD) of the PSMA ligand and the PSMA protein itself is crucial. PK and PD properties of the ligand and its target determine the duration and extent of the effect. Knowledge on the concentration-time profile, the target affinity and target abundance may help to predict the effect of RLT. Increased specific binding of radioligands to PSMA on PCa cells may be associated with better treatment response, where nonspecific binding may increase the risk of toxicity in healthy organs. Optimization of the radioligand, as well as synergistic effects of concomitant agents and an improved dosing strategy, may lead to more individualized treatment and better overall survival.

Development and clinical applicability of MRI-based 3D prostate models in the planning of nerve-sparing robot-assisted radical prostatectomy

The interpretation of conventional MRI may be limited by the two-dimensional presentation of the images. To develop patient-specific MRI prostate-based virtual and three-dimensional (3D)-printed models. To assess the association between 3D imaging and the pathological outcome of RARP specimen. To assess the clinical applicability of 3D models to guide nerve-sparing robot-assisted radical prostatectomy (RARP). We created virtual 3D and 3D-printed 3D models of 20 prostate cancer patients retrospectively. A comparison was made between conventional MRI and 3D-reconstructed images. The concordance between tumour lesion location in 3D models and pathology reporting of RARP specimens was assessed. Seven urologists assessed the side-specific extent of nerve-sparing based on (1) conventional MR images, (2) virtual 3D models, and (3) 3D-printed models. Clinically relevant changes in nerve-sparing and the absolute agreement between observers was analyzed using the Chi-square test and intra-class correlation coefficient (ICC). The index lesion was correctly visualized in 19/20 (95%) 3D models and the expected location of extraprostatic extension was correctly visualized in all 3D models. Clinically relevant changes in the planned extent of nerve-sparing between MRI and virtual 3D models and MRI and 3D-printed models were found in 25% and 26%. The ICC of the planned extent of nerve-sparing between urologists was 0.40 (95% CI 0.28-0.55) for conventional MRI, 0.52 (95% CI 0.39-0.66) for virtual 3D models and 0.58 (95% CI 0.45-0.71) for 3D-printed models. 3D models of the MRI prostate to guide RARP could aid urologists in the planning of nerve-sparing surgery as shown by a higher inter-observer agreement.

Comment on Rosenzweig et al. Very Low Prostate PET/CT PSMA Uptake May Be Misleading in Staging Radical Prostatectomy Candidates. J. Pers. Med. 2022, 12, 410

With interest, we read the article by Rosenzweig et al. [...].

Predictors of clinically significant prostate cancer in biopsy-naïve and prior negative biopsy men with a negative prostate MRI: improving MRI-based screening with a novel risk calculator

Purpose:

A pre-biopsy decision aid is needed to counsel men with a clinical suspicion for clinically significant prostate cancer (csPCa), despite normal prostate magnetic resonance imaging (MRI).

Methods:

A risk calculator (RC) for csPCa (International Society of Urological Pathology grade group (ISUP) ⩾ 2) presence in men with a negative-MRI (Prostate Imaging–Reporting and Data System (PI-RADS) ⩽ 2) was developed, and its performance was compared with RCs of the European Randomized Study of Screening for Prostate Cancer (ERSPC), Prostate Biopsy Collaborative Group (PBCG), and Prospective Loyola University mpMRI (PLUM). All biopsy-naïve and prior negative biopsy men with a negative-MRI followed by systematic prostate biopsy were included from October 2015 to September 2021. The RC was developed using multivariable logistic regression with the following parameters: age (years), family history of PCa (first- or second-degree family member), ancestry (African Caribbean/other), digital rectal exam (benign/malignant), MRI field strength (1.5/3.0 Tesla), prior negative biopsy status, and prostate-specific antigen (PSA) density (ng/ml/cc). Performance of RCs was compared using receiver operating characteristic (ROC) curve analysis.

Results:

A total of 232 men were included for analysis, of which 18.1% had csPCa. Parameters associated with csPCa were family history of PCa (p < 0.0001), African Caribbean ancestry (p = 0.005), PSA density (p = 0.002), prior negative biopsy (p = 0.06), and age at biopsy (p = 0.157). The area under the curve (AUC) of the developed RC was 0.76 (95% CI 0.68–0.85). This was significantly better than the RCs of the ERSPC (AUC: 0.59; p = 0.001) and PBCG (AUC: 0.60; p = 0.002), yet similar to PLUM (AUC: 0.69; p = 0.09).

Conclusion:

The developed RC (Prostate Biopsy Cohort Amsterdam (‘PROBA’ RC), integrated predictors for csPCa at prostate biopsy in negative-MRI men and outperformed other widely used RCs. These findings require external validation before introduction in daily practice.

Robot-assisted Prostate-specific Membrane Antigen-radioguided Salvage Surgery in Recurrent Prostate Cancer Using a DROP-IN Gamma Probe: The First Prospective Feasibility Study

BACKGROUND

It has been proven that intraoperative prostate-specific membrane antigen (PSMA)-targeted radioguidance is valuable for the detection of prostate cancer (PCa) lesions during open surgery. Rapid extension of robot-assisted, minimally invasive surgery has increased the need to make PSMA-radioguided surgery (RGS) robot-compliant.

OBJECTIVE

To evaluate whether the miniaturized DROP-IN gamma probe facilitates translation of PSMA-RGS to robotic surgery in men with recurrent PCa.

DESIGN, SETTING, AND PARTICIPANTS

This prospective feasibility study included 20 patients with up to three pelvic PCa recurrences (nodal or local) on staging PSMA positron emission tomography (PET) after previous curative-intent therapy.

SURGICAL PROCEDURE

Robot-assisted PSMA-RGS using the DROP-IN gamma probe was carried out 19-23 h after intravenous injection of ^99mtechnetium PSMA-Investigation & Surgery (^99mTc-PSMA-I&S).

MEASUREMENTS

The primary endpoint was the feasibility of robot-assisted PSMA-RGS. Secondary endpoints were a comparison of the radioactive status (positive or negative) of resected specimens and final histopathology results, prostate-specific antigen (PSA) response following PSMA-RGS, and complications according to the Clavien-Dindo classification.

RESULTS AND LIMITATIONS

Using the DROP-IN probe, 19/21 (90%) PSMA-avid lesions could be resected robotically. On a per-lesion basis, the sensitivity and specificity of robot-assisted PSMA-RGS was 86% and 100%, respectively. A prostate-specific antigen (PSA) reduction of >50% and a complete biochemical response (PSA <0.2 ng/ml) were seen in 12/18 (67%) and 4/18 (22%) patients, respectively. During follow-up of up to 15 mo, 4/18 patients (22%) remained free of biochemical recurrence (PSA ≤0.2 ng/ml). One patient suffered from a Clavien-Dindo grade >III complication.

CONCLUSIONS

The DROP-IN probe helps in realizing robot-assisted PSMA-RGS. The procedure is technically feasible for intraoperative detection of nodal or local PSMA-avid PCa recurrences.

PATIENT SUMMARY

A device called the DROP-IN probe facilitates minimally invasive, robot-assisted surgery guided by radioactive tracers in patients with recurrent prostate cancer. This procedure holds promise for improving the intraoperative identification and removal of prostate cancer lesions.

Trial-based Cost-effectiveness Analysis of an Immediate Postoperative Mitomycin C Instillation in Patients with Non–muscle-invasive Bladder Cancer

Background

Bladder cancer imposes a significant public health burden on the European Union. There is a need for cost-effective treatment and follow-up regimens.

Objective

To assess the cost-effectiveness of immediate mitomycin C (MMC) instillation within 1 d after surgery compared to delayed MMC instillation within 2 wk after surgery with further adjuvant treatment, depending on the patient’s risk group.

Design, setting, and participants

This economic evaluation was based on a randomized controlled trial among 2243 Dutch patients with non-muscle-invasive bladder cancer (NMIBC) patients from a health care perspective over a 3-yr time period.

Outcome measurements and statistical analysis

The treatment effect was measured as time to recurrence and recurrence-free survival. Missing effect data were imputed with multiple imputation. Health care utilization and related costs were estimated on the basis of treatment protocols for NMIBC patients in the Netherlands. Statistical uncertainty was estimated using bootstrapping and is graphically presented using cost-effectiveness planes and cost-effectiveness acceptability curves.

Results and limitations

Time to recurrence was significantly longer for immediate MMC instillation (27.31 mo) than for delayed MMC instillation (24.97 mo), with an adjusted mean difference of 2.21 mo (95% confidence interval [CI] 1.58–2.84). The proportion of patients with recurrence-free survival was significantly higher after immediate MMC instillation (0.65) than after delayed MMC instillation (0.56), with an adjusted mean difference of 0.08 (95% CI 0.06–0.11). Total mean health care costs per patient were significantly lower for immediate MMC instillation (€22 959) than for delayed MMC instillation (€24 624), with an adjusted mean difference of −€1350 (95% CI −€1799 to −€900). The study is limited by the retrospective estimation of costs.

Conclusions

This trial-based cost-effectiveness analysis shows that from a health care perspective, immediate MMC instillation is more effective and less expensive compared to delayed MMC instillation.

Patient summary

We assessed the cost-effectiveness of immediate bladder instillation of mitomycin C after surgery to reduce the risk of recurrence after removal of the bladder tumor as compared to delayed instillation in a large Dutch population of patients with non–muscle-invasive bladder cancer. We found that immediate instillation was more effective and less expensive than delayed instillation. We conclude that immediate mitomycin C instillation is a cost-effective treatment for non–muscle-invasive bladder cancer.

Standardised Uptake Values as Determined on PSMA PET/CT is associated with Oncological Outcomes in Prostate Cancer Patients

Objectives

To investigate the association between intraprostatic, intratumoral maximum standardised uptake values (SUV_max) on prostate‐specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in patients with prostate cancer (PCa) prior to robot‐assisted radical prostatectomy (RARP) and pathology outcomes, including pathological International Society of Urological Pathology score (pISUP) and lymph node (LN) status (pN0/pN1).

Patients and Methods

A bi‐centric, secondary analysis of two previous, prospective cohort studies was performed in 318 patients with biopsy confirmed PCa and who were scheduled for RARP. Before surgery, patients received a PSMA PET/CT with either ⁶⁸Ga‐PSMA‐11 (59% of the patients) or ¹⁸F‐PSMA (DCFPyL; 41%) as radiotracer. PET/CT images were analysed both visually and semi‐quantitatively by measuring the SUV_max of the most intense suspect lesion in the prostate. The association between the SUV_max of the primary tumour and pre‐ and postoperative variables was analysed.

Results

The SUV_max was associated with clinical and biopsy preoperative variables, as well as with pISUP score and pathological tumour stage. Patients with a pISUP of ≤2 showed significantly lower SUV_max compared to patients with a pISUP of >2 for both tracers (SUV_max¹⁸F‐PSMA: median 5.1 vs 9.6, P = 0.002; SUV_max⁶⁸Ga‐PSMA‐11: 6.6 vs 8.6, P = 0.003). Moreover, patients with pN1 had significantly higher median SUV_max than those with pN0/pNx for both tracers (SUV_max¹⁸F‐PSMA: 7.9 vs 12.3, P = 0.04; SUV_max⁶⁸Ga‐PSMA‐11: 7.6 vs 12.0, P < 0.001). On multivariable logistic regression analysis, the intraprostatic SUV_max was an independent predictor of pN1 for both ⁶⁸Ga‐PSMA‐11 (per doubling: odds ratio [OR] 1.96, 95% confidence interval [CI] 1.27–3.01)) and ¹⁸F‐PSMA (per doubling: OR 1.79, 95% CI 1.06–3.03).

Conclusion

Intraprostatic, intratumoral PSMA intensity on PET/CT, as semi‐quantitatively expressed by SUV_max, may be a valuable innovative biomarker in patients with localised PCa, as it is highly associated with known conventional prognostic factors, such as pISUP and LN status.

Bladder cancer detection in urine using DNA methylation markers: a technical and prospective preclinical validation

Background

The development of accurate urinary biomarkers for non-invasive and cost-effective detection of primary and recurrent bladder tumours is recognized as one of the major clinical needs in bladder cancer diagnostics. The purposes of this study were (1) to validate the results of a previous technical comparison by determining the diagnostic performance of nine methylation markers in urine pellet compared to full void urine, and (2) to validate the diagnostic performance of the optimal marker panel GHSR/MAL from a previous exploratory study in a preclinical setting.

Methods

Urine samples of 108 patients with bladder cancer and 100 age- and gender-matched controls were prospectively collected for methylation analysis. Urinary methylation levels of the markers FAM19A4, GHSR, MAL, miR-129, miR-935, PHACTR3, PRDM14, SST and ZIC1 were determined with quantitative methylation-specific PCR in urine pellet. Area under the curves (AUCs) were determined for individual markers and the marker panel GHSR/MAL. The diagnostic performance of the marker panel GHSR/MAL was evaluated in the total study population and in different subgroups of patients with bladder cancer using the Chi-square test. The diagnostic accuracy was assessed by leave-one-out cross-validation.

Results

All nine urinary methylation markers (FAM19A4, GHSR, MAL, miR-129, miR-935, PHACTR3, PRDM14, SST and ZIC1) showed significantly higher methylation levels in bladder cancer patients than in controls (p < 0.001). Area under the curves (AUCs) of the nine methylation markers tested in urine pellet were similar to AUCs in full void urine of an independent previous cohort. GHSR/MAL reached an AUC of 0.89 (95% confidence interval [CI] 0.84–0.94), at 80% sensitivity and 93% specificity. Sensitivity of GHSR/MAL increased with higher tumour grades, higher tumour stages, in primary vs. recurrent tumours, and in males vs. females.

Conclusions

This technical validation supports the robustness of DNA methylation analysis in urine pellet and full void urine for the non-invasive detection of bladder cancer. Subsequent preclinical validation confirmed the diagnostic potential of GHSR/MAL. These findings underline the diagnostic potential of the marker panel GHSR/MAL for future bladder cancer diagnostics.

The detection rate of apical tumour involvement on preoperative MRI and its impact on clinical outcomes in patients with localized prostate cancer

To determine the diagnostic performance of radiological apical tumour involvement (radATI) in preoperative prostate MRI, referenced to pathological ATI (pathATI) at radical prostatectomy specimens. To investigate risk factors for apical positive surgical margins (APSM). A retrospective cohort of consecutive patients with biopsy-proven PCa who underwent MRI and robot-assisted radical prostatectomy between July 2015 and March 2020 was studied (n = 177). Clinical, imaging, pathology, oncology and functional data were retrieved. The diagnostic accuracy of MRI to detect pathATI was analysed. Multivariate logistic regression was used to find independent predictors for APSM. radATI and pathATI was found in 121 (68%) and 161 (91%) patients, respectively. The diagnostic metrics of sensitivity, specificity, PPV, and NPV were 69, 38, 92, and 11%, respectively. APSM were present in 43 (24%) patients. Patients with radATI were more likely to have APSM (37/121 (31%)) than those without radATI (6/56 (11%)) (OR 3.67 [95% CI 1.45-9.31], p = 0.004). This was confirmed in multivariate analysis. Only 2/56 (4%) patients without radATI developed a biochemical recurrence compared to 25/120 (21%) patients with radATI (hazard ratio 6.68 [95% CI 3.03-14.8], p = 0.003). Prostate cancer extends into the apex in the majority of cases. Clinicians are advised to report on the presence or absence of radiological apical tumour involvement as it is an independent risk factor for apical positive surgical margins and is even associated with biochemical recurrence.

Selection of patients for nerve sparing surgery in robot‐assisted radical prostatectomy

Context

Robot‐assisted radical prostatectomy (RARP) has become the standard surgical procedure for localized prostate‐cancer (PCa). Nerve‐sparing surgery (NSS) during RARP has been associated with improved erectile function and continence rates after surgery. However, it remains unclear what are the most appropriate indications for NSS.

Objective

The objective of this study is to systematically review the available parameters for selection of patients for NSS. The weight of different clinical variables, multiparametric magnetic‐resonance‐imaging (mpMRI) findings, and the impact of multiparametric‐nomograms in the decision‐making process on (side‐specific) NSS were assessed.

Evidence acquisition

This systematic review searched relevant databases and included studies performed from January 2000 until December 2020 and recruited a total of 15 840 PCa patients. Studies were assessed that defined criteria for (side‐specific) NSS and associated them with oncological safety and/or functional outcomes. Risk of bias assessment was performed.

Evidence synthesis

Nineteen articles were eligible for full‐text review. NSS is primarily recommended in men with adequate erectile function, and with low‐risk of extracapsular extension (ECE) on the side‐of NSS. Separate clinical and radiological variables have low accuracy for predicting ECE, whereas nomograms optimize the risk‐stratification and decision‐making process to perform or to refrain from NSS when oncological safety (organ‐confined disease, PSM rates) and functional outcomes (erectile function and continence rates) were assessed.

Conclusions

Consensus exists that patients who are at high risk of ECE should refrain from NSS. Several multiparametric preoperative nomograms were developed to predict ECE with increased accuracy compared with single clinical, pathological, or radiological variables, but controversy exists on risk thresholds and decision rules on a conservative versus a less‐conservative surgical approach. An individual clinical judgment on the possibilities of NSS set against the risks of ECE is warranted.

Patient summary

NSS is aimed at sparing the nerves responsible for erection. NSS may lead to unfavorable tumor control if the risk of capsule penetration is high. Nomograms predicting extraprostatic tumor‐growth are probably most helpful.

Update to a randomized controlled trial of lutetium-177-PSMA in Oligo-metastatic hormone-sensitive prostate cancer: the BULLSEYE trial

BACKGROUND

The BULLSEYE trial is a multicenter, open-label, randomized controlled trial to test the hypothesis if ¹⁷⁷Lu-PSMA is an effective treatment in oligometastatic hormone-sensitive prostate cancer (oHSPC) to prolong the progression-free survival (PFS) and postpone the need for androgen deprivation therapy (ADT). The original study protocol was published in 2020. Here, we report amendments that have been made to the study protocol since the commencement of the trial.

CHANGES IN METHODS AND MATERIALS

Two important changes were made to the original protocol: (1) the study will now use ¹⁷⁷Lu-PSMA-617 instead of ¹⁷⁷Lu-PSMA-I&T and (2) responding patients with residual disease on ¹⁸F-PSMA PET after the first two cycles are eligible to receive additional two cycles of 7.4 GBq ¹⁷⁷Lu-PSMA in weeks 12 and 18, summing up to a maximum of 4 cycles if indicated. Therefore, patients receiving ¹⁷⁷Lu-PSMA-617 will also receive an interim ¹⁸F-PSMA PET scan in week 4 after cycle 2. The title of this study was modified to; "Lutetium-177-PSMA in Oligo-metastatic Hormone Sensitive Prostate Cancer" and is now partly supported by Advanced Accelerator Applications, a Novartis Company.

CONCLUSIONS

We present an update of the original study protocol prior to the completion of the study. Treatment arm patients that were included and received ¹⁷⁷Lu-PSMA-I&T under the previous protocol will be replaced.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04443062 . First posted: June 23, 2020.

Prospective analysis of clinically significant prostate cancer detection with [18F]DCFPyL PET/MRI compared to multiparametric MRI: a comparison with the histopathology in the radical prostatectomy specimen, the ProStaPET study

PURPOSE

Multiparametric magnetic resonance imaging (mpMRI) is a well-established imaging method for localizing primary prostate cancer (PCa) and for guiding targeted prostate biopsies. [¹⁸F]DCFPyL positron emission tomography combined with MRI (PSMA-PET/MRI) might be of additional value to localize primary PCa. The aim of this study was to assess the diagnostic performance of [¹⁸F]DCFPyL-PET/MRI vs. mpMRI in tumour localization based on histopathology after robot-assisted radical-prostatectomy (RARP), also assessing biopsy advice for potential image-guided prostate biopsies.

METHODS

Thirty prospectively included patients with intermediate to high-risk PCa underwent [¹⁸F]DCFPyL-PET/MRI and mpMRI prior to RARP. Two nuclear medicine physicians and two radiologists assessed tumour localization on [¹⁸F]DCFPyL-PET/MRI and on mpMRI respectively, and gave a prostate biopsy advice (2 segments) using a 14-segment model of the prostate. The uro-pathologist evaluated the RARP specimen for clinically significant PCa (csPCa) using the same model. csPCa was defined as any PCa with Grade Group (GG) ≥ 2. The biopsy advice based on imaging was correlated with the final histology in the RARP specimen for a total-agreement analysis. An additional near-agreement correlation was performed to approximate clinical reality.

RESULTS

Overall, 142 of 420 (33.8%) segments contained csPCa after pathologic examination. The segments recommended for targeted biopsy contained the highest GG PCa segment in 27/30 patients (90.0%) both for [¹⁸F]DCFPyL-PET/MRI and mpMRI. Areas under the receiver operating characteristics curves (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the total-agreement detection of csPCa per segment using [¹⁸F]DCFPyL-PET/MRI were 0.70, 50.0%, 89.9%, 71.7%, and 77.9%, respectively. These results were 0.75, 54.2%, 94.2%, 82.8%, and 80.1%, respectively, for mpMRI only.

CONCLUSION

Both [¹⁸F]DCFPyL-PET/MRI and mpMRI were only partly able to detect csPCa on a per-segment basis. An accurate detection (90.0%) of the highest GG lesion at patient-level was observed when comparing both [¹⁸F]DCFPyL-PET/MRI and mpMRI biopsy advice with the histopathology in the RARP specimen. So, despite the finding that [¹⁸F]DCFPyL-PET/MRI adequately detects csPCa, it does not outperform mpMRI.

Prediction of pathological response following neoadjuvant chemotherapy in patients with muscle-invasive bladder cancer: the PRE-PREVENCYS trial

Background

The recommended treatment for patients with non-metastatic muscle-invasive bladder cancer (MIBC) is neoadjuvant chemotherapy (NAC) and radical cystectomy (RC). Following NAC, 20–40% of patients experience a complete pathological response (pCR) in the RC specimen and these patients have excellent long-term overall survival. Subject to debate is, however, whether patients with a pCR to NAC benefit from RC, which is a major surgical procedure with substantial morbidity, and if these patients might be candidates for close surveillance instead. However, currently it is not possible to accurately identify patients with a pCR to NAC in whom RC might be withheld. The objective of this study is to assess whether pathological response in the RC specimen after NAC can be predicted based on clinical, radiological, and histological variables and on a wide set of molecular biomarkers assessed in tissue, blood and urine.

Methods

This is a multicentre, prospective cohort study, including patients with cT2a-T4a N0-N1 M0 urothelial cell MIBC who are scheduled to undergo cisplatin-based NAC followed by RC. Prior to start of therapy, a 2-Deoxy-2-[18F] fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) is performed. Response to NAC is evaluated by CT-scan. Blood and urine, including cytology, are prospectively collected for biomarker analyses before and after NAC. Immediately before RC, participants undergo cystoscopy with bimanual examination and a re-staging transurethral resection (TUR) of all visible cancerous lesions or with biopsies from scar tissue. Subsequently, RC is performed in all patients. Tissue from the diagnostic TUR, the re-staging TUR, and the RC specimen is examined for the presence of urothelial cancer carcinoma and DNA and RNA is isolated for molecular analysis. The primary endpoint is the pathological stage (ypTN) in the RC and ePLND specimen and its association with clinical response.

Discussion

If the PRE-PREVENCYS trial shows that the absence of residual disease after NAC in patients with MIBC is accurately predicted, a randomized controlled trial is scheduled comparing the overall survival of NAC plus RC versus NAC followed by close surveillance for patients with a clinically complete response (PREVENCYS trial).

Trial registration

Netherlands Trial Register: NL8678; Registered 20 May 2020 https://www.trialregister.nl/trial/8678

SUVs Are Adequate Measures of Lesional 18F-DCFPyL Uptake in Patients with Low Prostate Cancer Disease Burden

In prostate cancer (PCa) patients, the tumor-to-blood ratio (TBR) has been validated as the preferred simplified method for lesional ¹⁸F-DCFPyL (a radiolabeled prostate-specific membrane antigen ligand) uptake quantification on PET. In contrast to SUVs, the TBR accounts for variability in arterial input functions caused by differences in total tumor burden between patients (the sink effect). However, TBR depends strongly on tracer uptake interval and has worse repeatability and is less applicable in clinical practice than SUVs. We investigated whether SUV could provide adequate quantification of ¹⁸F-DCFPyL uptake on PET/CT in a patient cohort with low PCa burden. Methods: In total, 116 patients with PCa undergoing ¹⁸F-DCFPyL PET/CT imaging were retrospectively included. All ¹⁸F-DCFPyL-avid lesions suspected of being PCa were semiautomatically delineated. SUV_peak was plotted against TBR for the most intense lesion of each patient. The correlation of SUV_peak and TBR was evaluated using linear regression and was stratified for patients undergoing PET/CT for primary staging, patients undergoing restaging at biochemical recurrence, and patients with metastatic castration-resistant PCa. Moreover, the correlation was evaluated as a function of tracer uptake time, prostate-specific antigen level, and PET-positive tumor volume. Results: In total, 436 lesions were delineated (median, 1 per patient; range, 1-66). SUV_peak correlated well with TBR in patients with PCa and a total tumor volume of less than 200 cm³ (R ² = 0.931). The correlation between SUV and TBR was not affected by disease setting, prostate-specific antigen level, or tumor volume. SUV_peak depended less on tracer uptake time than did TBR. Conclusion: For ¹⁸F-DCFPyL PET/CT, SUV_peak correlates strongly with TBR. Therefore, it is a valuable simplified, semiquantitative measurement in patients with low-volume PCa (<200 cm³). SUV_peak can therefore be applied in ¹⁸F-DCFPyL PET assessment as an imaging biomarker to characterize tumors and to monitor treatment outcomes.

Determining the diagnostic value of PSMA-PET/CT imaging in patients with persistent high prostate specific antigen levels and negative prostate biopsies

PURPOSE

To assess the diagnostic performance of prostate specific membranous antigen (PSMA) positron emission tomography/computed tomography (PET/CT) imaging to localize primary prostate cancer (PCa) in men with persistent elevated prostate-specific antigen (PSA) levels and previous prostate biopsies that were negative for PCa.

METHODS

In this study, 34 men with persistently elevated PSA-levels, previous negative for PCa biopsies and who subsequently underwent diagnostic PSMA-PET/CT imaging were retrospectively evaluated. Men were divided into 3 groups: 1. 12 men with a previous negative mpMRI scan (PI-RADS 1-2) 2. 17 men with a positive mpMRI scan (PI-RADS 3-5), but negative MRI-targeted biopsies and 3. Four men in whom mpMRI was contraindicated. If PSMA-avid lesions were seen, patients underwent 2-4 cognitive targeted biopsies in combination with systematic biopsies. The detection rate of PSMA-PET/CT for PCa, and the accuracy of (possible) targeted biopsies were calculated.

RESULTS

Included men had a median PSA-level of 22.8 ng/mL (Interquartile Range 15.6-30.0) at the time of PSMA-PET/CT. Elevated PSMA-ligand uptake in the prostate suspicious for PCa was observed in 22/34 patients (64.7%). In 18/22 patients (54.5%), PSMA-targeted prostate biopsies were performed. In 3/18 patients (16.6%), the targeted biopsies showed International Society of Urological Pathology (ISUP) score 1-2 PCa. The other men had inflammation or benign findings after histopathological examination of the biopsy cores.

CONCLUSION

In this study, the clinical value of PSMA-PET/CT for patients with an elevated PSA-level, and negative for PCa biopsies was low. Only very few men were diagnosed with PCa, and no clinically significant PCa was found.

Patient reported outcome measures concerning urinary incontinence after robot assisted radical prostatectomy: development and validation of an online prediction model using clinical parameters, lower urinary tract symptoms and surgical experience

The prediction of post-prostatectomy incontinence (PPI) after robot-assisted radical prostatectomy (RARP) depends on multiple clinical, anatomical and surgical factors. There are only few risk formulas, tables or nomograms predicting PPI that may assist clinicians and their patients in adequate risk counseling on postoperative side-effects. Prospective data collection of 1814 patients who underwent RARP between 2009 and 2017 was done. Pre-operative parameters were age, body mass index (BMI), prostate volume, the American Society of Anesthesiologists (ASA) score, severity of Lower Urinary Tract Symptoms (LUTS), type of planned nerve-sparing surgery and surgical experience. The continence status was reported using Patient Reported Outcome Measurements (PROMs) using the validated pad-use questionnaire EPIC26. Continence was defined as either the use of zero pads or one safety pad. Multivariable logistic regression analysis was performed to identify predictors of PPI within one year after RARP. An online prediction tool was developed and validated. The median follow-up was 36 months (range 12-108). The response rate was high at 85.2%. A total of 85% (1537/1814) of patients was continent on follow-up. One-year continence rate was 80.1% (95% CI 78.3-81.9%) (1453/1814) and increased to 87.4% (95% CI 85.4-89.4%) after 5 years. On multivariable analysis, severity of LUTS (OR = 0.56 p = 0.004), higher age (OR = 0.73 p = 0.049), extend of nerve-sparing surgery (OR = 0.60 p = 0.001) and surgeon experience (OR = 1.48 p = 0.025) were significant independent predictors for PPI. The online prediction model performed well in predicting continence status with poor discrimination and good calibration. An intuitive online tool was developed to predict PPI after RARP that may assist clinicians and their patients in counseling of treatment.

Intermediate-term survival of robot-assisted versus open radical cystectomy for muscle-invasive and high-risk non-muscle invasive bladder cancer in The Netherlands

BACKGROUND

Radical cystectomy with pelvic lymph node dissection is the recommended treatment in non-metastatic muscle-invasive bladder cancer (MIBC). In randomised trials, robot-assisted radical cystectomy (RARC) showed non-inferior short-term oncological outcomes compared with open radical cystectomy (ORC). Data on intermediate and long-term oncological outcomes of RARC are limited.

OBJECTIVE

To assess the intermediate-term overall survival (OS) and recurrence-free survival (RFS) of patients with MIBC and high-risk non-MIBC (NMIBC) who underwent ORC versus RARC in clinical practice.

METHODS AND MATERIALS

A nationwide retrospective study in 19 Dutch hospitals including patients with MIBC and high-risk NMIBC treated by ORC (n = 1086) or RARC (n = 386) between January 1, 2012 and December 31, 2015. Primary and secondary outcome measures were median OS and RFS, respectively. Survival outcomes were estimated using Kaplan-Meier curves. A multivariable Cox regression model was developed to adjust for possible confounders and to assess prognostic factors for survival including clinical variables, clinical and pathological disease stage, neoadjuvant therapy and surgical margin status.

RESULTS

The median follow-up was 5.1 years (95% confidence interval ([95%CI] 5.0-5.2). The median OS after ORC was 5.0 years (95%CI 4.3-5.6) versus 5.8 years after RARC (95%CI 5.1-6.5). The median RFS was 3.8 years (95%CI 3.1-4.5) after ORC versus 5.0 years after RARC (95%CI 3.9-6.0). After multivariable adjustment, the hazard ratio for OS was 1.00 (95%CI 0.84-1.20) and for RFS 1.08 (95%CI 0.91-1.27) of ORC versus RARC. Patients who underwent ORC were older, had higher preoperative serum creatinine levels and more advanced clinical and pathological disease stage.

CONCLUSION

ORC and RARC resulted in similar intermediate-term OS and RFS in a cohort of almost 1500 MIBC and high-risk NMIBC.

Predicting early outcomes in patients with intermediate- and high-risk prostate cancer using prostate-specific membrane antigen positron emission tomography and magnetic resonance imaging

Objectives

To identify predictors of early oncological outcomes in patients who opt for robot‐assisted laparoscopic radical prostatectomy (RARP) for localized prostate cancer (PCa), including conventional prognostic variables as well as multiparametric magnetic resonance imaging (mpMRI) and prostate‐specific membrane antigen (PSMA) positron emission tomography (PET).

Patients and Methods

This observational study included 493 patients who underwent RARP and extended pelvic lymph node dissection (ePLND) for unfavourable intermediate‐ or high‐risk PCa. Outcome measurement was biochemical progression of disease, defined as any postoperative prostate‐specific antigen (PSA) value ≥0.2 ng/mL, or the start of additional treatment. Cox regression analysis was performed to assess predictors for biochemical progression, including initial PSA value, biopsy Grade Group (GG), T‐stage on mpMRI, and lymph node status on PSMA PET imaging (miN0 vs miN1).

Results

The median (interquartile range) total follow‐up of all included patients without biochemical progression was 12.6 (7.5–22.7) months. When assessing biochemical progression after surgery, initial PSA value (per doubling; odds ratio [OR] 1.22, 95% confidence interval [CI] 1.07–1.40; P = 0.004), biopsy GG ≥4 vs GG 1–2 (OR 1.83, 95% CI 1.18–2.85; P = 0.007), T‐stage on mpMRI (rT3a vs rT2: OR 2.13, 95% CI 1.39–3.27; P = 0.001; ≥rT3b vs rT2: OR 4.78, 95% CI 3.20–7.16; P < 0.001) and miN1 on PSMA PET imaging (OR 2.94, 95% CI 2.02–4.27; P < 0.001) were independent predictors of early biochemical progression of disease.

Conclusion

Initial PSA value, biopsy GG ≥4, ≥rT3 disease on mpMRI and miN1 disease on PSMA PET were predictors of early biochemical progression after RARP. Identifying these patients with an increased risk of early biochemical progression after surgery may have major implications for patient counselling in radical treatment decisions and on patient selection for modern (neo‐)adjuvant and systematic treatments.

External Validation and Addition of Prostate-specific Membrane Antigen Positron Emission Tomography to the Most Frequently Used Nomograms for the Prediction of Pelvic Lymph-node Metastases: an International Multicenter Study

BACKGROUND

Different nomograms exist for the preoperative prediction of pelvic lymph-node metastatic disease in individual patients with prostate cancer (PCa). These nomograms do not incorporate modern imaging techniques such as prostate-specific membrane antigen (PSMA) positron emission tomography (PET).

OBJECTIVE

To determine the predictive performance of the Briganti 2017, Memorial Sloan Kettering Cancer Center (MSKCC), and Briganti 2019 nomograms with the addition of PSMA-PET in an international, multicenter, present-day cohort of patients undergoing robot-assisted radical prostatectomy (RARP) and extended pelvic lymph-node dissection (ePLND) for localized PCa.

DESIGN, SETTING, AND PARTICIPANTS

All 757 eligible patients who underwent a PSMA-PET prior to RARP and ePLND in three reference centers for PCa surgery between January 2016 and November 2020 were included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Performance of the three nomograms was assessed using the receiver operating characteristic curve-derived area under the curve (AUC), calibration plots, and decision curve analyses. Subsequently, recalibration and addition of PSMA-PET to the nomograms were performed.

RESULTS AND LIMITATIONS

Overall, 186/757 patients (25%) had pelvic lymph-node metastatic (pN1) disease on histopathological examination. AUCs of the Briganti 2017, MSKCC, and Briganti 2019 nomograms were 0.70 (95% confidence interval [95% CI]: 0.64-0.77), 0.71 (95% CI: 0.65-0.77), and 0.76 (95% CI: 0.71-0.82), respectively. PSMA-PET findings showed a significant association with pN1 disease when added to the nomograms (p < 0.001). Addition of PSMA-PET substantially improved the discriminative ability of the models yielding cross-validated AUCs of 0.76 (95% CI: 0.70-0.82), 0.77 (95% CI: 0.72-0.83), and 0.82 (95% CI: 0.76-0.87), respectively. In decision curve analyses, the addition of PSMA-PET to the three nomograms resulted in increased net benefits.

CONCLUSIONS

The addition of PSMA-PET to the previously developed nomograms showed substantially improved predictive performance, which suggests that PSMA-PET is a likely future candidate for a modern predictive nomogram.

PATIENT SUMMARY

Different tools have been developed to individualize the prediction of prostate cancer spread to lymph nodes before surgery. We found that the inclusion of modern imaging (prostate-specific membrane antigen positron emission tomography) improved substantially the overall performance of these prediction tools.

External Validation of Two Nomograms Developed for 68Ga-PSMA-11 Applied to the Prostate-specific Membrane Antigen Tracer 18F-DCFPyl: Is Prediction of the Optimal Timing of Salvage Therapy Feasible?

Two nomograms have been developed to predict the outcome of positron emission tomography (PET)/computed tomography (CT) imaging with⁶⁸Ga-labeled ligands for prostate-specific membrane antigen (⁶⁸Ga-PSMA) for patients with rising prostate-specific antigen after radical prostatectomy (RP). These nomograms quantify the ability of PSMA PET/CT to detect prostate cancer recurrences, and therefore provide critical information in determining the optimal timing for PSMA PET/CT in guiding salvage therapies. We validated the ability of these nomograms to accurately predict PET/CT outcome using another ligand tracer, ¹⁸F-DCFPyL. The external validation cohort consisted of 157 men from the Prostate Cancer Network Netherlands who underwent ¹⁸F-DCFPyL PET/CT to guide salvage therapies after RP. The nomogram of Rauscher et al (predicting a positive scan) showed accurate prediction of 50–80% (discrimination 0.68, 95% confidence interval [CI] 0.59–0.76). The nomogram of Luiting et al (predicting recurrence outside the prostatic fossa) showed accurate prediction for predicted probability values between 15% and 65%, with a small degree of overestimation for predicted probability values between 30% and 50% (discrimination 0.74, 95% CI 0.28–1.24). According to calibration curves, discrimination results, and decision curve analysis, we conclude that clinicians can use these ⁶⁸Ga-PSMA–based nomograms to predict ¹⁸F-DCFPyL PET/CT outcome. These nomograms improve shared decision-making in determining the optimal time to initiate PSMA PET/CT–guided salvage therapies.

Patient summary

Prediction tools developed for prostate scans (positron emission tomography, PET) using one type of radioactive tracer (chemicals labeled with gallium-68) are also accurate in predicting scan findings with another tracer (a chemical labeled with fluorine-18). Our study confirms that these tools can be used to guide decisions on the timing of treatments for prostate cancer recurrence.

Preoperative multiparametric MRI does not lower positive surgical margin rate in a large series of patients undergoing robot-assisted radical prostatectomy

To optimize functional outcomes after robot-assisted radical prostatectomy (RARP), surgical preservation of the neurovascular bundle is desired. However, nerve-sparing surgery (NSS) is only feasible in the absence of extraprostatic tumour extension (T-stage 3) to avoid the risk of positive surgical margins (PSM). Multiparametric magnetic-resonance imaging (MRI) is increasingly performed for primary prostate cancer and provides information on local tumour stage. In this study, we evaluated whether the availability of information from MRI influenced the incidence of PSM. A total of 523 patients undergoing RARP for localized prostate cancer in a single Dutch reference centre for prostate-cancer surgery were retrospectively evaluated (2013-2017). Patient characteristics and postoperative outcomes were retrieved. Patients were stratified according to the presence of a preoperative MRI. The incidence of PSM and proportion of patients receiving NSS was analysed using Chi-square tests and logistic regression analysis. N = 139 of 523 (26.6%) patients had a preoperative MRI scan available. Patients with MRI had identical preoperative characteristics compared to the patients without MRI, except for a higher percentage of patients having a prostate-specific antigen value ≥ 20 ng/mL (20.1% versus 9.4%, p = 0.004). PSM were present in 107/384 (27.9%) patients without MRI compared to 36/139 (25.9%) patients with an MRI scan before surgery (p = 0.66). Unilateral NSS was performed more often in the MRI group (26.6% vs. 11.7%), but NSS on both sides was more frequently performed in patients without MRI (57.6% versus 69.8%) (p < 0.001). MRI was not associated with PSM in multivariate analysis (p = 0.265). Preoperative mpMRI imaging was not associated with lower rates of positive surgical margins in patients undergoing RARP for localized prostate cancer.

Pelvic lymph-node staging with 18F-DCFPyL PET/CT prior to extended pelvic lymph-node dissection in primary prostate cancer - the SALT trial

PURPOSE

The detection of lymph-node metastases (N1) with conventional imaging such as magnetic resonance imaging (MRI) and computed tomography (CT) is inadequate for primarily diagnosed prostate cancer (PCa). Prostate-specific membrane antigen (PSMA) PET/CT is successfully introduced for the staging of (biochemically) recurrent PCa. Besides the frequently used 68gallium-labelled PSMA tracers, 18fluorine-labelled PSMA tracers are available. This study examined the diagnostic accuracy of 18F-DCFPyL (PSMA) PET/CT for lymph-node staging in primary PCa.

METHODS

This was a prospective, multicentre cohort study. Patients with primary PCa underwent 18F-DCFPyL PET/CT prior to robot-assisted radical prostatectomy (RARP) with extended pelvic lymph-node dissection (ePLND). Patients were included between October 2017 and January 2020. A Memorial Sloan Kettering Cancer Centre (MSKCC) nomogram risk probability of ≥ 8% of lymph-node metastases was set to perform ePLND. All images were reviewed by two experienced nuclear physicians, and were compared with post-operative histopathologic results.

RESULTS

A total of 117 patients was analysed. Lymph-node metastases (N1) were histologically diagnosed in 17/117 patients (14.5%). The sensitivity, specificity, positive predictive value and negative predictive value for the 18F-DCFPyL PET/CT detection of pelvic lymph-node metastases on a patient level were 41.2% (confidence interval (CI): 19.4-66.5%), 94.0% (CI 86.9-97.5%), 53.8% (CI 26.1-79.6%) and 90.4% (CI 82.6-95.0%), respectively.

CONCLUSION

18F-DCFPyL PET/CT showed a high specificity (94.4%), yet a limited sensitivity (41.2%) for the detection of pelvic lymph-node metastases in primary PCa. This implies that current PSMA PET/CT imaging cannot replace diagnostic ePLND. Further research is necessary to define the exact place of PSMA PET/CT imaging in the primary staging of PCa.

Nuclear Imaging for Bone Metastases in Prostate Cancer: The Emergence of Modern Techniques Using Novel Radiotracers

Accurate staging of prostate cancer (PCa) at initial diagnosis and at biochemical recurrence is important to determine prognosis and the optimal treatment strategy. To date, treatment of metastatic PCa has mostly been based on the results of conventional imaging with abdominopelvic computed tomography (CT) and bone scintigraphy. However, these investigations have limited sensitivity and specificity which impairs their ability to accurately identify and quantify the true extent of active disease. Modern imaging modalities, such as those based on the detection of radioactively labeled tracers with combined positron emission tomography/computed tomography (PET/CT) scanning have been developed specifically for the detection of PCa. Novel radiotracers include ¹⁸F-sodium fluoride (NaF), ¹¹C-/¹⁸F-fluorocholine (FCH), ¹⁸F-fluordihydrotestosterone (FDHT), ⁶⁸Gallium and ¹⁸F-radiolabeled prostate-specific membrane antigen (e.g., ⁶⁸Ga-PSMA-11, ¹⁸F-DCFPyL). PET/CT with these tracers outperforms conventional imaging. As a result of this, although their impact on outcome needs to be better defined in appropriate clinical trials, techniques like prostate-specific membrane antigen (PSMA) PET/CT have been rapidly adopted into clinical practice for (re)staging PCa. This review focuses on nuclear imaging for PCa bone metastases, summarizing the literature on conventional imaging (focusing on CT and bone scintigraphy—magnetic resonance imaging is not addressed in this review), highlighting the prognostic importance of high and low volume metastatic disease which serves as a driver for the development of better imaging techniques, and finally discussing modern nuclear imaging with novel radiotracers.