Active Surveillance for Prostate Cancer: A Systematic Review of the Literature

The Impact of Delayed Radical Prostatectomy on Recurrence Outcomes After Initial Active Surveillance: Results from a Large Institutional Cohort

BACKGROUND AND OBJECTIVE

Active surveillance (AS) of prostate cancer (PCa) involves regular monitoring for disease progression. The aim is to avoid unnecessary treatment while ensuring appropriate and timely treatment for those whose disease progresses. AS has emerged as the standard of care for low-grade (Gleason grade 1, GG 1) PCa. Opponents are concerned that initial undersampling and delay of definitive management for patients with GG 2 disease may lead to adverse outcomes. We sought to determine whether the timing for definitive management of GG 2 PCa, either upfront or after initial AS, affects recurrence outcomes after radical prostatectomy (RP).

METHODS

Participants were diagnosed with cT1-2N0/xM0/x, prostate-specific antigen (PSA) <20 ng/ml, and GG 1-2 PCa between 2000 and 2020 and underwent immediate RP for GG 2 or AS followed by delayed RP on upgrading to GG 2. The outcome was recurrence-free survival (RFS) after surgery, with recurrence defined as either biochemical failure (2 PSA measurements ≥0.2 ng/ml) or a second treatment. Multivariable Cox proportional-hazards regression models were used to calculate associations between the timing for definitive RP and the risk of recurrence, adjusted for age at diagnosis, percentage of positive biopsy cores (PPC), PSA density, PSA before RP, year of diagnosis, surgical margins, genomic risk score, and prostate MRI findings.

KEY FINDINGS

Of the 1259 men who met the inclusion criteria, 979 underwent immediate RP after diagnosis of GG 2, 190 underwent RP within 12 mo of upgrading to GG 2 on AS, and 90 men underwent RP >12 mo after upgrading to GG 2. The 5-yr RFS rates were 81% for the immediate RP group, 80% for the delayed RP ≤12 mo, and 70% for the delayed RP >12 mo group (univariate log-rank p = 0.03). Cox multivariable regression demonstrated no difference in RFS outcomes between immediate RP for GG 2 disease and delayed RP after upgrading on AS. PPC (hazard ratio [HR] per 10% increment 1.08, 95% confidence interval [CI] 1.02-1.15; p = 0.01) and PSA before RP (HR 1.06, 95% CI 1.03-1.09; p < 0.01) were significantly associated with the risk of recurrence.

CONCLUSIONS AND CLINICAL IMPLICATIONS

PPC and PSA before RP, but not the timing of definitive surgery after upgrade to GG 2, were associated with the risk of PCa recurrence after RP on multivariable analysis. These findings support the safety of AS and delayed definitive therapy for a subset of patients with GG 2 disease.

PATIENT SUMMARY

In a large group of 1259 patients with low-grade prostate cancer, we found that delaying surgical treatment after an initial period of active surveillance resulted in no differences in prostate cancer recurrence. Our results support the safety of active surveillance for low-grade prostate cancer.

Redefining prostate cancer risk stratification: a pioneering strategy to estimate outcome based on Ki67 immunoscoring

Accurate prostate cancer (PCa) patient diagnosis and risk assessment are key to ensure the best outcome. Currently, low- and favorable intermediate-risk PCa patients may be offered AS due to the indolent nature of the disease. Nonetheless, deciding between active surveillance and curative-intent treatment remains an intricate task, as a subset of these patients may eventually progress, enduring poorer prognosis. Herein, we sought to construct risk calculators based on cancer biomarkers, enabling more accurate discrimination among patients which may benefit from active interventions.Ki67 immunoscore, GSTP1 and KLF8 promoter methylation levels (me) were assessed in PCa tissues. Study endpoints included overall and biochemical recurrence-free (BCR) survival. Combination with relevant clinicopathological parameters allowed for construction of graphical calculating tools (nomograms).Higher Ki67 index correlated with worse BCR-free survival, whereas higher KLF8me levels were associated with improved overall survival, especially in patients with lower-grade tumors. GSTP1me levels had no prognostic value. Among prognostic models tested, a BCR-risk calculator - ProstARK (including Ki67 and clinicopathologic parameters) - disclosed 79.17% specificity, 66.67% sensitivity, 55% positive predictive value, 86% negative predictive value, and 75.76% accuracy. Similar results were found using an independent PCa biopsy cohort, validating its prognostication ability.Combining clinicopathologic features and Ki67 index into a risk calculator enables easy and accurate implementation of a novel PCa prognostication tool. This nomogram may be useful for a more accurate selection of patients for active surveillance protocols. Nonetheless, validation in a larger, multicentric, set of diagnostic PCa biopsies is mandatory for further confirmation of these results.

MRI-based prostate cancer classification using 3D efficient capsule network

BACKGROUND

Prostate cancer (PCa) is the most common cancer in men and the second leading cause of male cancer-related death. Gleason score (GS) is the primary driver of PCa risk-stratification and medical decision-making, but can only be assessed at present via biopsy under anesthesia. Magnetic resonance imaging (MRI) is a promising non-invasive method to further characterize PCa, providing additional anatomical and functional information. Meanwhile, the diagnostic power of MRI is limited by qualitative or, at best, semi-quantitative interpretation criteria, leading to inter-reader variability.

PURPOSES

Computer-aided diagnosis employing quantitative MRI analysis has yielded promising results in non-invasive prediction of GS. However, convolutional neural networks (CNNs) do not implicitly impose a frame of reference to the objects. Thus, CNNs do not encode the positional information properly, limiting method robustness against simple image variations such as flipping, scaling, or rotation. Capsule network (CapsNet) has been proposed to address this limitation and achieves promising results in this domain. In this study, we develop a 3D Efficient CapsNet to stratify GS-derived PCa risk using T2-weighted (T2W) MRI images.

METHODS

In our method, we used 3D CNN modules to extract spatial features and primary capsule layers to encode vector features. We then propose to integrate fully-connected capsule layers (FC Caps) to create a deeper hierarchy for PCa grading prediction. FC Caps comprises a secondary capsule layer which routes active primary capsules and a final capsule layer which outputs PCa risk. To account for data imbalance, we propose a novel dynamic weighted margin loss. We evaluate our method on a public PCa T2W MRI dataset from the Cancer Imaging Archive containing data from 976 patients.

RESULTS

Two groups of experiments were performed: (1) we first identified high-risk disease by classifying low + medium risk versus high risk; (2) we then stratified disease in one-versus-one fashion: low versus high risk, medium versus high risk, and low versus medium risk. Five-fold cross validation was performed. Our model achieved an area under receiver operating characteristic curve (AUC) of 0.83 and 0.64 F1-score for low versus high grade, 0.79 AUC and 0.75 F1-score for low + medium versus high grade, 0.75 AUC and 0.69 F1-score for medium versus high grade and 0.59 AUC and 0.57 F1-score for low versus medium grade. Our method outperformed state-of-the-art radiomics-based classification and deep learning methods with the highest metrics for each experiment. Our divide-and-conquer strategy achieved weighted Cohen's Kappa score of 0.41, suggesting moderate agreement with ground truth PCa risks.

CONCLUSIONS

In this study, we proposed a novel 3D Efficient CapsNet for PCa risk stratification and demonstrated its feasibility. This developed tool provided a non-invasive approach to assess PCa risk from T2W MR images, which might have potential to personalize the treatment of PCa and reduce the number of unnecessary biopsies.

Delaying Surgery in Favorable-Risk Prostate Cancer Patients: An NCDB Analysis of Oncologic Outcomes

INTRODUCTION

Concern for overtreatment in very low-, low-, and favorable intermediate-risk prostate cancer has promoted a more conservative approach through active surveillance (AS) with comparable survival outcomes. We analyzed the National Cancer Database (NCDB) to determine if delaying radical prostatectomy greater than 6 months is associated with an increase in the rate of adverse pathology or secondary treatment (adjuvant or salvage) at radical prostatectomy.

METHODS

Utilizing the NCDB from 2004 to 2019, 40 to 75-year-old men with very low-, low-, and favorable-intermediate-risk prostate cancer, as defined by the National Comprehensive Cancer Network, were identified for this study. These individuals received radical prostatectomy either before or after 6 months following diagnosis. Clinical, demographic, and pathologic characteristics were obtained. Adverse pathologic outcomes were defined as pT3-4N0-1 and/or positive surgical margins. Multiple logistic regression models were used to predict delays in treatment, adverse pathologic outcomes, and receipt of secondary therapy. Survival analysis was performed using the Cox Proportional Hazards Model and the Kaplan-Meier Method.

RESULTS

Of the 195,397 patients who met inclusion criteria, only 13,393 patients received surgery 6 months after diagnosis. The median time of delay was 7.5 months compared to 2.3 months in the immediate treatment group. Overall, delaying surgery had no statistically significant impact on adverse pathologic outcomes, regardless of risk category. However, when accounting for the interaction between race and delayed treatment, non-Hispanic black patients who received a delay in treatment were more likely to experience adverse features (OR 1.12, 95%CI 1.00-1.26, P = .041). Conversely, patients who had delayed surgery were less likely to receive additional therapy (either adjuvant or salvage) (OR 0.60, 95%CI 0.52-0.68, P < .001). Survival analysis showed that both groups fared well, with a 5-year survival of 97% for both groups. The treatment group was not predictive of survival.

CONCLUSION

Overall, delaying surgery more than 6 months following diagnosis did not have a significant impact on adverse pathologic features or overall survival. However, when specifically looking at non-Hispanic black patients with a treatment delay, these patients were at increased risk for adverse features, suggesting that the negative impact of treatment delay depends on the patient's race. As race is a social construct, this finding likely points to the complex socioeconomic factors that contribute to overall health outcomes rather than any inherent disease characteristics. Lastly, delayed treatment patients were actually less likely to require secondary therapy, regardless of race, possibly reflecting high clinician acumen in selecting patients appropriate for treatment delay. The results suggest that patients who ultimately "fail" AS and require subsequent surgery have overall comparable survival outcomes. However, pathologic outcomes are dependent on the patient's underlying race, with non-Hispanic black patients experiencing an increased risk of adverse outcomes if treatment is delayed.

The CONFIRM trial protocol: the utility of prostate-specific membrane antigen positron emission tomography/computed tomography in active surveillance for prostate cancer

OBJECTIVES

Primary objectives: To determine the additive value of prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) in the risk stratification of men with newly diagnosed prostate cancer (PCa) who would have otherwise been deemed suitable for active surveillance (AS). Specifically, we aim to determine if PSMA PET/CT can detect a cohort of men on AS that are in fact high risk and likely to experience unfavourable outcomes should they remain on their current treatment pathway.

SECONDARY OBJECTIVES

to determine the additive value of PSMA PET/CT to repeat multiparametric magnetic resonance imaging (mpMRI) of the prostate and explore whether a confirmatory biopsy may be avoided in men with a negative PSMA PET/CT and a negative repeat mpMRI of the prostate (Prostate Imaging-Reporting and Data System score of <3). Furthermore, to develop a nomogram combining clinical, imaging and biomarker data to predict the likelihood of failure on AS in men with high-risk features. Also, a blood sample will be taken to perform a Prostate Health Index test at the time of confirmatory biopsy. Furthermore, a portion of this blood will be stored at a biobank for up to 5 years if a follow-up study on molecular biomarkers and genetic assays in this cohort of men is indicated, based on the results from the CONFIRM trial.

PATIENTS AND METHODS

The CONFIRM trial is a prospective, multicentre, pre-test/post-test, cohort study across Victoria, Australia, involving men with newly diagnosed low-risk PCa with high-risk features, considered suitable for AS and undergoing confirmatory biopsy. The trial's goal is to provide high-quality evidence to establish whether PSMA PET/CT has a role in risk-stratifying men deemed suitable for AS despite having high-risk feature(s).

RESULTS

The CONFIRM trial will measure the proportion of men deemed unsuitable for ongoing AS based on pathological upgrading and multidisciplinary team recommendation due to PSMA PET/CT scan and PSMA-targeted confirmatory biopsy. Additionally, the positive and negative predictive values, sensitivity, and specificity of PSMA PET/CT will be calculated in isolation and combined with repeat mpMRI of the prostate.

CONCLUSIONS

This trial will provide robust prospective data to determine if PSMA-PET/CT and standard of care (prostate biopsy ± repeat mpMRI) can improve diagnostic certainty in men undergoing confirmatory biopsy for low-grade PCa with high-risk features.

Mortality reduction and cumulative excess incidence (CEI) in the prostate-specific antigen (PSA) screening era

The extent to which PSA screening is related to prostate cancer mortality reduction in the United States (US) is controversial. US Surveillance, Epidemiology, and End Results Program (SEER) data from 1980 to 2016 were examined to assess the relationship between prostate cancer mortality and cumulative excess incidence (CEI) in the PSA screening era and to clarify the impact of race on this relationship. CEI was considered as a surrogate for the intensity of prostate cancer screening with PSA testing and subsequent biopsy as appropriate. Data from 163,982,733 person-years diagnosed with 544,058 prostate cancers (9 registries, 9% of US population) were examined. Strong inverse linear relationships were noted between CEI and prostate cancer mortality, and 317,356 prostate cancer deaths were avoided. Eight regions of the US demonstrated prostate cancer mortality reduction of 46.0-63.7%. On a per population basis, the lives of more black men than white men were saved in three of four registries with sufficient black populations for comparison. Factor(s) independent of CEI (potential effects of treatment advances) explained 14.6% of the mortality benefit (p-value = 0.3357) while there was a significant main effect of CEI (effect = -0.0064; CI: [-0.0088, -0.0040]; p-value < 0.0001). Therefore, there is a strong relationship between CEI and prostate cancer mortality reduction that was not related to factors independent of screening utilization. Minority populations have experienced large mortality reductions in the context of PSA mass utilization.

Impact of a negative confirmatory biopsy on risk of disease progression among men on active surveillance for prostate cancer

OBJECTIVE

Most prostate cancer active surveillance (AS) protocols suggest a confirmatory biopsy within 12 to 18 months of diagnosis to mitigate the risk of unsampled high-grade disease. We investigate whether the results of confirmatory biopsy impact AS outcomes and could be used to tailor surveillance intensity.

METHODS

We retrospectively reviewed our institutional database of prostate cancer patients managed by AS from 1997 to 2019 who underwent confirmatory biopsy and ≥3 biopsies overall. Biopsy progression was defined as either an increase in grade group or an increase in the proportion of positive biopsy cores to >34% and was compared between patients with a negative vs positive confirmatory biopsy using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

We identified 452 patients meeting inclusion criteria for this analysis, of whom 169 (37%) had a negative confirmatory biopsy. With a median follow-up of 6.8 years, 37% of patients progressed to treatment, most commonly due to biopsy progression. A negative confirmatory biopsy was significantly associated with biopsy progression-free survival in multivariable analysis (HR 0.54, 95% CI 0.34-0.88, P = 0.013), adjusting for known clinical and pathologic factors, including use of mpMRI prior to confirmatory biopsy. Negative confirmatory biopsy was also associated with an increased risk of adverse pathologic features at prostatectomy but not with biochemical recurrence among men who ultimately underwent definitive treatment.

CONCLUSIONS

A negative confirmatory biopsy is associated with a lower risk of biopsy progression. While the increased risk of adverse pathology at time of definitive treatment sounds a small cautionary note regarding decreasing surveillance intensity, the majority of such patients have a favorable outcome on AS.

Exosome Analysis in Prostate Cancer: How They Can Improve Biomarkers' Performance

Exosomes are extracellular nanovesicles (EV), that is, carriers of different biomolecules such as lipids, proteins, nucleic acids. Their composition and the fact that their release dramatically increases in cases of tumorigenesis open up different scenarios on their possible application to research into new biomarkers. The first purpose of the present review was to specifically analyze and compare different methodologies available for the use of exosomes in prostate cancer (PC). The most widely applied methodologies include ultracentrifugation techniques, size-based techniques, immunoaffinity capture-based techniques (mainly ELISA), and precipitation. To optimize the acquisition of exosomes from the reference sample, more techniques can be applied in sequence for a single extraction, thereby determining an increase in labor time and costs. The second purpose was to describe clinical results obtained with the analysis of PSA-expressing exosomes in PC; this provides an incredibly accurate method of discriminating between healthy patients and those with prostate disease. Specifically, the IC-ELISA alone method achieved 98.57% sensitivity and 80.28% specificity in discriminating prostate cancer (PC) from benign prostatic hyperplasia (BPH). An immunocapture-based ELISA assay was performed to quantify and characterize carbonic anhydrase (CA) IX expression in exosomes. The results revealed that CA IX positive exosomes were 25-fold higher in plasma samples from PC patients than in those from healthy controls. The analysis of PC-linked exosomes represents a promising diagnostic model that can effectively distinguish patients with PC from those with non-malignant prostatic disease. However, the use of exosome analysis in clinical practice is currently limited by several issues, including a lack of standardization in the analytical process and high costs, which are still too high for large-scale use.

Research progress on deep learning in magnetic resonance imaging-based diagnosis and treatment of prostate cancer: a review on the current status and perspectives

Multiparametric magnetic resonance imaging (mpMRI) has emerged as a first-line screening and diagnostic tool for prostate cancer, aiding in treatment selection and noninvasive radiotherapy guidance. However, the manual interpretation of MRI data is challenging and time-consuming, which may impact sensitivity and specificity. With recent technological advances, artificial intelligence (AI) in the form of computer-aided diagnosis (CAD) based on MRI data has been applied to prostate cancer diagnosis and treatment. Among AI techniques, deep learning involving convolutional neural networks contributes to detection, segmentation, scoring, grading, and prognostic evaluation of prostate cancer. CAD systems have automatic operation, rapid processing, and accuracy, incorporating multiple sequences of multiparametric MRI data of the prostate gland into the deep learning model. Thus, they have become a research direction of great interest, especially in smart healthcare. This review highlights the current progress of deep learning technology in MRI-based diagnosis and treatment of prostate cancer. The key elements of deep learning-based MRI image processing in CAD systems and radiotherapy of prostate cancer are briefly described, making it understandable not only for radiologists but also for general physicians without specialized imaging interpretation training. Deep learning technology enables lesion identification, detection, and segmentation, grading and scoring of prostate cancer, and prediction of postoperative recurrence and prognostic outcomes. The diagnostic accuracy of deep learning can be improved by optimizing models and algorithms, expanding medical database resources, and combining multi-omics data and comprehensive analysis of various morphological data. Deep learning has the potential to become the key diagnostic method in prostate cancer diagnosis and treatment in the future.

Implementation of Active Surveillance for Prostate Cancer: A Story of Little Pride and Much Prejudice in the Greek Health Care System

The healthcare system in Greece consists of a mixed public and private sector that contributes to varying extents to the provision of general or specialized health services. Despite intertemporal efforts and investments by the government, the health system remained predominantly underdeveloped in comparison with most European countries. An accurate mirror of the imbalances in cancer care is the underutilization of active surveillance (AS) for prostate cancer. Although AS (a monitoring method to delay or even avoid unnecessary treatment) is becoming the de facto standard of care for low-risk prostate cancer, it remains unpopular in some countries. Focusing on efforts to expand knowledge among the urological community, continuous patient education, and quality improvement of health services will eventually boost national awareness and compliance and promote a radical change of attitude towards AS.

Natural history of incidentally diagnosed prostate cancer after holmium laser enucleation of the prostate

OBJECTIVES

There is no consensus on the management plan for incidental prostate cancer (IPCa) after holmium laser enucleation of the prostate (HoLEP). This study aims to investigate the natural course of this disease and suggest appropriate treatment in real clinical practice.

METHODS

The medical records of a prospective cohort of patients with LUTS/BPH who underwent HoLEP between July 2008 and December 2020 at Seoul National University Hospital were retrospectively reviewed. Patients who underwent HoLEP for palliative purpose of prostate cancer control were excluded. The natural history of IPCa was assessed by the clinician in a descriptive manner for each treatment option.

RESULTS

Among 2630 patients, 141 (5.4%) were diagnosed with IPCa after HoLEP. Pathologic T stage and magnetic resonance imaging results were highly associated with the physician's primary treatment decision-making for IPCa. Active surveillance (AS) was performed in 80% of patients, of whom 90% underwent follow-up without intervention, while the remaining 10% underwent deferred active treatment with a median follow-up of 46.3 months due to International Society of Urological Pathology grade group upgrading or increasing core involvement percentage. Meanwhile, 20% of patients underwent immediate active treatment. With a median follow-up period of 88.3 months after treatment, only one of 25 patients had biochemical recurrence.

CONCLUSIONS

The incidence of IPCa after HoLEP was 5.4%, and among these, approximately 20% proceeded with immediate definitive therapy and an additional 6% ultimately received definitive therapy within a median of 4 years of AS but showed excellent oncological outcomes.

Pilot study for generating and assessing nomograms and decision curves analysis to predict clinically significant prostate cancer using only spatially registered multi-parametric MRI

Background

Current prostate cancer evaluation can be inaccurate and burdensome. To help non-invasive prostate tumor assessment, recent algorithms applied to spatially registered multi-parametric (SRMP) MRI extracted novel clinically relevant metrics, namely the tumor's eccentricity (shape), signal-to-clutter ratio (SCR), and volume.

Purpose

Conduct a pilot study to predict the risk of developing clinically significant prostate cancer using nomograms and employing Decision Curves Analysis (DCA) from the SRMP MRI-based features to help clinicians non-invasively manage prostate cancer.

Methods

This study retrospectively analyzed 25 prostate cancer patients. MP-MRI (T1, T2, diffusion, dynamic contrast-enhanced) were resized, translated, and stitched to form SRMP MRI. Target detection algorithm [adaptive cosine estimator (ACE)] applied to SRMP MRI determines tumor's eccentricity, noise reduced SCR (by regularizing or eliminating principal components (PC) from the covariance matrix), and volume. Pathology assessed wholemount prostatectomy for Gleason score (GS). Tumors with GS >=4+3 (<=3+4) were judged as "Clinically Significant" ("Insignificant"). Logistic regression combined eccentricity, SCR, volume to generate probability distribution. Nomograms, DCA used all patients plus training (13 patients) and test (12 patients) sets. Area Under the Curves for (AUC) for Receiver Operator Curves (ROC) and p-values evaluated the performance.

Results

Combining eccentricity (0.45 ACE threshold), SCR (3, 4 PCs), SCR (regularized, modified regularization) with tumor volume (0.65 ACE threshold) improved AUC (>0.70) for ROC curves and p-values (<0.05) for logistic fit. DCA showed greater net benefit from model fit than univariate analysis, treating "all," or "none." Training/test sets achieved comparable AUC but with higher p-values.

Conclusions

Performance of nomograms and DCA based on metrics derived from SRMP-MRI in this pilot study were comparable to those using prostate serum antigen, age, and PI-RADS.

Prostate Cancer Tumor Volume and Genomic Risk

Background

Despite the historic association of higher prostate cancer volume with worse oncologic outcomes, little is known about the impact of tumor volume on cancer biology.

Objective

To characterize the relationship between tumor volume (measured by percent positive cores [PPC]) and cancer biology (measured by Decipher genomic risk classifier [GC]) in men who underwent prostate biopsy.

Design setting and participants

Prostate biopsies from 52 272 men profiled with Decipher captured in a population-based prospective tumor registry were collected from 2016 to 2021.

Outcome measurements and statistical analysis

The degree of distribution and correlation of PPC with a GC score across grade group (GG) strata were examined using the Mann-Whitney U test, Pearson correlation coefficient, and multivariable linear regression controlled for clinicopathologic characteristics.

Results and limitations

A total of 38 921 (74%) biopsies passed quality control (14 331 GG1, 16 159 GG2, 5661 GG3, 1775 GG4, and 995 GG5). Median PPC and GC increased with sequentially higher GG. There was an increasingly positive correlation (r) between PPC and GC in GG2-5 prostate cancer (r [95% confidence interval {CI}]: 0.07 [0.5, 0.8] in GG2, 0.15 [0.12, 0.17] in GG3, 0.20 [0.15, 0.24] in GG4, and 0.25 [0.19, 0.31] in GG5), with no correlation in GG1 disease (r = 0.01, 95% CI [-0.001, 0.03]). In multivariable linear regression, GC was significantly associated with higher PPC for GG2-5 (all p < 0.05) but was not significantly associated with PPC for GG1. Limitations include retrospective design and a lack of final pathology from radical prostatectomy specimens.

Conclusions

Higher tumor volume was associated with worse GC for GG2-5 prostate cancer, whereas tumor volume was not associated with worse GC for GG1 disease. The finding that tumor volume is not associated with worse cancer biology in GG1 disease encourages active surveillance for most patients irrespective of tumor volume.

Patient summary

We studied the relationship between prostate cancer tumor volume and cancer biology, as measured by the Decipher genomic risk score, in men who underwent prostate biopsy. We found that tumor volume was not associated with worse cancer biology for low-grade prostate cancer. Our findings reassuringly support recent guidelines to recommend active surveillance for grade group 1 prostate cancer in most patients, irrespective of tumor volume.

Feasibility of aspirin and/or vitamin D3 for men with prostate cancer on active surveillance with Prolaris® testing

Objectives

To test the feasibility of a randomised controlled trial (RCT) of aspirin and/or vitamin D3 in active surveillance (AS) low/favourable intermediate risk prostate cancer (PCa) patients with Prolaris® testing.

Patients and Methods

Newly-diagnosed low/favourable intermediate risk PCa patients (PSA ≤ 15 ng/ml, International Society of Urological Pathology (ISUP) Grade Group ≤2, maximum biopsy core length <10 mm, clinical stage ≤cT2c) were recruited into a multi-centre randomised, double-blind, placebo-controlled study (ISRCTN91422391, NCT03103152). Participants were randomised to oral low dose (100 mg), standard dose (300 mg) aspirin or placebo and/or vitamin D3 (4000 IU) versus placebo in a 3 × 2 factorial RCT design with biopsy tissue Prolaris® testing. The primary endpoint was trial acceptance/entry rates. Secondary endpoints included feasibility of Prolaris® testing, 12-month disease re-assessment (imaging/biochemical/histological), and 12-month treatment adherence/safety. Disease progression was defined as any of the following (i) 50% increase in baseline PSA, (ii) new Prostate Imaging-Reporting and Data System (PI-RADS) 4/5 lesion(s) on multi-parametric MRI where no previous lesion, (iii) 33% volume increase in lesion size, or radiological upstaging to ≥T3, (iv) ISUP Grade Group upgrade or (v) 50% increase in maximum cancer core length.

Results

Of 130 eligible patients, 104 (80%) accepted recruitment from seven sites over 12 months, of which 94 patients represented the per protocol population receiving treatment. Prolaris® testing was performed on 76/94 (81%) diagnostic biopsies. Twelve-month disease progression rate was 43.3%. Assessable 12-month treatment adherence in non-progressing patients to aspirin and vitamin D across all treatment arms was 91%. Two drug-attributable serious adverse events in 1 patient allocated to aspirin were identified. The study was not designed to determine differences between treatment arms.

Conclusion

Recruitment of AS PCa patients into a multi-centre multi-arm placebo-controlled RCT of minimally-toxic adjunctive oral drug treatments with molecular biomarker profiling is acceptable and safe. A larger phase III study is needed to determine optimal agents, intervention efficacy, and outcome-associated biomarkers.

Diet and Health-related Quality of Life Among Men on Active Surveillance for Early-stage Prostate Cancer: The Men's Eating and Living Study (Cancer and Leukemia Group 70807 [Alliance])

BACKGROUND

Health-related quality of life (HRQoL) among patients with localized prostate cancer (PC) on active surveillance (AS) and whether it may be improved through lifestyle-focused interventions remain underdefined.

OBJECTIVE

To assess longitudinal changes in HRQoL in patients who received and those who did not receive a behavioral intervention that increased vegetable intake.

DESIGN, SETTING, AND PARTICIPANTS

A secondary analysis of participants in the Men's Eating and Living (MEAL) study (Cancer and Leukemia Group 70807 [Alliance]), a randomized trial of vegetable consumption in patients on AS, was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Patient-reported outcomes (PROs) included the Memorial Anxiety Scale for Prostate Cancer (MAX-PC), the Expanded Prostate Cancer Index Composite 26 (EPIC-26), and the Functional Assessment of Cancer Therapy Scale-Prostate (FACT-P). Areas under the curves (AUCs) were used to summarize serial HRQoL.

RESULTS AND LIMITATIONS

PROs were completed in 87% (n = 387) of the intention-to-collect population. Baseline characteristics of patients completing HRQoL measures did not differ significantly from the entire study population or between groups. Baseline scores were high for all PROs and remained stable over 24 mo, with no significant differences from baseline at any time point. In adjusted analyses, there were no significant differences in summary AUC measures comparing control with intervention for the total MAX-PC score (p = 0.173); EPIC-26 domains of urinary incontinence (p = 0.210), urinary obstruction (p = 0.062), bowel health (p = 0.607), sexual health (p = 0.398), and vitality (p = 0.363); and total FACT-P scores (p = 0.471).

CONCLUSIONS

Among men with localized PC on AS enrolled in a randomized trial, HRQoL was high across multiple domains at baseline, remained high during follow-up, and did not change in response to a behavioral intervention that increased vegetable intake.

PATIENT SUMMARY

Patients with localized prostate cancer enrolled on active surveillance experience minimal cancer-associated anxiety, suffer low levels of cancer-associated symptoms, and perceive high physical and emotional well-being.

Using Competing Risk of Mortality to Inform the Transition from Prostate Cancer Active Surveillance to Watchful Waiting

BACKGROUND

For men on active surveillance (AS) for prostate cancer (PCa), disease progression and age-related changes in health may influence decisions about pursuing curative treatment.

OBJECTIVE

To evaluate the predicted PCa and non-PCa mortality at the time of reclassification among men on AS, to identify clinical criteria for considering a transition from AS to watchful waiting (WW).

DESIGN, SETTING, AND PARTICIPANTS

Patients enrolled in a large AS program who experienced biopsy grade reclassification (Gleason grade increase) were retrospectively examined. All patients who had complete documentation of medical comorbidities at reclassification were included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A validated model was used to assess 10- and 15-yr untreated PCa and non-PCa mortalities based on patient comorbidities and PCa clinical characteristics. We compared the ratio of predicted PCa mortality with predicted non-PCa mortality ("predicted mortality ratio") and divided patients into four risk tiers based on this ratio: (1) tier 1 (ratio: >0.33), (2) tier 2 (ratio 0.33-0.20), (3) tier 3 (ratio 0.20-0.10), and (4) tier 4 (ratio <0.10).

RESULTS AND LIMITATIONS

Of the 344 men who were reclassified, 98 (28%) were in risk tier 1, 85 (25%) in tier 2, 93 (27%) in tier 3, and 68 (20%) in tier 4 for 10-yr mortality. Fifteen-year risk tiers were distributed similarly. The 23 (6.7%) men who met the "transition triad" (age >75 yr, Charlson Comorbidity Index >3, and grade group ≤2) had a 14-fold higher non-PCa mortality risk and a lower predicted mortality ratio than those who did not (0.07 vs 0.23, p < 0.001). The primary limitations of our study included its retrospective nature and the use of predicted mortalities.

CONCLUSIONS

At reclassification, nearly half of patients had a more than five-fold and one in five patients had a more than ten-fold higher risk of non-PCa death than patients having a risk of untreated PCa death. Despite a more significant cancer diagnosis, a transition to WW for older men with multiple comorbidities and grade group <3 PCa should be considered.

PATIENT SUMMARY

Men with favorable-risk prostate cancer and life expectancy of >10 yr are often enrolled in active surveillance, which entails delay of curative treatment until there is evidence of more aggressive disease. We examined a group of men on active surveillance who developed more aggressive disease, and found, nevertheless, that the majority of these men continued to have a dramatically higher risk of death from non-prostate cancer causes than from prostate cancer based on a risk prediction tool. For men older than 75 yr, who have multiple medical conditions and who do not have higher-grade cancer, it may be reasonable to reconsider the need for curative treatment given the low risk of death from prostate cancer compared with the risk of death from other causes.

Clinical Utility of Prostate Health Index for Diagnosis of Prostate Cancer in Patients with PI-RADS 3 Lesions

The risk of prostate cancer (PCa) in prostate imaging reporting and data system version 2 (PI-RADSv2) score-3 lesions is equivocal; it is regarded as an intermediate status of presented PCa. In this study, we evaluated the clinical utility of the prostate health index (PHI) for the diagnosis of PCa and clinically significant PCa (csPCa) in patients with PI-RADSv2 score-3 lesions. The study cohort included patients who underwent a transrectal ultrasound (TRUS)-guided, cognitive-targeted biopsy for PI-RADSv2 score-3 lesions between November 2018 and April 2021. Before prostate biopsy, the prostate-specific antigen (PSA) derivatives, such as total PSA (tPSA), [-2] proPSA (p2PSA) and free PSA (fPSA) were determined. The calculation equation of PHI is as follows: [(p2PSA/fPSA) × tPSA ½]. Using a receiver operating characteristic (ROC) curve analysis, the values of PSA derivatives measured by the area under the ROC curve (AUC) were compared. For this study, csPCa was defined as Gleason grade 2 or higher. Of the 392 patients with PI-RADSv2 score-3 lesions, PCa was confirmed in 121 (30.9%) patients, including 59 (15.1%) confirmed to have csPCa. Of all the PSA derivatives, PHI and PSA density (PSAD) showed better performance in predicting overall PCa and csPCa, compared with PSA (all p < 0.05). The AUC of the PHI for predicting overall PCa and csPCa were 0.807 (95% confidence interval (CI): 0.710−0.906, p = 0.001) and 0.819 (95% CI: 0.723−0.922, p < 0.001), respectively. By the threshold of 30, PHI was 91.7% sensitive and 46.1% specific for overall PCa, and was 100% sensitive for csPCa. Using 30 as a threshold for PHI, 34.4% of unnecessary biopsies could have been avoided, at the cost of 8.3% of overall PCa, but would include all csPCa.

Rapid Histological Assessment of Prostate Specimens in the Three-dimensional Space by Hydrophilic Tissue Clearing and Confocal Microscopy

Microscopic examination of biopsied and resected prostatic specimens is the mainstay in the diagnosis of prostate cancer. However, conventional analysis of hematoxylin and eosin (H&E)-stained tissue is time-consuming and offers limited two-dimensional (2D) information. In the current study, we devised a method-termed Prostate Rapid Optical examination for cancer STATus (proSTAT)-for rapid screening of prostate cancer using high-resolution 2D and three-dimensional (3D) confocal images obtained after hydrophilic tissue clearing of 100-µm-thick tissue slices. The results of the proSTAT method were compared with those of traditional H&E stains for the analysis of cores (n=15) obtained from radical prostatectomy specimens (n=5). Gland lumen formation, consistent with Gleason pattern 3, was evident following tracking of multiple optical imaging sections. In addition, 3D rendering allowed visualizing a tubular network of interconnecting branches. Rapid 3D fluorescent labeling of tumor protein p63 accurately distinguished prostate adenocarcinoma from normal tissue and benign lesions. Compared with conventional stains, the 3D spatial and molecular information extracted from proSTAT may significantly increase the amount of available data for pathological assessment of prostate specimens. Our approach is amenable to automation and-subject to independent validation-can find a wide spectrum of clinical and research applications.

Potential of the Stromal Matricellular Protein Periostin as a Biomarker to Improve Risk Assessment in Prostate Cancer

Prostate cancer (PCa) ranges from indolent to aggressive tumors that may rapidly progress and metastasize. The switch to aggressive PCa is fostered by reactive stroma infiltrating tumor foci. Therefore, reactive stroma-based biomarkers may potentially improve the early detection of aggressive PCa, ameliorating disease classification. Gene expression profiles of PCa reactive fibroblasts highlighted the up-regulation of genes related to stroma deposition, including periostin and sparc. Here, the potential of periostin as a stromal biomarker has been investigated on PCa prostatectomies by immunohistochemistry. Moreover, circulating levels of periostin and sparc have been assessed in a low-risk PCa patient cohort enrolled in active surveillance (AS) by ELISA. We found that periostin is mainly expressed in the peritumoral stroma of prostatectomies, and its stromal expression correlates with PCa grade and aggressive disease features, such as the cribriform growth. Moreover, stromal periostin staining is associated with a shorter biochemical recurrence-free survival of PCa patients. Interestingly, the integration of periostin and sparc circulating levels into a model based on standard clinico-pathological variables improves its performance in predicting disease reclassification of AS patients. In this study, we provide the first evidence that circulating molecular biomarkers of PCa stroma may refine risk assessment and predict the reclassification of AS patients.

Combining and analyzing novel multi-parametric magnetic resonance imaging metrics for predicting Gleason score

BACKGROUND

Radiologists currently subjectively examine multi-parametric magnetic resonance imaging (MP-MRI) to determine prostate tumor aggressiveness using the Prostate Imaging Reporting and Data System scoring system (PI-RADS). Recent studies showed that modified signal to clutter ratio (SCR), tumor volume, and eccentricity (elongation or roundness) of prostate tumors correlated with Gleason score (GS). No previous studies have combined the prostate tumor's shape, SCR, tumor volume, in order to predict potential tumor aggressiveness and GS.

METHODS

MP-MRI (T1, T2, diffusion, dynamic contrast-enhanced images) were obtained, resized, translated, and stitched to form spatially registered multi-parametric cubes. Multi-parametric signatures that characterize prostate tumors were inserted into a target detection algorithm [adaptive cosine estimator (ACE)]. Pixel-based blobbing, and labeling were applied to the threshold ACE images. Eccentricity calculation used moments of inertia from the blobs. Tumor volume was computed by counting pixels within multi parametric MRI blobs and tumor outlines based on pathologist assessment of whole mount histology. Pathology assessment of GS was performed on whole mount prostatectomy. The covariance matrix and mean of normal tissue background was computed from normal prostate. Using signatures and normal tissue statistics, the z-score, noise corrected SCR [principal component (PC), modified regularization] from each patient was computed. Eccentricity, tumor volume, and SCR were fitted to GS. Analysis of variance assesses the relationship among the variables.

RESULTS

A multivariate analysis generated correlation coefficient (0.60 to 0.784) and P value (0.00741 to <0.0001) from fitting two sets of independent variates, namely, tumor eccentricity (the eccentricity for the largest blob, weighted average for the eccentricity) and SCR (removing 3 PCs, removing 4 PCs, modified regularization, and z-score) to GS. The eccentricity t-statistic exceeded the SCR t-statistic. The three-variable fit to GS using tumor volume (histology, MRI) yielded correlation coefficients ranging from 0.724 to 0.819 (P value <<0.05). Tumor volumes generated from histology yielded higher correlation coefficients than MRI volumes. Adding volume to eccentricity and SCR adds little improvement for fitting GS due to higher correlation coefficients among independent variables and little additional, independent information.

CONCLUSIONS

Combining prostate tumors eccentricity with SCR relatively highly correlates with GS.

Active surveillance protocol in prostate cancer in Portugal

OBJECTIVE

To examine clinical practice patterns in locally managing patients under an active surveillance protocol among Portuguese urologists.

INTRODUCTION

Prostate cancer (PCa) is a heterogeneous disease with many prostate adenocarcinomas being indolent and a low probability of ever causing symptoms or death. Active surveillance (AS) is a form of conservative management aimed to reduce over-treatment for low-risk PCa patients. Over the years, experience with AS has grown considerably and is now standard in some countries, however a universal protocol still does not exist.

METHODS

Nationwide anonymous e-survey concerning habits and practices on AS among Portuguese urologists, that consisted of twelve questions and was sent electronically to all 368 current members of the Portuguese Urological Association.

RESULTS

56 urologists were surveyed (15.21% answer rate), evenly distributed geographically and allocated according to years of experience as well as number of PCa patients managed monthly. The vast majority of respondents recommends AS to their patients, particularly ISUP grade 1 patients, whose PSA serum level is bellow 20 ng/mL. Observance of AS programs by patients was not in question but concerns exist over psychological morbidity while harboring disease. Majority believed that international guidelines surveillance protocols were adequate and sufficient, but there are some constraints concerning availability of periodic MRIs and re-biopsy needs.

CONCLUSIONS

AS seems to be sustained in urologist clinical practice, although patients still lag to adhere and choose for active treatment. AS may not be an easy choice for patients and clinicians due to uncertainty of disease progression, risk of loss to follow-up and repeated biopsies but is also a cause for anxiety, depression, uncertainty and a perception of danger.

Construction and validation of N6-methyladenosine long non-coding RNAs signature of prognostic value for early biochemical recurrence of prostate cancer

PURPOSE

Early biochemical recurrence (eBCR) indicated a high risk for potential recurrence and metastasis in prostate cancer. The N6-methyladenosine (m6A) methylation modification played an important role in prostate cancer progression. This study aimed to develop a m6A lncRNA signature to accurately predict eBCR in prostate cancer.

METHODS

Pearson correlation analysis was first conducted to explore m6A lncRNAs and univariate Cox regression analysis was further performed to identify m6A lncRNAs of prognostic roles for predicting eBCR in prostate cancer. The m6A lncRNA signature was constructed by least absolute shrinkage and selection operator analysis (LASSO) in training cohort and further validated in test cohort. Furthermore, half maximal inhibitory concentration (IC50) values were utilized to explore potential effective drugs for high-risk group in this study.

RESULTS

Five hundred and thirty-eighth m6A lncRNAs were searched out through Pearson correlation analysis and 25 out of 538 m6A lncRNAs were identified to pose prediction roles for eBCR in prostate cancers. An m6A lncRNA signature including 5 lncRNAs was successfully built in training cohort. The high-risk group derived from m6A lncRNA signature could efficiently predict eBCR occurrence in both training (p < 0.001) and test cohort (p = 0.002). ROC analysis also confirmed that lncRNA signature in this study posed more accurate prediction roles for eBCR occurrence when compared with PSA, TNM stages and Gleason scores. Drug sensitivity analysis further discovered that various drugs could be potentially utilized to treat high-risk samples in this study.

CONCLUSIONS

The m6A lncRNA signature in this study could be utilized to efficiently predict eBCR occurrence, various clinical characteristic and immune microenvironment for prostate cancer.

Metastatic Potential of Small Testicular Germ Cell Tumors: Implications for Surveillance of Small Testicular Masses

Patient summary

A Feasibility Study of the Therapeutic Response and Durability of Short-term Androgen-targeted Therapy in Early Prostate Cancer Managed with Surveillance: The Therapeutics in Active Prostate Surveillance (TAPS01) Study

Background

Active surveillance (AS) is a preferred management option for men with prostate cancer with favourable prognosis. However, nearly half of men on AS switch to treatment within 5 years, so therapeutic strategies to prevent or delay disease progression could be considered. The androgen receptor is the pre-eminent oncogenic driver in prostate cancer.

Objective

To explore image-based tumour responses and the patient impact of short-duration androgen-targeted therapy (ATT) to abrogate disease progression during AS.

Design, setting, and participants

Men on AS with Cambridge Prognostic Group 1 & 2 (low and favourable intermediate risk) prostate cancer and lesions visible on magnetic resonance imaging (MRI) were recruited to an open-label, single-centre, phase 2 feasibility study of short-term ATT (the TAPS01 study).

Intervention

Apalutamide 240 mg was administered for 90 days.

Outcome measurements and statistical analysis

MRI-measured tumour volume (TV), gland volume (GV), and the TV/GV ratio were calculated at baseline, at day 90 (end of treatment), and at 6- and 18-month follow-up. Quality of life metrics were measured at day 0, day 90, and 6 weeks after ATT.

Results and limitations

Eleven patients (40% of eligible men approached) agreed to participate, of whom nine completed treatment. At day 90, the median percentage reduction was −38.2% (range −51.8% to −23.5%) for GV, −54.2% (range −74.1% to −13.8%) for TV, and −27.2% (range −61.5% to −7.5%) for TV/GV (all p < 0.0001). At 6 mo, while GV had returned to baseline (p = 0.95) both TV (−31.9%; p = 0.0007) and TV/GV (−28.7%; p = 0.0009) remained significantly reduced. This reduction was sustained at 18 months (TV −18%, TV/GV −23.8%; p = 0.01). European Organization for Research and Treatment of Cancer QoL core 30-item questionnaire scores for global, physical, role, and social functioning decreased during treatment, but all were recovering by 6 weeks. EQ-VAS scores were unchanged compared to baseline.

Conclusions

TAPS01 has demonstrated feasibility and patient tolerability for short-term ATT in men on AS. Our data suggest a selective and durable antitumour effect in the short term and support a larger-scale randomised trial.

Patient summary

We investigated the feasibility of short-term treatment with an androgen inhibitor to prevent or delay disease progression for men on active surveillance for prostate cancer. Results for a small group of patients show that 90-day treatment led to a sustained decrease in tumour volume over 18 months. The findings warrant a larger clinical trial for this approach, which could allow patients to delay or even avoid longer-term active treatments.

Risk subtyping and prognostic assessment of prostate cancer based on consensus genes

Prostate cancer (PCa) is the most frequent malignancy in male urogenital system around worldwide. We performed molecular subtyping and prognostic assessment based on consensus genes in patients with PCa. Five cohorts containing 1,046 PCa patients with RNA expression profiles and recorded clinical follow-up information were included. Univariate, multivariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) Cox regression were used to select prognostic genes and establish the signature. Immunohistochemistry staining, cell proliferation, migration and invasion assays were used to assess the biological functions of key genes. Thirty-nine intersecting consensus prognostic genes from five independent cohorts were identified. Subsequently, an eleven-consensus-gene classifier was established. In addition, multivariate Cox regression analyses showed that the classifier served as an independent indicator of recurrence-free survival in three of the five cohorts. Combined receiver operating characteristic (ROC) analysis achieved synthesized effects by combining the classifier with clinicopathological features in four of five cohorts. SRD5A2 inhibits cell proliferation, while ITGA11 promotes cell migration and invasion, possibly through the PI3K/AKT signaling pathway. To conclude, we established and validated an eleven-consensus-gene classifier, which may add prognostic value to the currently available staging system.

By analysis of gene expression profiles of prostate cancer patients from multiple platforms, an eleven-consensus-gene classifier is constructed to provide a robust tool for the prediction of recurrence-free survival.

Diagnostic Accuracy of Contemporary Selection Criteria in Prostate Cancer Patients Eligible for Active Surveillance: A Bayesian Network Meta-Analysis

Background

Several active surveillance (AS) criteria have been established to screen insignificant prostate cancer (insigPCa, defined as organ confined, low grade and small volume tumors confirmed by postoperative pathology). However, their comparative diagnostic performance varies. The aim of this study was to compare the diagnostic accuracy of contemporary AS criteria and validate the absolute diagnostic odds ratio (DOR) of optimal AS criteria.

Methods

First, we searched Pubmed and performed a Bayesian network meta-analysis (NMA) to compare the diagnostic accuracy of contemporary AS criteria and obtained a relative ranking. Then, we searched Pubmed again to perform another meta-analysis to validate the absolute DOR of the top-ranked AS criteria derived from the NMA with two endpoints: insigPCa and favorable disease (defined as organ confined, low grade tumors). Subgroup and meta-regression analyses were conducted to identify any potential heterogeneity in the results. Publication bias was evaluated.

Results

Seven eligible retrospective studies with 3,336 participants were identified for the NMA. The diagnostic accuracy of AS criteria ranked from best to worst, was as follows: Epstein Criteria (EC), Yonsei criteria, Prostate Cancer Research International: Active Surveillance (PRIAS), University of Miami (UM), University of California-San Francisco (UCSF), Memorial Sloan-Kettering Cancer Center (MSKCC), and University of Toronto (UT). I² = 50.5%, and sensitivity analysis with different insigPCa definitions supported the robustness of the results. In the subsequent meta-analysis of DOR of EC, insigPCa and favorable disease were identified as endpoints in ten and twenty-two studies, respectively. The pooled DOR for insigPCa and favorable disease were 0.44 (95%CI, 0.31–0.58) and 0.66 (95%CI, 0.61–0.71), respectively. According to a subgroup analysis, the DOR for favorable disease was significantly higher in US institutions than that in other regions. No significant heterogeneity or evidence of publication bias was identified.

Conclusions

Among the seven AS criteria evaluated in this study, EC was optimal for positively identifying insigPCa patients. The pooled diagnostic accuracy of EC was 0.44 for insigPCa and 0.66 when a more liberal endpoint, favorable disease, was used.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], PROSPERO [CRD42020157048].

Two Decades of Active Surveillance for Prostate Cancer in a Single-Center Cohort: Favorable Outcomes after Transurethral Resection of the Prostate

OBJECTIVE

To report the outcomes of active surveillance (AS) for low-risk prostate cancer (PCa) in a single-center cohort.

PATIENTS AND METHODS

This is a prospective, single-center, observational study. The cohort included all patients who underwent AS for PCa between December 1999 and December 2020 at our institution. Follow-up appointments (FU) ended in February 2021.

RESULTS

A total of 413 men were enrolled in the study, and 391 had at least one FU. Of those who followed up, 267 had PCa diagnosed by transrectal ultrasound (TRUS)-guided biopsy (T1c: 68.3%), while 124 were diagnosed after transurethral resection of the prostate (TURP) (T1a/b: 31.7%). Median FU was 46 months (IQR 25-90). Cancer specific survival was 99.7% and overall survival was 92.3%. Median reclassification time was 11.2 years. After 20 years, 25% of patients were reclassified within 4.58 years, 6.6% opted to switch to watchful waiting, 4.1% died, 17.4% were lost to FU, and 46.8% remained on AS. Those diagnosed by TRUS had a significantly higher reclassification rate than those diagnosed by TURP (p < 0.0001). Men diagnosed by targeted MRI/TRUS fusion biopsy tended to have a higher reclassification probability than those diagnosed by conventional template biopsies (p = 0.083).

CONCLUSIONS

Our single-center cohort spanning over two decades revealed that AS remains a safe option for low-risk PCa even in the long term. Approximately half of AS enrollees will eventually require definitive treatment due to disease progression. Men with incidental prostate cancer were significantly less likely to have disease progression.

LINC01207 promotes prostate cancer progression by sponging miR-1182 to upregulate AKT3

Prostate cancer (PC) is recognized as a common malignancy in male patients. Long non-coding RNA (lncRNA) has been implicated in the development of PC. Recently, long intergenic non-protein coding RNA 1207 (LINC01207) has been reported to regulate the carcinogenesis of multiple cancer types. However, its role in the progression of PC remains to be determined. The aim of the present study was to investigate the expression profile, clinicopathological implication and molecular mechanism of action of LINC01207 in the progression of PC. LINC01207 expression levels were compared between PC tumor and paired normal tissue samples from The Cancer Genome Atlas. The expression of LINC01207 was further analyzed in PC cell lines and a normal prostatic cell line. The role of LINC01207 in proliferation, migration and invasion of PC cells was examined using small interfering RNA-mediated silencing. Western blot analysis was used to investigate the changes in protein levels underlying the mechanism of action of LINC01207. The role of LINC01207 in tumorigenesis was evaluated in a xenograft model. LINC01207 was upregulated in PC tumor samples from TCGA data compared with paired normal tissue. LINC01207 expression was significantly increased in PC cells and tumor tissues compared with in normal prostate cells (RWPE1) and normal prostate tissues, respectively. Furthermore, LINC01207 silencing inhibited PC cell proliferation and colony formation and induced apoptosis. Mechanistic experiments showed that LINC01207 promoted carcinogenesis by sponging miR-1182 to regulate the protein levels of AKT3 in PC cell lines. Thus, the findings of the present study indicated that LINC01207 might play a role in the tumorigenesis of PC and may serve as a therapeutic target for PC treatment.

Evaluation of multiparametric prostate magnetic resonance imaging findings in patients with a Gleason score of 6 in transrectal ultrasonography-guided biopsy

Purpose

We aimed to evaluate prostate multiparametric magnetic resonance imaging (mpMRI) findings of patients with a Gleason score (GS) of 6 and effectiveness of MRI based on the final pathology result in patients undergoing radical prostatectomy (RP).

Material and methods

mpMRI findings of 80 patients who had a GS of 3 + 3 and who underwent mpMRI were evaluated retrospectively. The mpMRI were scored according to the PIRADS v2.1 guidelines. The patients were divided into those with a high probability of clinically significant cancer (CSC) (PI-RADS 4-5) and those with a low probability of CSC (PI-RADS 2-3).

Results

Of the 80 patients, 33.8% had PI-RADS 2-3, and 66.2% had PI-RADS 4-5 lesions. There was a significant difference between the groups in prostate specific antigen (PSA) value, PSA density, patient age, and tumour percentage on biopsy. When the pathology results were taken as the gold standard in the group that underwent RP, sensitivity, specificity, and accuracy of mpMRI were calculated as 94.74%, 100%, and 96.3%, respectively, an increase in the final GS was found in 9 (33.3%) of the 27 patients, and 70.35% of patients were identified as having CSC.

Conclusions

PI-RADS 4-5 scores have high sensitivity and negative predictive value in the diagnosis of CSC. mpMRI is a reliable and non-invasive diagnostic method that can complement biopsy results in decision-making in patients who are initially evaluated as low risk.

Mixed-Beam Approach for High-Risk Prostate Cancer Carbon-Ion Boost Followed by Photon Intensity-Modulated Radiotherapy: Preliminary Results of Phase II Trial AIRC-IG-14300

Purpose

This study represents a descriptive analysis of preliminary results of a Phase II trial on a novel mixed beam radiotherapy (RT) approach, consisting of carbon ions RT (CIRT) followed by intensity-modulated photon RT, in combination with hormonal therapy, for high-risk prostate cancer (HR PCa) with a special focus on acute toxicity.

Methods

Primary endpoint was the evaluation of safety in terms of acute toxicity. Secondary endpoints were early and long-term tolerability of treatment, quality of life (QoL), and efficacy. Data on acute and late toxicities were collected according to RTOG/EORTC. QoL of enrolled patients was assessed by IPSS, EORTC QLQ-C30, EORTC QLQ-PR25, and sexual activity by IIEF-5.

Results

Twenty-six patients were enrolled in the study, but only 15 completed so far the RT course and were included. Immediately after CIRT, no patients experienced GI/GU toxicity. At 1 and 3 months from the whole course RT completion, no GI/GU toxicities greater than grade 2 were observed. QoL scores were overall satisfactory.

Conclusions

The feasibility of the proposed mixed treatment schedule was assessed, and an excellent acute toxicity profile was recorded. Such findings instil confidence in the continuation of this mixed approach, with evaluation of long-term tolerability and efficacy.

Description of Surgical Technique and Oncologic and Functional Outcomes of the Precision Prostatectomy Procedure (IDEAL Stage 1-2b Study)

BACKGROUND

The existing treatment options for men with intermediate- or high-volume low-risk prostate cancer (PCa) are associated with a substantial risk of over- or undertreatment. The development of risk-adjusted therapies is an unmet need for these patients.

OBJECTIVE

To describe our novel technique of precision prostatectomy, a form of surgical focal therapy that allows radical excision of the index PCa lesion along with >90% prostatic tissue extirpation while preserving the prostatic capsule and seminal vesicle/vas deferens complex on the side contralateral to the dominant cancer lesion, and to report on medium-term functional and oncologic outcomes in the first 88 consecutive men who underwent this procedure between December 2016 and January 2020.

DESIGN, SETTING, AND PARTICIPANTS

Men with (1) prostate-specific antigen (PSA) ≤20 ng/ml, (2) clinical T stage ≤cT2, (3) a dominant unilateral lesion with Gleason ≤ 4 + 3 disease with any number or percentage of cores involved ipsilaterally on prostate biopsy, (4) no primary Gleason ≥4 lesion contralaterally, and (5) a preoperative Sexual Health Inventory of Men (SHIM) score of ≥17 (out of 25) with/without phosphodiesterase type-5 inhibitor use who consented to undergo precision prostatectomy were included in this single-arm, single-center, IDEAL stage 2b prospective development study.

INTERVENTION

Robotic precision prostatectomy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The safety and urinary, sexual, and oncologic outcomes of the precision prostatectomy technique were studied. Descriptive statistics and Kaplan-Meier analyses were used to assess 12-mo urinary continence (0-1 pad), 12-mo sexual potency (SHIM score ≥17), 36-mo freedom from clinically significant PCa (grade group ≥2), secondary treatments, metastatic disease, and mortality.

RESULTS AND LIMITATIONS

At study entry, the median age, PSA, and SHIM score were 60.0 yr (interquartile range [IQR] 54.2-65.9), 5.7 ng/ml (IQR 4.2-7.1), and 22 points (IQR 19-24), respectively. The median follow-up was 25 mo (IQR 14-38). At 12 mo, all patients were continent (0-1 pads), with 90.9% of patients using 0 pads. The median time to urinary continence was 1 mo (IQR 1-4). At 12 mo, 85% of all-comers and 90.2% of the preoperatively potent men were potent. The median time to sexual potency was 4 mo (IQR 4-12). From an oncologic standpoint, at 36 mo an estimated 93.4% of the patients were free from clinically significant residual PCa and 91.7% had not undergone any additional treatment. All patients were alive and free of metastatic disease at 36 mo.

CONCLUSIONS

Precision prostatectomy is technically safe and reproducible and offers excellent postoperative functional results. At 36-mo follow-up, the oncologic outcomes and secondary treatment rates appear to be superior to existing ablative focal therapy results. Pending long-term data, a risk-stratified surgical approach to PCa may avoid whole-gland therapy and preserve functional quality of life in men with localized PCa.

PATIENT SUMMARY

Precision prostatectomy is a new form of focal therapy for intermediate-risk prostate cancer in which a 5-10-mm rim of prostate capsule is left on the opposite side of the gland to where the dominant cancer is located. The technique appears to be safe and efficacious and adds to the growing armamentarium of risk-adapted therapies for treatment of localized prostate cancer that avoid the adverse effects on urinary and erectile function of whole-gland treatments.

A Prostate Cancer Proteomics Database for SWATH-MS Based Protein Quantification

Simple Summary

Prostate cancer is the third most frequent cancer in men worldwide, with a notable increase in prevalence over the past two decades. The PSA is the only well-established protein biomarker for prostate cancer diagnosis, staging, and surveillance. It frequently leads to inaccurate diagnosis and overtreatment since it is an organ-specific biomarker rather than a tumour-specific biomarker. As a result, one of the primary goals of prostate cancer proteome research is to identify novel biomarkers that can be used with or instead of PSA, particularly in non-invasive blood samples. Thousands of peptides or assays were detected in blood samples from patients with low- to high-grade prostate cancer and healthy individuals, allowing data processing of sequential window acquisition of all theoretical mass spectra (SWATH-MS). By assisting in the detection of prostate cancer biomarkers in blood samples, this useful resource will improve our understanding of the role of proteomics in prostate cancer diagnosis and risk assessment.

Abstract

Prostate cancer is the most frequent form of cancer in men, accounting for more than one-third of all cases. Current screening techniques, such as PSA testing used in conjunction with routine procedures, lead to unnecessary biopsies and the discovery of low-risk tumours, resulting in overdiagnosis. SWATH-MS is a well-established data-independent (DI) method requiring prior knowledge of targeted peptides to obtain valuable information from SWATH maps. In response to the growing need to identify and characterise protein biomarkers for prostate cancer, this study explored a spectrum source for targeted proteome analysis of blood samples. We created a comprehensive prostate cancer serum spectral library by combining data-dependent acquisition (DDA) MS raw files from 504 patients with low, intermediate, or high-grade prostate cancer and healthy controls, as well as 304 prostate cancer-related protein in silico assays. The spectral library contains 114,684 transitions, which equates to 18,479 peptides translated into 1227 proteins. The robustness and accuracy of the spectral library were assessed to boost confidence in the identification and quantification of prostate cancer-related proteins across an independent cohort, resulting in the identification of 404 proteins. This unique database can facilitate researchers to investigate prostate cancer protein biomarkers in blood samples. In the real-world use of the spectrum library for biomarker detection, using a signature of 17 proteins, a clear distinction between the validation cohort’s pre- and post-treatment groups was observed. Data are available via ProteomeXchange with identifier PXD028651.

Oncological and Functional Outcomes of Patients Undergoing Individualized Partial Gland Cryoablation of the Prostate: A Single-Institution Experience

Objectives: We aim at reporting the functional and oncological outcomes in men with localized prostate cancer who underwent individualized partial gland cryoablation of the prostate by using validated quality-of-life instruments. Methods: We retrospectively reviewed our cryosurgery database between July 2003 and September 2019 for men who were treated with individualized partial gland cryoablation of the prostate at our tertiary care center. Baseline and periodic urinary and sexual function surveys were administered throughout the post-treatment period. Results: A total of 82 men were included in the study. Median follow-up was 28 months (interquartile range: 10.5-59.3 months). A total of 71 men underwent primary individualized partial gland cryoablation, whereas 11 men underwent salvage partial gland ablation. Failure-free survival at 1 to 5 years was 98%, 89%, 84%, 75%, and 75% in the primary therapy group, and 100%, 80%, and 40% in the salvage group at 1 to 3 years, respectively. In the primary therapy group, all 71 patients remained free of pads at 3 months and throughout the follow-up period. Men who had undergone primary focal cryoablation had a higher post-treatment International Index of Erectile Function (IIEF) score, followed by men treated with primary hemi-cryoablation and primary subtotal cryoablation. The American Urological Association (AUA) symptom scores decreased regardless of the type of partial gland ablation performed, with subtotal ablation having the lowest score compared with hemiablation and focal cryoablation. No patient developed a fistula in the primary group, and 1 (9%) patient developed a fistula in the salvage group. Conclusion: Individualized partial gland cryoablation of the prostate is able to achieve excellent oncological and functional outcomes in select men with localized prostate cancer.

Tumour markers of prostate cancer: The post-PSA era

Although PSA-based prostate cancer (PCa) screening had a positive impact in reducing PCa mortality, it also led to overdiagnosis, overtreatment and to a significant number of unnecessary biopsies. In the post-PSA era, new biomarkers have emerged that can complement the information given by PSA, towards a better cancer diagnostic specificity, and also allow a better estimate of the aggressiveness of the disease and its clinical outcome. That means those markers have the potential to assist the clinician in the decision-making processes, such as whether or not to perform a biopsy, and to make the best treatment choice among the new therapeutic options available, including active surveillance (AS) in lower risk disease. In this article, we will review several of those more recent diagnostic markers (4Kscore®, [-2]proPSA and Prostate Health Index (PHI), SelectMDx®, ConfirmMDx®, Progensa® Prostate Cancer Antigen 3, Mi-Prostate Score, ExoDx™ Prostate Test, the Stockholm-3 test and ERSPC risk calculators) and prognostic markers (OncotypeDX® Genomic Prostate Score, Prolaris®, Decipher® and ProMark®). We will also address some new liquid biopsy approaches - circulating tumour cells and cell-free DNA (cfDNA) - with a potential role in metastatic castration-resistant PCa and will briefly give some future perspectives, mostly outlooking epigenetic markers.

The Impact of Body Mass Index on Freedom From Therapeutic Intervention and Quality of Life in Active Surveillance Prostate Cancer Patients

OBJECTIVE

The objective of this study was to evaluate the impact of body mass index (BMI) on overall survival, freedom from distant metastases, rates of therapeutic intervention (TI), and quality of life (QOL) in active surveillance (AS) prostate cancer patients.

MATERIALS AND METHODS

Three hundred forty consecutive, prospectively evaluated AS patients underwent a staging transperineal template-guided mapping biopsy before AS enrollment and were stratified by BMI (<25, 25 to 29.9, 30 to 34.9, and >35 kg/m2). Evaluated outcomes included overall survival, freedom from distant metastases, TI, QOL to include urinary, bowel, sexual function and depression and serial postvoid residual urine measurements. The relationship between BMI and anterior prostate cancer distribution was evaluated. Repeat biopsy was based on prostate specific antigen kinetics, abnormal digital rectal examination and patient preference.

RESULTS

Of the 340 patients, 323 (95%) were Gleason 3+3 and 17 patients (5.0%) were Gleason 3+4. The median follow-up was 5.2 years (range: 1 to 14 y). At 10 years, TI was instituted in 4.7%, 2.2%, 9.5%, and 25.0% of patients in BMI cohorts <25, 25 to 29.9, 30 to 34.9, and ≥35 (P=0.075). No patient has developed distant metastases. The median time to TI was 4.86 years. In multivariate analysis, TI was most closely predicted by prostate specific antigen density (P=0.071). At 8 years, no statistical differences in urinary function, bowel function, depression or postvoid residual were noted. However, a trend for erectile dysfunction was identified (P=0.106).

CONCLUSION

At 10 years, BMI did not statistically predict for TI, geographic distribution of prostate cancer or QOL parameters.

MRI and Targeted Biopsy Essential Tools for an Accurate Diagnosis and Treatment Decision Making in Prostate Cancer

Prostate cancer (PCa) is one of the most frequent causes of cancer death worldwide. Historically, diagnosis was based on physical examination, transrectal (TRUS) images, and TRUS biopsy resulting in overdiagnosis and overtreatment. Recently magnetic resonance imaging (MRI) has been identified as an evolving tool in terms of diagnosis, staging, treatment decision, and follow-up. In this review we provide the key studies and concepts of MRI as a promising tool in the diagnosis and management of prostate cancer in the general population and in challenging scenarios, such as anteriorly located lesions, enlarged prostates determining extracapsular extension and seminal vesicle invasion, and prior negative biopsy and the future role of MRI in association with artificial intelligence (AI).

Subtotal surgical therapy for localized prostate cancer: a single-center precision prostatectomy experience in 25 patients, and SEER-registry data analysis

Background

We recently described a novel form of focal therapy for prostate cancer (CaP)—the precision prostatectomy. Here we report on the first 25 consecutive patients. Further, utilizing Surveillance Epidemiology and End Results (SEER)-registry data, we assess long-term oncological efficacies of various focal therapy techniques.

Methods

Men who met the criteria: (I) PSA ≤15 ng/mL, (II) stage ≤cT2, (III) dominant unilateral lesion with Gleason ≤4+3 with any number or percentage (%) of cores involved ipsilaterally on biopsy, (IV) no primary Gleason ≥4 contralaterally, and (V) preoperative erectile function score (IIEF-5/SHIM) of ≥17 with/without PDE-5i were included in this prospective, single-arm, IDEAL stage 2b study (December 2016 to July 2017). Safety of the technique, and intermediate-term urinary, sexual and oncological outcomes were studied. Descriptive statistics and Kaplan-Meier (KM) analysis were used to assess 12-month urinary continence (0–1 pad), 12-month sexual potency (SHIM ≥17), and 36-month freedom from clinically-significant CaP (grade group ≥2), radical treatment, metastatic disease and mortality. SEER-registry was queried to evaluate CaP-specific survival in patients undergoing hyperthermia, cryotherapy, or segmental prostatectomy.

Results

At study entry, the median (IQR) age, PSA and SHIM score were 56.5 (53.1–62.3) years, 4.2 (3.8–5.9) ng/mL and 23 [20–25], respectively. Only 1 patient met the Epstein criteria for active surveillance. All patients were followed for a minimum of 2 years. At 12 months, from a functional standpoint, all patients were continent. Twenty-three (92%) patients were potent at 12 months. From an oncological standpoint, at 36 months, the KM analysis (95% CI) demonstrated a 96.2% (92.9–98.7) rate of freedom from clinically-significant CaP and a 92.7% (88.9–97.2) rate of freedom from radical treatment. All patients were alive and free of metastatic disease at the latest follow-up. Analysis of the SEER-registry data demonstrated 10-year CaP-specific survival rates of 91.6% to 97.7% among the 3 studied modalities, P=0.298.

Conclusions

Precision prostatectomy is feasible, technically safe, and offers excellent postoperative functional results. At 36 months of follow-up, the oncological outcomes and secondary procedure rates appear to be at-par with the ablative forms of focal therapy.

A new three-step method for using inverse propensity weighting with latent class analysis

Bias-adjusted three-step latent class analysis (LCA) is widely popular to relate covariates to class membership. However, if the causal effect of a treatment on class membership is of interest and only observational data is available, causal inference techniques such as inverse propensity weighting (IPW) need to be used. In this article, we extend the bias-adjusted three-step LCA to incorporate IPW. This approach separates the estimation of the measurement model from the estimation of the treatment effect using IPW only for the later step. Compared to previous methods, this solves several conceptual issues and more easily facilitates model selection and the use of multiple imputation. This new approach, implemented in the software Latent GOLD, is evaluated in a simulation study and its use is illustrated using data of prostate cancer patients.

25-year perspective on prostate cancer: Conquering frontiers and understanding tumor biology

Major changes in the field of prostate cancer over the last 25 years include the implementation of prostate specific antigen screening and the recognition that BRCA confers hereditary risk of prostate cancer. Quality of life and survivorship have driven risk stratification for localized prostate cancer, facilitated by molecular signatures and leading to increased acceptance of active surveillance as a mainstream treatment option. Advances in technology have improved efficacy and reduced toxicity in both radical prostatectomy and radiation therapy for localized prostate cancer. Improved understanding of the androgen receptor has yielded substantially more effective therapies. Future growth areas include personalized treatment based on genomic and genetic information, theranostics radiopharmaceuticals, and more aggressive treatment of metastatic disease to include focal therapy. Multidisciplinary management between specialized urologists, radiation oncologists, and medical oncologists remains central to maximizing patient outcomes.

New Molecular Mechanisms and Clinical Impact of circRNAs in Human Cancer

Simple Summary

Circular RNAs (circRNAs) belong to a new class of non-coding RNAs implicated in cellular physiological functions but also in the evolution of various human pathologies. Due to their circular shape, circRNAs are resistant to degradation by exonuclease activity, making them more stable than linear RNAs. Several findings reported that circRNAs are aberrantly modulated in human cancer tissues, thus affecting carcinogenesis and metastatization. We aim to report the most recent and relevant results about novel circRNA functions and molecular regulation, to dissert about their role as reliable cancer biomarkers, and to hypothesize their contribution to multiple hallmarks of cancer.

Abstract

Next generation RNA sequencing techniques, implemented in the recent years, have allowed us to identify circular RNAs (circRNAs), covalently closed loop structures resulting in RNA molecules that are more stable than linear RNAs. This class of non-coding RNA is emerging to be involved in a variety of cell functions during development, differentiation, and in many diseases, including cancer. Among the described biological activities, circRNAs have been implicated in microRNA (miRNA) sequestration, modulation of protein–protein interactions and regulation of mRNA transcription. In human cancer, circRNAs were implicated in the control of oncogenic activities such as tumor cell proliferation, epithelial-mesenchymal transition, invasion, metastasis and chemoresistance. The most widely described mechanism of action of circRNAs is their ability to act as competing endogenous RNAs (ceRNAs) for miRNAs, lncRNAs and mRNAs, thus impacting along their axis, despite the fact that a variety of additional mechanisms of action are emerging, representing an open and expanding field of study. Furthermore, research is currently focusing on understanding the possible implications of circRNAs in diagnostics, prognosis prediction, effectiveness of therapies and, eventually, therapeutic intervention in human cancer. The purpose of this review is to discuss new knowledge on the mechanisms of circRNA action, beyond ceRNA, their impact on human cancer and to dissect their potential value as biomarkers and therapeutic targets.

How are emotional distress and reassurance expressed in medical consultations for people with long-term conditions who were unable to receive curative treatment? A pilot observational study with huntington's disease and prostate cancer

Objective

It is unclear whether how people with long-term conditions express distress, and how clinicians respond, influences perceptions of consultation outcomes. The pilot study examined emotional distress and reassurance in consultations with people whose long-term conditions (at the time of consultations) were treated using active surveillance or symptom management (as no curative treatment was suitable).

Methods

An observational pilot study was conducted involving consultations between people with long-term conditions and their respective clinician. Consultations between three clinicians (two Huntington’s Disease; one Prostate Cancer) and 22 people with long-term conditions (11 Huntington’s Disease; 11 Prostate Cancer) were audio-recorded. Participants also completed an expanded Consultation and Relational Empathy (CARE) Measure. Two researchers coded sessions using Verona Coding Definitions of Emotional Sequences (VR-CoDES/VR-CoDES-P). Code frequencies were calculated, t tests performed between conditions, and Pearson’s correlations performed for associations between CARE responses and clinician utterances.

Results

People with long-term conditions expressed emotional distress on average 4.45 times per session, averaging 1.09 Concern and 3.36 Cue utterances. Clinicians responded with more explicit (2.59) and space-providing (3.36), than non-explicit (1.86) and space-reducing (1.09), responses per session. Clinicians expressed spontaneous reassurance on average 5.18 times per session, averaging 3.77 Cognitive and 1.5 Affective reassurance utterances. Huntington’s Disease consultations featured significantly more 'Cues', 'Concerns' and 'Overall' 'Emotional Distress', and 'Cognitive' and 'Overall' ‘Reassurance'.

Conclusion

Emotional distress was expressed more using hints than explicit concern utterances. Clinicians predominantly explicitly explored distress rather than providing information/advice and provided advice using spontaneous cognitive reassurance. People with Huntington’s Disease expressed more concerns and received more reassurance, indicating different needs between conditions. Future research is required to explore emotional distress and reassurance in a larger sample of participants and long-term condition types, and how the practical implications of these findings may be used to enhance outcomes of consultations.

Trial registration

N/A.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-021-00833-z.

Target-Specific Magnetic Resonance Imaging of Human Prostate Adenocarcinoma Using NaDyF4-NaGdF4 Core-Shell Nanoparticles

We illustrate the development of NaDyF₄-NaGdF₄ core-shell nanoparticles (NPs) for targeting prostate cancer cells using a preclinical 9.4 T magnetic resonance imaging (MRI) of live animals. The NPs composed of paramagnetic Dy³⁺ and Gd³⁺ (T₂- and T₁-contrast agents, respectively) demonstrate proton relaxivities of r₁ = 20.2 mM^-1 s^-1 and r₂ = 32.3 mM^-1 s^-1 at clinical 3 T and r₁ = 9.4 mM^-1 s^-1 and r₂ = 144.7 mM^-1 s^-1 at preclinical 9.4 T. The corresponding relaxivity values per NP are r₁ = 19.4 × 10⁵ mM_NP^-1 s^-1 and r₂ = 33.0 × 10⁵ mM_NP^-1 s^-1 at 3 T and r₁ = 9.0 × 10⁵ mM_NP^-1 s^-1 and r₂ = 147.0 × 10⁵ mM_NP^-1 s^-1 at 9.4 T. In vivo active targeting of human prostate tumors grown in nude mice revealed docking of anti-prostate-specific membrane antigen (PSMA) antibody-tagged NPs at tumor sites post-24 h of their intravenous injection. On the other hand, in vivo passive targeting showed preferential accumulation of NPs at tumor sites only within 2 h of their injection, ascribed to the enhanced permeation and retention effect of the tumor. A biodistribution study employing the harvested organs of mice, post-24 h injection of NPs, quantified active targeting as nearly twice as efficient as passive targeting. These outcomes provide potential opportunities for noninvasive diagnosis using NaDyF₄-NaGdF₄ core-shell NPs for target-specific MRI.

A Novel Set of Immune-associated Gene Signature predicts Biochemical Recurrence in Localized Prostate Cancer Patients after Radical Prostatectomy

Background: Decision-making regarding biochemical recurrence (BCR) in localized prostate cancer (PCa) patients after radical prostatectomy (RP) mainly relies on clinicopathological parameters with a low predictive accuracy. Currently, accumulating evidence suggests that immune-associated genes (IAGs) play irreplaceable roles in tumorigenesis, progression and metastasis. Considering the critical role of immune in PCa, we therefore attempted to identify the novel IAGs signature and validate its prognostic value that can better forecast the risk for BCR and guide clinical treatment. Methods: RNA-sequencing and corresponding clinicopathological data were downloaded from the Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database. Weighted gene co-expression network analysis (WGCNA) was utilized to screen out the candidate module closely related to BCR, and univariate and LASSO Cox regression analyses were performed to build the gene signature. Kaplan-Meier (KM) survival analysis, time-dependent receiver operating curve (ROC), independent prognostic analysis and nomogram were also applied to evaluate the prognostic value of the signature. Besides, Gene ontology analysis (GO), Kyoto encyclopedia of genes and genomes (KEGG) and gene set enrichment analysis (GSEA) were used to explore potential biological pathways. Results: A total of six IAGs (SSTR1, NFATC3, NRP1, TUBB3, IL1R1, GDF15) were eventually identified and used to establish a novel IAGs signature. The Kaplan-Meier analysis revealed that patients with low-risk scores had longer recurrence-free survival (RFS) than those with high-risk scores in both GSE70769 and TCGA cohorts. Further, our signature was also proven to be a valuable independent prognostic factor for BCR. We also constructed a nomogram based on the gene signature and related clinicopathologic features, which excellently predict 1-year, 3-year and 5-year prognosis of localized PCa patients after RP. Moreover, functional enrichment analysis demonstrated the vital biological processes, and stratified GSEA revealed that a crucial immune-related pathway (T cell receptor signaling pathway) was notably enriched in the high-risk group. Conclusions: We successfully developed a novel robust IAGs signature that is powerful in BCR prediction in localized PCa patients after RP, and created a prognostic nomogram. In addition, the signature might help clinicians in selecting high-risk subpopulation, predicting survival status of patients and promoting more individualized therapies than traditional clinical factors.

[Active surveillance-much safety, little recruitment : Is it possible to extend the indication for "intermediate-risk" prostate cancer?]

BACKGROUND

In contrast to North America or Sweden, active surveillance (AS) has not yet become established in our country for suitable prostate carcinomas (PCa). The strict entry criteria specified by the guideline are not likely to improve the acceptance in the near future. In early detection, prostate-specific antigen (PSA) testing leads to high numbers of overtreatment. There are various reasons for the continued preference for radical surgery.

OBJECTIVES

The goal is to examine whether the heterogeneous group with intermediate-risk PCa contains tumors that may be eligible for AS.

MATERIALS AND METHODS

In the HAROW trial, 52 AS patients with differently defined intermediate-risk PCa were followed for a median of 85.6 months. Oncologic outcomes are reported.

RESULTS

Sixteen (30%) patients had a tumor of cT2b category, 21 (40%) had a Gleason score 3 + 4, 7 (14%) had ≥3 positive biopsy cores, 21 (40%) had a PSA >10 ng/ml, and 22 (42%) had a PSA density >0.2 ng/ml². Carcinoma-specific and metastasis-free survival were 100% and 96%, respectively. Thirty four patients discontinued AS in favor of invasive treatment, and an additional eight men maintained a noninvasive approach by switching to watchful waiting.

CONCLUSIONS

Efforts are under way to specify the criteria for patients with intermediate-risk PCa who may be eligible for AS. Tumors of cT2 category could be grouped together. The Gleason 4 fraction needs to be quantified because it determines the prognosis.

Malignant Evaluation and Clinical Prognostic Values of M6A RNA Methylation Regulators in Prostate Cancer

Objective: M6A RNA modification is closely associated with tumor genesis and progression of several malignancies; however, its role in prostate cancer (PCa) remains poorly understood.

Materials and methods: Expression data and corresponding clinicopathologic information were available freely from the Cancer Genome Atlas (TCGA) dataset. We compared the expression level of m6A RNA methylation regulators in PCa with different clinicopathologic characteristics and identified subgroups based on their expressions with consensus clustering. To build the signature and assess its prognostic value, several methods were used for the analysis, including univariate Cox regression analysis, Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis, time-dependent receiver operating curve (ROC), and Kaplan-Meier (KM) survival analysis.

Results: Most of the m6A RNA methylation regulators were differentially expressed not only between normal and tumor tissue but also among PCa stratified by different clinicopathologic characteristics. There were obvious differences between two clusters, cluster 1 and 2, regarding clinicopathologic features, and the recurrence-free survival (RFS) in cluster 2 was significantly worse than cluster 1. We developed an eleven-gene signature which exhibited a high prognostic value and was able to independently predict RFS. Moreover, a nomogram which integrated clinical information and the gene signature was capable of distinguishing high-risk recurrent patients.

Conclusion: These methylation regulators are correlated to clinicopathologic characteristics in PCa and a prognostic model using m6A methylation-related genes is constructed and of high predictive value for recurrence after RP.

Utilization of focal therapy for patients discontinuing active surveillance of prostate cancer: Recommendations of an international Delphi consensus

BACKGROUND

With the advancement of imaging technology, focal therapy (FT) has been gaining acceptance for the treatment of select patients with localized prostate cancer (CaP). We aim to provide details of a formal physician consensus on the utilization of FT for patients with CaP who are discontinuing active surveillance (AS).

METHODS

A 3-stage Delphi consensus on CaP and FT was conducted. Consensus was defined as agreement by ≥80% of physicians. An in-person meeting was attended by 17 panelists to formulate the consensus statement.

RESULTS

Fifty-six respondents participated in this interdisciplinary consensus study (82% urologist, 16% radiologist, 2% radiation oncology). The participants confirmed that there is a role for FT in men discontinuing AS (48% strongly agree, 39% agree). The benefit of FT over radical therapy for men coming off AS is: less invasive (91%), has a greater likelihood to preserve erectile function (91%), has a greater likelihood to preserve urinary continence (91%), has fewer side effects (86%), and has early recovery post-treatment (80%). Patients will need to undergo mpMRI of the prostate and/or a saturation biopsy to determine if they are potential candidates for FT. Our limitations include respondent's biases and that the participants of this consensus may not represent the larger medical community.

CONCLUSIONS

FT can be offered to men coming off AS between the age of 60 to 80 with grade group 2 localized cancer. This consensus from a multidisciplinary, multi-institutional, international expert panel provides a contemporary insight utilizing FT for CaP in select patients who are discontinuing AS.

Active surveillance for prostate cancer: selection criteria, guidelines, and outcomes

INTRODUCTION

Active surveillance (AS) has been widely adopted for the management of men with low-risk prostate cancer. However, there is still a lack of consensus surrounding the optimal approach for monitoring men in AS protocols. While conservative management aims to reduce the burden of invasive testing without compromising oncological safety, inadequate assessment can result in misclassification and unintended over- or undertreatment, leading to increased patient morbidity, cost, and undue risk. No universally accepted AS protocol exists, although numerous strategies have been developed in an attempt to optimize the management of clinically localized disease. Variability in selection criteria, reclassification, triggers for definitive treatment, and follow-up exists between guidelines and institutions for AS. In this review, we summarize the landscape of AS by providing an overview of the existing AS protocols, guidelines, and their published outcomes.

METHODS

A comprehensive electronic search was performed to identify representative studies and guidelines pertaining to AS selection criteria and outcomes.

CONCLUSION

While AS is a safe and increasingly utilized treatment modality for lower-risk forms of PCa, ongoing research is needed to optimize patient selection as well as surveillance protocols along with improved implementation across practices. Further, assessment of companion risk assessment tools, such as mpMRI and tissue-based biomarkers, is also needed and will require rigorous prospective study.

Comparing confirmatory biopsy outcomes between MRI-targeted biopsy and standard systematic biopsy among men being enrolled in prostate cancer active surveillance

OBJECTIVES

To evaluate the ability of magnetic resonance imaging (MRI)-targeted biopsy combined with systematic biopsy (MRI-biopsy) to reduce negative biopsies and detect clinically significant prostate cancer compared to systematic biopsy (SB) alone in the confirmatory biopsy setting using matched cohorts.

PATIENTS AND METHODS

Patients were identified from an active surveillance database who had a previously positive transrectal ultrasonography-guided SB followed by a confirmatory biopsy at a single institution between 2006 and 2019. Patients were divided into two cohorts based on confirmatory biopsy technique: SB alone or MRI-biopsy (which included MRI-targeted and systematic biopsies). Cohorts were then matched on age, prostate-specific antigen (PSA) level, number of positive cores on initial biopsy and initial biopsy Gleason grade group (GG). Logistic regression was performed to identify associations with confirmatory biopsy upgrading.

RESULTS

After matching, 514 patients were identified (257 per cohort). PSA, prostate volume and PSA density prior to initial biopsy, in addition to total number of initial biopsy positive cores and GG, were similar between the matched cohorts. After confirmatory biopsy, 118/257 patients (45.9%) in the MRI-biopsy cohort were upgraded compared to 46/257 patients (17.9%) in the SB cohort (P < 0.001). The rate of negative confirmatory biopsy was 32/257 (12.5%) compared to 97/257 (37.7%) in the MRI-biopsy and SB cohorts, respectively (P < 0.001). Confirmatory MRI-biopsy was associated with greater odds of confirmatory biopsy upgrade from GG 1 to ≥GG 2 compared to SB alone (odds ratio 3.62, 95% confidence interval 1.97-6.63; P < 0.001).

CONCLUSION

The addition of MRI-targeted biopsies to SB in the confirmatory biopsy setting among men with previously detected prostate cancer resulted in fewer negative confirmatory biopsies and detection of more clinically significant prostate cancer compared to SB alone.