Intermediate-risk Prostate Cancer: Stratification and Management

Organ-confined pT2 ISUP4/5 vs. nonorgan confined pT3/4 ISUP2 vs. ISUP3 prostate cancer: Differences in biochemical recurrence-free survival after radical prostatectomy

BACKGROUND

To test for differences in organ-confined pathological tumor stage (pT) and intermediate International Society of Urological Pathologists (ISUP) grade vs. nonorgan confined pT stage and high ISUP grade and biochemical recurrence (BCR) after radical prostatectomy (RP).

METHODS

Relying on a tertiary-care database, prostate cancer patients undergoing RP between January 2014 and December 2021 were stratified according to their combination of pT stage and ISUP grade in RP specimens (pT2 ISUP4/5 vs. pT3/4 ISUP2 vs. pT3/4 ISUP3). As Active Surveillance is recommended in ISUP1, these patients were excluded. Moreover, patients with pT2 ISUP2/3 are known for their good prognosis and pT3/4 ISUP4/5 patients for their poor prognosis. Therefore, these patients were also excluded from analyses. Kaplan-Meier survival analyses and multivariable Cox regression models addressed BCR after RP.

RESULTS

Of 215 RP patients, 29 (13%) exhibited pT2 ISUP4/5 vs. 122 (57%) pT3/4 ISUP2 vs. 64 (30%) pT3/4 ISUP3 pathology. In survival analyses, 3-year BCR-free survival rates were 95% in pT2 ISUP4/5 vs. 88% in pT3/4 ISUP2 vs. 65% in pT3/4 ISUP3 patients (P < 0.001). In multivariable Cox regression models addressing BCR, pT3/4 ISUP3 pathology was associated with higher BCR rate relative to pT2 ISUP4/5 pathology (hazard ratio 3.42, 95% confidence interval 1.07-10.94; P = 0.039), but not pT3/4 ISUP2 pathology (P = 0.6).

CONCLUSION

Compared to prostate cancer patients with pT2 ISUP4/5 pathology, the combination of pT3/4 ISUP3 pathology is associated with higher risk of BCR after RP. In consequence, patients with pT3/4 ISUP3 pathology should be considered for a closer postoperative follow-up.

Metabolic imaging across scales reveals distinct prostate cancer phenotypes

Hyperpolarised magnetic resonance imaging (HP-13C-MRI) has shown promise as a clinical tool for detecting and characterising prostate cancer. Here we use a range of spatially resolved histological techniques to identify the biological mechanisms underpinning differential [1-13C]lactate labelling between benign and malignant prostate, as well as in tumours containing cribriform and non-cribriform Gleason pattern 4 disease. Here we show that elevated hyperpolarised [1-13C]lactate signal in prostate cancer compared to the benign prostate is primarily driven by increased tumour epithelial cell density and vascularity, rather than differences in epithelial lactate concentration between tumour and normal. We also demonstrate that some tumours of the cribriform subtype may lack [1-13C]lactate labelling, which is explained by lower epithelial lactate dehydrogenase expression, higher mitochondrial pyruvate carrier density, and increased lipid abundance compared to lactate-rich non-cribriform lesions. These findings highlight the potential of combining spatial metabolic imaging tools across scales to identify clinically significant metabolic phenotypes in prostate cancer.

Diffuse Maculopapular Dermatitis Associated With Leuprorelin Acetate Androgen Deprivation Therapy

Androgen deprivation therapy (ADT) is one of the effective treatment methods for prostate cancer, often used with radiation therapy. Among the key ADT agents is leuprolide, a synthetic gonadotropin-releasing hormone agonist, which effectively suppresses testosterone production which is a requisite for the growth and division of prostate cancer cells. However, leuprolide is associated with several well-known side effects and less common dermatological reactions. In this case, we present an 80-year-old male patient with stage IIB prostate cancer who developed diffuse maculopapular dermatitis following leuprolide acetate ADT. The patient first experienced mild dermatitis following the fifth monthly 7.5 mg leuprolide injection before it developed into a general body rash after six injections. The dermatitis manifested on the patient's arms, thighs, calves, dorsum, and back of hands but sparing the abdomen, face, and neck. The pruritic dermatitis was managed successfully with a three-week course of prednisone which led to complete resolution without long-term sequelae. This case highlights the importance of recognizing and managing dermatological side effects associated with ADT. Clinicians should maintain an index of suspicion and act promptly when these side effects manifest. Systematic reporting and further research are essential to enhance patient safety and understanding of drug-related dermatological manifestations.

Risk-Adapted Strategy Combining Magnetic Resonance Imaging and Prostate-Specific Antigen Density to Individualize Biopsy Decision in Patients With PI-RADS 3 ``Gray Zone'' Lesions

INTRODUCTION

Recent guidelines suggest that biopsy may be omitted in some groups of patients with PI-RADS 3 lesions on mpMRI. In this study, we aimed to evaluate biopsy strategies involving prostate-specific antigen density (PSAd) to avoid unnecessary biopsy versus the risk of missing clinically significant prostate cancer (csPCa) in patients with PI-RADS 3 lesions.

MATERIAL AND METHODS

Data of 616 consecutive patients who underwent PSAd and mpMRI before prostate biopsy between January 2017 and January 2022 at a single center were retrospectively assessed. All of these patients underwent combined cognitive or fusion targeted biopsy of suspicious lesions and transrectal ultrasonography guided systematic biopsy. PI-RADS 3 based strategies with PSAd and mpMRI combination were created. For each strategy, avoided unnecessary biopsy, reduced ISUP Grade 1, and missed ISUP Grade ≥ 2 ratios were determined. Decision curve analysis (DCA) was used to statistically compare the net benefit of each strategy.

RESULTS

DCA revealed that patients who had PI-RADS 3 lesions with PSAd ≥ 0.2, and/or patients who had PI-RADS 4 and 5 lesions had the most benefit, under the threshold probability level between 10% and 50%, which avoided 48.2% unnecessary prostate biopsies and reduced 51% of ISUP grade 1 cases, while missed 17.5% of ISUP grade ≥ 2 cases. (22.1% for ISUP grade 2 and 8.8% for ISUP grade ≥ 3). Strategy 1 (PI-RADS 4-5 and/or PSAd ≥ 0.2), 3 (PI-RADS 4-5 and/or PI-RADS 3 if PSAd ≥ 0.15), and 7 (PI-RADS 4-5 and/or PI-RADS 3 if PSAd ≥ 0.15 and/or PI-RADS 2 if PSAd ≥ 0.2) were the next three best strategies.

CONCLUSION

mpMRI combined with PSAd strategies reduced biopsy attempts in PI-RADS 3 lesions. Using these strategies, the advantage of avoiding biopsy and the risk of missing the diagnosis of csPCa can be discussed with the patient, and the biopsy decision can be made afterwards.

Which Patients with Prostate Cancer and Lymph Node Uptake at Preoperative Prostate-specific Membrane Antigen Positron Emission Tomography/Computerized Tomography Scan Are at a Higher Risk of Prostate-specific Antigen Persistence After Radical Prostatectomy? Identifying Indicators of Systemic Disease by Integrating Clinical, Magnetic Resonance Imaging, and Functional Imaging Parameters

BACKGROUND

The role of local therapies including radical prostatectomy (RP) in prostate cancer (PCa) patients with clinical lymphadenopathies on prostate-specific membrane antigen (PSMA) positron emission tomography/computerized tomography (PET/CT) has scarcely been explored. Limited data are available to identify men who would benefit from RP; on the contrary, those more likely to benefit already have systemic disease.

OBJECTIVE

We aimed to assess the predictors of prostate-specific antigen (PSA) persistence in surgically managed PCa patients with lymphadenopathies on a PSMA PET/CT scan by integrating clinical, magnetic resonance imaging (MRI), and PSMA PET/CT parameters.

DESIGN, SETTING, AND PARTICIPANTS

We identified 519 patients treated with RP and extended lymph node dissection, and who received preoperative PSMA PET between 2017 and 2022 in nine referral centers. Among them, we selected 88 patients with nodal uptake at preoperative PSMA PET (miTxN1M0).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The outcome was PSA persistence, defined as a PSA value of ≥0.1 ng/ml at the first measurement after surgery. Multivariable logistic regression models tested the predictors of PSA persistence. Covariates consisted of biopsy International Society of Urological Pathology (ISUP) grade group, clinical stage at MRI, and number of positive spots at a PET/CT scan. A regression tree analysis stratified patients into risk groups based on preoperative characteristics.

RESULTS AND LIMITATIONS

Overall, lymph node invasion (LNI) was detected in 63 patients (72%) and 32 (36%) experienced PSA persistence after RP. At multivariable analyses, having more than two lymph nodal positive findings at PSMA PET, seminal vesicle invasion (SVI) at MRI, and ISUP grade group >3 at biopsy were independent predictors of PSA persistence (all p < 0.05). At the regression tree analysis, patients were stratified in four risk groups according to biopsy ISUP grade, number of positive findings at PET/CT, and clinical stage at MRI. The model depicted good discrimination at internal validation (area under the curve 78%).

CONCLUSIONS

One out of three miN1M0 patients showed PSA persistence after surgery. Patients with ISUP grade 2-3, as well as patients with organ-confined disease at MRI and a single or two positive nodal findings at PET are those in whom RP may achieve the best oncological outcomes in the context of a multimodal approach. Conversely, patients with a high ISUP grade and extracapsular extension or SVI or more than two spots at PSMA PET should be considered as potentially affected by systemic disease upfront.

PATIENT SUMMARY

Our novel and straightforward risk classification integrates currently available preoperative risk tools and should, therefore, assist physician in preoperative counseling of men candidates for radical treatment for prostate cancer with positive lymph node uptake at prostate-specific membrane antigen positron emission tomography.

Effects of Androgen Deprivation Therapy on Prostate Cancer Outcomes According to Competing Event Risk: Secondary Analysis of a Phase 3 Randomised Trial

BACKGROUND

Previous studies indicate that the benefit of short-term androgen deprivation therapy (ADT) with radiotherapy (RT) for prostate cancer depends on competing risks.

OBJECTIVE

To determine whether a quantitative method to stratify patients by risk for competing events (omega score) could identify subgroups that selectively benefit from ADT.

DESIGN, SETTING, AND PARTICIPANTS

An ancillary analysis of NRG/RTOG 9408 phase 3 trial (NCT00002597) involving 1945 prostate cancer patients was conducted.

INTERVENTION

Short-term ADT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We applied generalised competing event regression models incorporating age, performance status, comorbidity, T category, Gleason score (GS), and prostate-specific antigen (PSA), to stratify patients according to relative hazards for primary cancer-related events (distant metastasis or prostate cancer death) versus competing noncancer mortality. We tested interactions between ADT and subgroups defined by standard risk criteria versus relative risk (RR) using the omega score.

RESULTS AND LIMITATIONS

T2b, higher GS, and higher PSA were associated with an increased RR for cancer-related versus competing mortality events (a higher omega score); increased age and comorbidity were associated with a decreased omega score. Of 996 patients with low-risk/favourable intermediate-risk (FIR) disease, 286 (28.7%) had a high omega score (≥0.314). Of 768 patients with unfavourable intermediate-risk disease, 175 (22.8%) had a low omega score. The overall discordance in risk classification was 26.1%. Both standard criteria and omega score identified significant interactions for the effect of ADT on cancer-related events and late mortality in low- versus high-risk subgroups. Within the low-risk/FIR subgroup, a higher omega score identified patients in whom ADT significantly reduced cancer events and improved event-free survival. Limitations are the need for external/prospective validation and lower RT doses than contemporary standards.

CONCLUSIONS

Stratification based on competing event risk is useful for identifying prostate cancer patients who selectively benefit from ADT.

PATIENT SUMMARY

We analysed the effectiveness of androgen deprivation therapy (ADT) for localised prostate cancer among patients, defined by the relative risk (RR) for cancer versus noncancer events. Among patients with traditional low-risk/favourable intermediate-risk disease, those with a higher RR benefitted from short-term ADT.

Ex Vivo Fluorescence Confocal Microscopy of MRI-Guided Targeted Prostate Biopsies for Rapid Detection of Clinically Significant Carcinomas-A Feasibility Study

BACKGROUND

MRI-guided prostate biopsies from visible tumor-specific lesions (TBx) can be used to diagnose clinically significant carcinomas (csPCa) requiring treatment more selectively than conventional systematic biopsies (SBx). Ex vivo fluorescence confocal microscopy (FCM) is a novel technique that can be used to examine TBx prior to conventional histologic workup.

METHODS

TBx from 150 patients were examined with FCM on the day of collection. Preliminary findings were reported within 2 h of collection. The results were statistically compared with the final histology.

RESULTS

27/40 (68%) of the csPCa were already recognized in the intraday FCM in accordance with the results of conventional histology. Even non-significant carcinomas (cisPCa) of the intermediate and high-risk groups (serum prostate-specific antigen (PSA) > 10 or 20 ng/mL) according to conventional risk stratifications were reliably detectable. In contrast, small foci of cisPCa were often not detected or were difficult to distinguish from reactive changes.

CONCLUSION

The rapid reporting of preliminary FCM findings helps to reduce the psychological stress on patients, and can improve the clinical management of csPCa. Additional SBx can be avoided in individual cases, leading to lower rates of complications and scarring in the future surgical area. Additional staging examinations can be arranged without losing time. FCM represents a promising basis for future AI-based diagnostic algorithms.

High expression of Trop2 is associated with aggressive localized prostate cancer and is a candidate urinary biomarker

Distinguishing indolent from clinically significant localized prostate cancer is a major clinical challenge and influences clinical decision-making between treatment and active surveillance. The development of novel predictive biomarkers will help with risk stratification, and clinical decision-making, leading to a decrease in over or under-treatment of patients with prostate cancer. Here, we report that Trop2 is a prognostic tissue biomarker for clinically significant prostate cancer by utilizing the Canary Prostate Cancer Tissue Microarray (CPCTA) cohort composed of over 1100 patients from a multi-institutional study. We demonstrate that elevated Trop2 expression is correlated with worse clinical features including Gleason score, age, and pre-operative PSA levels. More importantly, we demonstrate that elevated Trop2 expression at radical prostatectomy predicts worse overall survival in men undergoing radical prostatectomy. Additionally, we detect shed Trop2 in urine from men with clinically significant prostate cancer. Our study identifies Trop2 as a novel tissue prognostic biomarker and a candidate non-invasive marker for prostate cancer.

Image-Based Subtype Classification for Glioblastoma Using Deep Learning: Prognostic Significance and Biologic Relevance

PURPOSE

To apply deep learning algorithms to histopathology images, construct image-based subtypes independent of known clinical and molecular classifications for glioblastoma, and produce novel insights into molecular and immune characteristics of the glioblastoma tumor microenvironment.

MATERIALS AND METHODS

Using whole-slide hematoxylin and eosin images from 214 patients with glioblastoma in The Cancer Genome Atlas (TCGA), a fine-tuned convolutional neural network model extracted deep learning features. Biclustering was used to identify subtypes and image feature modules. Prognostic value of image subtypes was assessed via Cox regression on survival outcomes and validated with 189 samples from the Clinical Proteomic Tumor Analysis Consortium (CPTAC) data set. Morphological, molecular, and immune characteristics of glioblastoma image subtypes were analyzed.

RESULTS

Four distinct subtypes and modules (imClust1-4) were identified for the TCGA patients with glioblastoma on the basis of the image feature data. The glioblastoma image subtypes were significantly associated with overall survival (OS; P = .028) and progression-free survival (P = .003). Apparent association was also observed for disease-specific survival (P = .096). imClust2 had the best prognosis for all three survival end points (eg, after 25 months, imClust2 had >7% surviving patients than the other subtypes). Examination of OS in the external validation using the unseen CPTAC data set showed consistent patterns. Multivariable Cox analyses confirmed that the image subtypes carry unique prognostic information independent of known clinical and molecular predictors. Molecular and immune profiling revealed distinct immune compositions of the tumor microenvironment in different image subtypes and may provide biologic explanations for the patterns in patients' outcomes.

CONCLUSION

Our image-based subtype classification on the basis of deep learning models is a novel tool to refine risk stratification in cancers. The image subtypes detected for glioblastoma represent a promising prognostic biomarker with distinct molecular and immune characteristics and may facilitate developing novel, individualized immunotherapies for glioblastoma.

Oncological outcomes in robot-assisted radical prostatectomy: the value of PSA density as a preoperative predictive factor

Background

Pretreatment assessment of patients diagnosed with localized prostate cancer (PCa) is essential for therapeutic decision-making. Currently available staging systems based on prostate-specific antigen (PSA), Gleason score, and clinical stage allow for determining the prognostic characteristics of these patients. Several studies have evaluated the preoperative use of prostate-specific antigen density (PSAD) as a prognostic factor for further risk stratification. To date, the role of PSAD in this setting is still an object of debate.

Objectives

The present analysis aimed to assess the predictive potential of PSAD for adverse oncological outcomes after robot-assisted radical prostatectomy (RARP) and to compare its accuracy to preoperative PSA (pPSA).

Design and methods

We retrospectively reviewed 427 patients diagnosed with localized PCa who underwent RARP at a single institution between January 2015 and January 2020. Generating receiver operator characteristic (ROC) curves, calculating areas under the curves (AUCs), and using a linear regression model, we analyzed the association of PSAD and pPSA with postoperative positive surgical margins (PSM), Gleason score ⩾ 7, persistent PSA, and biochemical recurrence (BCR), with a median follow-up of 47 months.

Results

PSAD showed a significant association with PSM (p < 0.0001), PSA persistence (p < 0.0001), and Gleason ⩾ 7 (p < 0.0001), without being statistically significant in predicting BCR (p = 0.098). The predictive value of PSAD was comparable to pPSA for outcomes of PSA persistence (AUC 0.727 versus 0.771) and Gleason ⩾ 7 (AUC 0.683 versus 0.649).

Conclusion

PSAD is a predictive factor for postoperative oncological outcomes of PSM, Gleason score ⩾ 7, and persistence of PSA. Despite the need for further studies, PSAD could be useful as a prognostic parameter in conjunction with established staging systems.

Imaging tumor lactate is feasible for identifying intermediate-risk prostate cancer patients with postsurgical biochemical recurrence

While radical prostatectomy remains the mainstay of prostate cancer (PCa) treatment, 20 to 40% of patients develop postsurgical biochemical recurrence (BCR). A particularly challenging clinical cohort includes patients with intermediate-risk disease whose risk stratification would benefit from advanced approaches that complement standard-of-care diagnostic tools. Here, we show that imaging tumor lactate using hyperpolarized 13C MRI and spatial metabolomics identifies BCR-positive patients in two prospective intermediate-risk surgical cohorts. Supported by spatially resolved tissue analysis of established glycolytic biomarkers, this study provides the rationale for multicenter trials of tumor metabolic imaging as an auxiliary tool to support PCa treatment decision-making.

Performance of 18F-DCFPyL PET/CT in Primary Prostate Cancer Diagnosis, Gleason Grading and D'Amico Classification: A Radiomics-Based Study

This study aimed to investigate the performance of 18F-DCFPyL positron emission tomography/computerized tomography (PET/CT) models for predicting benign-vs-malignancy, high pathological grade (Gleason score > 7), and clinical D'Amico classification with machine learning. The study included 138 patients with treatment-naïve prostate cancer presenting positive 18F-DCFPyL scans. The primary lesions were delineated on PET images, followed by the extraction of tumor-to-background-based general and higher-order textural features by applying five different binning approaches. Three layer-machine learning approaches were used to identify relevant in vivo features and patient characteristics and their relative weights for predicting high-risk malignant disease. The weighted features were integrated and implemented to establish individual predictive models for malignancy (Mm), high path-risk lesions (by Gleason score) (Mgs), and high clinical risk disease (by amico) (Mamico). The established models were validated in a Monte Carlo cross-validation scheme. In patients with all primary prostate cancer, the highest areas under the curve for our models were calculated. The performance of established models as revealed by the Monte Carlo cross-validation presenting as the area under the receiver operator characteristic curve (AUC): 0.97 for Mm, AUC: 0.73 for Mgs, AUC: 0.82 for Mamico. Our study demonstrated the clinical potential of 18F-DCFPyL PET/CT radiomics in distinguishing malignant from benign prostate tumors, and high-risk tumors, without biopsy sampling. And in vivo 18F-DCFPyL PET/CT can be considered a noninvasive tool for virtual biopsy for personalized treatment management.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43657-023-00108-y.

Clinical efficacy of prostate PI-RADS V2.1 score combined with serum PSA-related indicators in the detection of gray zone prostate cancer

PURPOSE

The purpose of this study is to improve the diagnostic accuracy of gray zone prostate cancer evaluation by combining the prostate imaging report and data system version 2.1 (PI-RADS V2.1) score with serum prostate-specific antigen (PSA).

METHODS

We analyzed data from 212 men suspected of having prostate cancer and compared PSA-related indicators and PI-RADS V2.1 scores between 96 patients with prostate cancer and 116 without prostate cancer. By contrasting PI-RADS V2.1 scores with serum PSA-related markers, the diagnostic precision in the detection of grey zone prostate cancer was assessed.

RESULTS

The median PI-RADS V2.1 scores and serum tPSA levels of patients with prostate cancer were significantly higher (P < 0.05). The PI-RADS V2.1 score correlated positively with serum tPSA, PSA density (PSAD), and prostate health index (PHI) levels (P < 0.05) and negatively correlated with fPSA/tPSA concentrations (P < 0.05). Logistic regression identified risk factors including family history, PI-RADS V2.1 score, tPSA, PSAD, and PHI, with prostate volume and fPSA/tPSA as protective factors (P < 0.05). Combining serum PSA-related indicators with the PI-RADS V2.1 score improved diagnostic accuracy for gray zone prostate cancer (AUC 0.986, specificity 99.14%, sensitivity 92.71%).

CONCLUSION

The presence of a family history, a high PI-RADS V2.1 score, and elevated serum PSA-related markers contribute to high prostate cancer risk and development. The combined use of these indicators offers superior predictive value in detecting prostate cancer compared to a single indicator.

Active surveillance should not be routinely considered in ISUP grade group 2 prostate cancer

Active surveillance has been proposed as a therapeutic option in selected intermediate risk patients with biopsy grade group 2 prostate cancer. However, its oncologic safety in this setting is debated. Therefore, we conducted a non-systematic literature research of contemporary surveillance protocols including patients with grade group 2 disease to collect the most recent evidence in this setting. Although no randomized controlled trial compared curative-intent treatments, namely radical prostatectomy and radiotherapy vs. active surveillance in patients with grade group 2 disease, surgery is associated with a benefit in terms of disease control and survival when compared to expectant management in the intermediate risk setting. Patients with grade group 2 on active surveillance were at higher risk of disease progression and treatment compared to their grade group 1 counterparts. Up to 50% of those patients were eventually treated at 5 years, and the metastases-free survival rate was as low as 85% at 15-years. When considering low- and intermediate risk patients treated with radical prostatectomy, grade group 2 was one of the strongest predictors of grade upgrading and adverse features. Available data is insufficient to support the oncologic safety of active surveillance in all men with grade group 2 prostate cancer. Therefore, those patients should be counselled regarding the oncologic efficacy of upfront active treatment modalities and the lack of robust long-term data supporting the safety of active surveillance in this setting.

MRI-Guided Targeted and Systematic Prostate Biopsies as Prognostic Indicators for Prostate Cancer Treatment Decisions

The standard procedure for the diagnosis of prostate carcinoma involves the collection of 10-12 systematic biopsies (SBx) from both lobes. MRI-guided targeted biopsies (TBx) from suspicious foci increase the detection rates of clinically significant (cs) PCa. We investigated the extent to which the results of the TBx predicted the tumor board treatment decisions. SBx and TBx were acquired from 150 patients. Risk stratifications and recommendations for interventional therapy (prostatectomy and radiotherapy) or active surveillance were established by interdisciplinary tumor boards. We analyzed how often TBx alone were enough to correctly classify the tumors as well as to indicate interventional therapy and how often the findings of SBx were crucial for therapy decisions. A total of 28/39 (72%) favorable risk tumors were detected in TBx, of which 11/26 (42%) very-low-risk tumors were not detected and 8/13 (62%) low-risk tumors were undergraded. A total of 36/44 (82%) intermediate-risk PCa were present in TBx, of which 4 (9%) were underdiagnosed as a favorable risk tumor. A total of 12/13 (92%) high-risk carcinomas were detected and correctly grouped in TBx. The majority of csPCa were identified by the sampling of TBx alone. The tumor size was underestimated in a proportion of ISUP grade 1 tumors. Systematic biopsy sampling is therefore indicated for the next AS follow-up in these cases.

Initial Quality of Life and Toxicity Analysis of a Randomized Phase 3 Study of Moderately Hypofractionated Radiation Therapy With or Without Androgen Suppression for Intermediate-Risk Adenocarcinoma of the Prostate: PCG GU003

Purpose

Our objective was to report the quality of life (QoL) analysis and toxicity in patients with intermediate-risk prostate cancer treated with or without androgen deprivation therapy (ADT) in Proton Collaborative Group (PCG) GU003.

Methods and Materials

Between 2012 and 2019, patients with intermediate-risk prostate cancer were enrolled. Patients were randomized to receive moderately hypofractionated proton beam therapy (PBT) to 70 Gy relative biologic effectiveness in 28 fractions to the prostate with or without 6 months of ADT. Expanded Prostate Cancer Index Composite, Short-Form 12, and the American Urological Association Symptom Index instruments were given at baseline and 3, 6, 12, 18, and 24 months after PBT. Toxicities were assessed according to Common Terminology Criteria for Adverse Events (version 4).

Results

One hundred ten patients were randomized to PBT either with 6 months of ADT (n = 55) or without ADT (n = 55). The median follow-up was 32.4 months (range, 5.5-84.6). On average, 101 out of 110 (92%) patients filled out baseline QoL and patient-reported outcome surveys. The compliance was 84%, 82%, 64%, and 42% at 3, 6, 12, and 24 months, respectively. Baseline median American Urological Association Symptom Index was comparable between arms (6 [11%] ADT vs 5 [9%] no ADT, P = .359). Acute and late grade 2+ genitourinary and gastrointestinal toxicity were similar between arms. The ADT arm experienced a QoL decline of mean scores in the sexual (-16.1, P < .001) and hormonal (-6.3, P < .001) domains, with the largest time-specific hormonal differences at 3 (-13.8, P < .001) and 6 (-11.2, P < .001) months. The hormonal QoL domain returned to baseline 6 months after therapy. There was a trend to baseline in sexual function 6 months after completion of ADT.

Conclusions

After 6 months of ADT, sexual and hormonal domains returned to baseline 6 months after completion of treatment for men with intermediate-risk prostate cancer.

Expanding the role of PSMA PET in active surveillance

INTRODUCTION

Accurate grading at the time of diagnosis is fundamental to risk stratification and treatment decision making, particularly for men being considered for Active Surveillance (AS). With the introduction of prostate-specific membrane antigen (PSMA) positron emission tomography (PET) there has been considerable improvement in sensitivity and specificity for the detection and staging of clinically significant prostate cancer. Our study aims to determine the role of PSMA PET/CT in men with newly diagnosed low or favourable intermediate risk prostate cancer to better select men for AS.

METHOD

This is a retrospective single centre study performed from January 2019 and October 2022. This study includes men identified from electronic medical record system who had undergone a PSMA PET/CT following newly diagnosed low or favourable-intermediate risk prostate cancer. Primary outcome was to assess the change in management for men being considered for AS following PSMA PET/CT results on the basis of PSMA PET characteristics.

RESULTS

In total, there were 11 of 30 men (36.67%) who were assigned management by AS and 19 of 30 men (63.33%) who had definitive treatment. 15 of the 19 men that needed treatment had concerning features on PSMA PET/CT results. Of the 15 men with concerning features on PSMA PET, 9 (60%) men were found to have adverse pathological features on final prostatectomy features.

CONCLUSION

This retrospective study suggests that PSMA PET/CT has potential to influence the management of men with newly diagnosed prostate cancer that would otherwise be appropriate for active surveillance.

Intermediate-risk Prostate Cancer-A Sheep in Wolf's Clothing?

This case-based discussion describes a 65-year-old man newly diagnosed with International Society of Urological Pathology (ISUP) grade 2 prostate cancer (PCa). According to the European Association of Urology classification system, the patient harbors an intermediate-risk cancer. In step-by step discussion, we elaborate guideline-based treatment modalities for intermediate-risk PCa focused on debating active surveillance versus active treatment. Thereby, we discuss the importance of patient characteristics, including age, hereditary factors, life expectancy and comorbidity status, findings of multiparametric magnetic resonance imaging, as well as prostate-specific antigen (PSA) density and PSA kinetics, in predicting the clinical course of the disease. In addition, we focus on cribriform pathology as a predictor of adverse outcomes and critically discuss its relevance in patient management. Lastly, we outline genomic stratification in ISUP 2 cancer as a future tool to predict PCa aggressiveness. PATIENT SUMMARY: Based on current guidelines, patients with intermediate-risk prostate cancer are treated actively or can alternatively undergo an active surveillance approach when favorable risk factors are present. One major issue is to discriminate between patients who benefit from an active therapy approach and those who benefit from a deferred treatment. Therefore, reliable biomarkers and early predictors of disease progression are needed urgently.

Low-volume grade group 2 prostate cancer candidates for active surveillance: a radical prostatectomy retrospective analysis

OBJECTIVE

Guidelines support considering selected men with ISUP grade group (GG) 2 prostate cancer for active surveillance (AS). We assessed the association of clinical variables with unfavorable pathology at radical prostatectomy in low-volume GG 2 prostate cancer on biopsy in a retrospective cohort.

MATERIALS AND METHODS

This was a retrospective analysis of 378 men with low-volume (≤ 2 cores) GG 2 localized prostate cancer who underwent prostatectomy at a single tertiary cancer center. Multivariable logistic regression of unfavorable pathology, upgrading to ≥ T3, or GG ≥ 3 was performed in relation to clinical factors, common variables used in AS in GG 1 and percentage Gleason 4 at biopsy. We compared the performance of potential variables with commonly used combined AS restrictions in GG 1 prostate cancer.

RESULTS

In total, 128/378 (34%) men had unfavorable pathology at radical prostatectomy. On multivariable analysis, > 5% Gleason pattern 4 was independently associated with an increased risk of GG ≥ 3. A maximum percentage core involvement > 50% was independently associated with an increased risk of pT-stage ≥ 3 and unfavorable pathology. Restriction to patients with ≤ 5% Gleason 4 decreased the upgrading of both unfavorable pathology (OR = 0.62, p = 0.041) and GG ≥ 3 (OR = 0.17, p = 0.0007) compared to the full cohort, while restriction to those with ≤ 50% of max core involvement did not.

CONCLUSION

In low-volume GG 2, the percentage of Gleason 4 of ≤ 5% was the strongest predictor in reducing upgrading at final pathology. This easily available pathological descriptor could be used to guide urologists and patients when considering AS in this setting.

Full functional-length urethral sphincter- and neurovascular bundle preservation improves long-term continence rates after robotic-assisted radical prostatectomy

The objective of the study was to test the impact of implementing standard full functional-length urethral sphincter (FFLU) and neurovascular bundle preservation (NVBP) with intraoperative frozen section technique (IFT) on long-term urinary continence in patients undergoing robotic-assisted radical prostatectomy (RARP). We relied on an institutional tertiary-care database to identify patients who underwent RARP between 01/2014 and 09/2019. Until 10/2017, FFLU was not performed and decision for NVBP was taken without IFT. From 11/2017, FFLU and IFT-guided NVBP was routinely performed in all patients undergoing RARP. Long-term continence (≥ 12 months) was defined as the usage of no or one safety- pad. Uni- and multivariable logistic regression models tested the correlation between surgical approach (standard vs FFLU + NVBP) and long-term continence. Covariates consisted of age, body mass index, prostate volume and extraprostatic extension of tumor. The study cohort consisted of 142 patients, with equally sized groups for standard vs FFLU + NVBP RARP (68 vs 74 patients). Routine FFLU + NVBP implementation resulted in a long-term continence rate of 91%, compared to 63% in standard RARP (p < 0.001). Following FFLU + NVBP RARP, 5% needed 1-2, 4% 3-5 pads/24 h and no patient (0%) suffered severe long-term incontinence (> 5 pads/24 h). No significant differences in patient or tumor characteristics were recorded between both groups. In multivariable logistic regression models, FFLU + NVBP was a robust predictor for continence (Odds ratio [OR]: 7.62; 95% CI 2.51-27.36; p < 0.001). Implementation of FFLU and NVBP in patients undergoing RARP results in improved long-term continence rates of 91%.

Urinary Outcomes After Magnetic Resonance Imaging-Guided Whole-Gland Transurethral Ultrasound Ablation for Prostate Cancer: Comparison of Suprapubic Tube to Indwelling Urethral Catheter

Background: MRI-guided transurethral ultrasound ablation (TULSA) is under investigation for whole-gland ablation of low- and intermediate-risk prostate cancer. The ideal method for post-TULSA bladder drainage through postoperative suprapubic tube (SPT) vs indwelling urethral catheter (UC) has not been established. The objective of this study was to evaluate urinary outcomes after whole-gland TULSA, comparing postoperative SPT with UC. Materials and Methods: Two-institution retrospective analysis of whole-gland TULSA for men with grade group 1 and 2 prostate cancer. One institution placed SPT at the time of TULSA with clamp trials (day 10) and removal once voiding. The second placed UC until void trial (day 7). Outcomes included the International Prostate Symptom Score (IPSS), urinary bother score, catheter reinsertion, stricture, clean intermittent catheterization (CIC), and incontinence. Results: Forty-five patients (median age 67) were analyzed. The UC cohort (N = 26) was older (p = 0.007) than the SPT cohort (N = 19) but with similar baseline prostate volumes, IPSS, and urinary bother scores. Patients receiving UC had fewer days with catheter (p = 0.013). Although UC patients suffered more lower urinary tract symptoms at 1-month post-TULSA, there was no significant difference between IPSS scores at baseline and 6 months after surgery regardless of urinary management strategy, although the UC group noted significantly decreased urinary bother. Rates of infection were similar between groups. Six strictures were observed overall, with more in the SPT group, although the difference was not significant (4/19 [21.1%] SPT; 2/26 [7.7%] UC). At 6 months, incontinence rates were low and similar between groups (2/19 [10.5%] SPT; 4/26 [15.4%] UC) and only one patient (UC) required CIC. Conclusions: Our overall findings suggest that SPT and UC are both acceptable options for postoperative bladder drainage after whole-gland TULSA, with statistically similar rates of urinary complications but a slightly different side effect profile.

Trends and variation in the use of radiotherapy in non-metastatic prostate cancer: A 12-year nationwide overview from the Netherlands

PURPOSE

This population-based study describes nationwide trends and variation in the use of primary radiotherapy for non-metastatic prostate cancer in The Netherlands in 2008-2019.

METHODS

Prostate cancer patients were selected from the Netherlands Cancer Registry (N = 103,059). Treatment trends were studied over time by prognostic risk groups. Multilevel analyses were applied to identify variables associated with external beam radiotherapy (EBRT) and brachy-monotherapy versus no active treatment in low-risk disease, and EBRT versus radical prostatectomy in intermediate and high-risk disease.

RESULTS

EBRT use remained stable (5-6%) in low-risk prostate cancer and increased from 21% to 32% in intermediate-risk, 37% to 45% in high-risk localized and 50% to 57% in high-risk locally advanced disease. Brachy-monotherapy decreased from 19% to 6% and from 15% to 10% in low and intermediate-risk disease, respectively, coinciding an increase of no active treatment from 55% to 73% in low-risk disease. Use of EBRT or brachy-monotherapy versus no active treatment in low-risk disease differed by region, T-stage and patient characteristics. Hospital characteristics were not associated with treatment in low-risk disease, except for availability of brachy-monotherapy in 2008-2013. Age, number of comorbidities, travel time for EBRT, prognostic risk group, and hospital characteristics were associated with EBRT versus prostatectomy in intermediate and high-risk disease.

CONCLUSION

Intermediate/high-risk PCa was increasingly managed with EBRT, while brachy-monotherapy in low/intermediate-risk PCa decreased. In low-risk PCa, the no active treatment-approach increased. Variation in treatment suggests treatment decision related to patient/disease characteristics. In intermediate/high-risk disease, variation seems furthermore related to the treatment modalities available in the diagnosing hospitals.

Colorectal Cancer Survival Prediction Using Deep Distribution Based Multiple-Instance Learning

Most deep-learning algorithms that use Hematoxylin- and Eosin-stained whole slide images (WSIs) to predict cancer survival incorporate image patches either with the highest scores or a combination of both the highest and lowest scores. In this study, we hypothesize that incorporating wholistic patch information can predict colorectal cancer (CRC) cancer survival more accurately. As such, we developed a distribution-based multiple-instance survival learning algorithm (DeepDisMISL) to validate this hypothesis on two large international CRC WSIs datasets called MCO CRC and TCGA COAD-READ. Our results suggest that combining patches that are scored based on percentile distributions together with the patches that are scored as highest and lowest drastically improves the performance of CRC survival prediction. Including multiple neighborhood instances around each selected distribution location (e.g., percentiles) could further improve the prediction. DeepDisMISL demonstrated superior predictive ability compared to other recently published, state-of-the-art algorithms. Furthermore, DeepDisMISL is interpretable and can assist clinicians in understanding the relationship between cancer morphological phenotypes and a patient's cancer survival risk.

Improving the stratification of intermediate risk prostate cancer

BACKGROUND

Intermediate risk prostate cancer (IR PCa) may exhibit a wide array of phenotypes, from favorable to unfavorable. NCCN criteria help distinguishing between favorable versus unfavorable subgroups. We studied and attempted to improve this classification.

METHODS

Within the SEER database 2010-2016, we identified 19,193 IR PCa patients treated with radical prostatectomy. A multivariable logistic regression model predicting unfavorable IR PCa was developed and externally validated, in addition to a head-to-head comparison with NCCN IR PCa stratification.

RESULTS

Model development (development cohort N.=13,436: 3585 unfavorable versus 9851 favorable) rested on age, PSA, clinical T stage, biopsy Gleason Grade Group (GGG) and percentage of positive cores. All were independent predictors of unfavorable IR PCa. In external validation cohort (N.=5757: 1652 unfavorable versus 4105 favorable), NCCN stratification was 61.8% accurate in discriminating between favorable versus unfavorable, compared to 67.6% for nomogram, which exhibited excellent calibration, less pronounced departures from ideal prediction and greater net-benefit in decision curve analyses (DCA) than NCCN stratification. The optimal nomogram cutoff misclassified 312 of 1976 patients (15.8%) versus 598 of 2877 (20.8%) for NCCN stratification. Of NCCN misclassified patients, 90.0% harbored pT3-4 stages versus 84.6% of nomogram.

CONCLUSIONS

The newly developed, externally validated nomogram discriminates better between favorable versus unfavorable IR PCa, according to overall accuracy, calibration, DCA, and actual numbers and stage distribution of misclassified patients.

m6A Methylation Regulators Are Predictive Biomarkers for Tumour Metastasis in Prostate Cancer

Simple Summary

Recurrence and metastatic progression always lead to dismal outcomes in prostate cancer (PCa). There is no reliable biomarker for the prediction of recurrence and metastasis other than the Prostate Cancer Antigen (PCA). N6-methyladenosine (m⁶A) is the most common post-transcriptional mRNA modification and is regulated by m⁶A regulators dynamically. Since m⁶A modification is associated with cancer development and outgrowth, we performed a consensus clustering on PCa with regard to the gene expression of all m⁶A regulators. We identified three subtypes of Pca with distinct m⁶A expression patterns and enriched biological pathways. We also established an m⁶A score for metastasis prediction based on our clustering, which is potentially a predictive biomarker for Pca metastasis.

Abstract

Prostate cancer (PCa) is one of the most common cancers in men. Usually, most PCas at initial diagnosis are localized and hormone-dependent, and grow slowly. Patients with localized PCas have a nearly 100% 5-year survival rate; however, the 5-year survival rate of metastatic or progressive PCa is still dismal. N6-methyladenosine (m⁶A) is the most common post-transcriptional mRNA modification and is dynamically regulated by m⁶A regulators. A few studies have shown that the abnormal expression of m⁶A regulators is significantly associated with cancer progression and immune cell infiltration, but the roles of these regulators in PCa remain unclear. Here, we examined the expression profiles and methylation levels of 21 m⁶A regulators across the Cancer Genome Atlas (TCGA), 495 PCas by consensus clustering, and correlated the expression of m⁶A regulators with PCa progression and immune cell infiltration. Consensus clustering was applied for subtyping Pca samples into clusters based on the expression profiles of m⁶A regulators. Each subtype’s signature genes were obtained by a pairwise differential expression analysis. Featured pathways of m⁶A subtypes were predicted by Gene Ontology. The m⁶A score was developed to predict m⁶A activation. The association of the m⁶A score with patients’ survival, metastasis and immune cell infiltration was also investigated. We identified three distinct clusters in PCa based on the expression profiles of 21 m⁶A regulators by consensus clustering. The differential expression and pathway analyses on the three clusters uncovered the m⁶A regulators involved in metabolic processes and immune responses in PCa. Moreover, we developed an m⁶A score to evaluate the m⁶A regulator activation for PCa. The m⁶A score is significantly associated with Gleason scores and metastasis in PCa. The predictive capacity of the m⁶A score on PCa metastasis was also validated in another independent cohort with an area under the curve of 89.5%. Hence, our study revealed the critical role of m⁶A regulators in PCa progression and the m⁶A score is a promising predictive biomarker for PCa metastasis.

Direct comparison of low-dose-rate brachytherapy versus radical prostatectomy using the surgical definition of biochemical recurrence for patients with intermediate-risk prostate cancer

Background

We compared the oncological outcomes of patients who received seed brachytherapy (SEED-BT) with those who received radical prostatectomy (RP) for intermediate-risk prostate cancer.

Methods

Candidates were patients treated with either SEED-BT (n = 933) or RP (n = 334). One-to-one propensity score matching was performed to adjust the patients’ backgrounds. We compared the biochemical recurrence (BCR)-free rate using the Phoenix definition (prostate-specific antigen [PSA] nadir plus 2 ng/mL) for SEED-BT and the surgical definition (PSA cut-off value of 0.2 ng/mL) for RP. We also directly compared the BCR-free rates using the same PSA cut-off value of 0.2 ng/mL for both SEED-BT and RP.

Results

In the propensity score-matched analysis with 214 pairs, the median follow-up treatment was 96 months (range 1–158 months). Fifty-three patients (24.7%) were treated with combined SEED-BT and external-beam radiotherapy. Forty-three patients (20.0%) received salvage radiotherapy after RP. Comparing the BCR-free rate using the above definitions for SEED-BT and RP showed that SEED-BT yielded a significantly better 8-year BCR-free rate than did RP (87.4% vs. 74.3%, hazard ratio [HR] 0.420, 95% confidence interval [CI] 0.273–0.647). Comparing the 8-year BCR-free rate using the surgical definition for both treatments showed no significant difference between the two treatments (76.7% vs. 74.3%, HR 0.913, 95% CI 0.621–1.341). SEED-BT had a significantly better 8-year salvage hormonal therapy-free rate than did RP (92.0% vs. 85.6%, HR 0.528, 95% CI 0.296–0.942, P = 0.030). The 8-year metastasis-free survival rates (98.5% vs. 99.0%, HR 1.382, 95% CI 0.313–6.083, P = 0.668) and overall survival rates (91.9% vs. 94.6%, HR 1.353, 95% CI 0.690–2.650) did not significantly differ between the treatments.

Conclusions

The BCR-free rates did not significantly differ between patients treated with SEED-BT and those treated with RP for intermediate-risk prostate cancer even when they were directly compared using the surgical definition for BCR. SEED-BT and RP can be adequately compared for oncological outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02046-x.

Metastasis and Mortality in Men With Low- and Intermediate-Risk Prostate Cancer on Active Surveillance

BACKGROUND

Active surveillance (AS) is a safe treatment option for men with low-risk, localized prostate cancer. However, the safety of AS for patients with intermediate-risk prostate cancer remains unclear.

PATIENTS AND METHODS

We identified men with NCCN-classified low-risk and favorable and unfavorable intermediate-risk prostate cancer diagnosed between 2001 and 2015 and initially managed with AS in the Veterans Health Administration. We analyzed progression to definitive treatment, metastasis, prostate cancer-specific mortality (PCSM), and all-cause mortality using cumulative incidences and multivariable competing-risks regression.

RESULTS

The cohort included 9,733 men, of whom 1,007 (10.3%) had intermediate-risk disease (773 [76.8%] favorable, 234 [23.2%] unfavorable), followed for a median of 7.6 years. The 10-year cumulative incidence of metastasis was significantly higher for patients with favorable (9.6%; 95% CI, 7.1%-12.5%; P<.001) and unfavorable intermediate-risk disease (19.2%; 95% CI, 13.4%-25.9%; P<.001) than for those with low-risk disease (1.5%; 95% CI, 1.2%-1.9%). The 10-year cumulative incidence of PCSM was also significantly higher for patients with favorable (3.7%; 95% CI, 2.3%-5.7%; P<.001) and unfavorable intermediate-risk disease (11.8%; 95% CI, 6.8%-18.4%; P<.001) than for those with low-risk disease (1.1%; 95% CI, 0.8%-1.4%). In multivariable competing-risks regression, favorable and unfavorable intermediate-risk patients had significantly increased risks of metastasis and PCSM compared with low-risk patients (all P<.001).

CONCLUSIONS

Compared with low-risk patients, those with favorable and unfavorable intermediate-risk prostate cancer managed with AS are at increased risk of metastasis and PCSM. AS may be an appropriate option for carefully selected patients with favorable intermediate-risk prostate cancer, though identification of appropriate candidates and AS protocols should be tested in future prospective studies.

Prevalence of adverse pathology features in grade group 2 prostatectomy specimens with syn- or metachronous metastatic disease

BACKGROUND

To validate the importance of recently established adverse histopathology features (cribriform pattern and intraductal carcinoma) as contra-indication for deferred treatment of Gleason score 7 (3 + 4) (grade group [GG] 2) prostate cancer, we investigated their frequency in GG2 radical prostatectomies with syn- or metachronous metastatic disease.

METHODS

GG2 prostatectomy specimens of patients with concomitant lymph node metastasis or distant metastasis at follow-up were identified in a clinical database of a tertiary care center and their pathology was reviewed for pathological stage, lymphovascular invasion, Gleason grade 4 subpatterns, presence of tertiary grade 5, and ductal adenocarcinoma histology. A control group of 99 GG2 prostatectomy specimens who had no metastatic disease (controls) was reviewed for the same adverse pathological features.

RESULTS

Of 1860 GG2 prostatectomy specimens (operated between 2002 and 2020), 45 (2.4%) had concurrent regional lymph node metastases or distant metastases at follow-up. Pathological stage distribution of cases and controls was 24% and 79% pT2, 42% and 15% pT3a, 33% and 6.1% pT3b -T4, respectively (p < 0.001). Eleven of 45 cases (24%) had ≤10% Gleason grade 4 component. Cribriform pattern or intraductal carcinoma was present in 84% of cases versus 34% of controls (p < 0.001), tertiary grade 5 in 16% of cases versus 5% controls (p = 0.05) and ductal adenocarcinoma in 16% of cases versus 2% of controls (p = 0.004). Among the seven cases without cribriform or intraductal carcinoma, two displayed ductal adenocarcinoma features.

CONCLUSIONS

Well-established unfavorable histopathologic features (intraductal and cribriform pattern carcinoma, ductal adenocarcinoma) are represented in about 90% of GG2 prostate cancers with local or distant metastatic disease and are much less common (38%) in those without metastatic disease. Strikingly, about 25% of GG2 prostatectomy cases with metastatic disease had an organ-confined disease and/or a small percentage of Gleason grade 4 pattern. This further emphasizes the relative importance of these adverse histopathological features (cribriform, intraductal, and ductal adenocarcinoma) rather than percentage Gleason grade 4 as contra-indicator of deferred treatment for patients with GG2 prostate cancer.

MiR-378a inhibits glucose metabolism by suppressing GLUT1 in prostate cancer

Prostate cancer (PCa) is the fifth leading cause of cancer related deaths worldwide, in part due to a lack of molecular stratification tools that can distinguish primary tumours that will remain indolent from those that will metastasise. Amongst potential molecular biomarkers, microRNAs (miRs) have attracted particular interest because of their high stability in body fluids and fixed tissues. These small non-coding RNAs modulate several physiological and pathological processes, including cancer progression. Herein we explore the prognostic potential and the functional role of miRs in localised PCa and their relation to nodal metastasis. We define a 7-miR signature that is associated with poor survival independently of age, Gleason score, pathological T state, N stage and surgical margin status and that is also prognostic for disease-free survival in patients with intermediate-risk localised disease. Within our 7-miR signature, we show that miR-378a-3p (hereafter miR-378a) levels are low in primary tumours compared to benign prostate tissue, and also lower in Gleason score 8-9 compared to Gleason 6-7 PCa. We demonstrate that miR-378a impairs glucose metabolism and reduces proliferation in PCa cells through independent mechanisms, and we identify glucose transporter 1 (GLUT1) messenger RNA as a direct target of miR-378a. We show that GLUT1 inhibition hampers glycolysis, leading to cell death. Our data provides a rational for a new PCa stratification strategy based on miR expression, and it reveals that miR-378a and GLUT1 are potential therapeutic targets in highly aggressive glycolytic PCa.

Up- and downgrading in single intermediate-risk positive biopsy core prostate cancer

Background

Up- and/or downgrading rates in single intermediate-risk positive biopsy core are unknown.

Methods

We identified single intermediate-risk (Gleason grade group (GGG) 2/GGG3) positive biopsy core prostate cancer patients (≤ cT2c and PSA ≤ 20 ng/mL) within the Surveillance, Epidemiology, and End Results (SEER) database (2010–2015). Subsequently, separate uni- and multivariable logistic regression models tested for independent predictors of up- and downgrading.

Results

Of 1,328 assessable patients with single core positive intermediate-risk prostate cancer at biopsy, 972 (73%) harbored GGG2 versus 356 (27%) harbored GGG3. Median PSA (5.5 vs 5.7; p = 0.3), median age (62 vs 63 years; p = 0.07) and cT1-stage (77 vs 75%; p = 0.3) did not differ between GGG2 and GGG3 patients. Of individuals with single GGG2 positive biopsy core, 191 (20%) showed downgrading to GGG1 versus 35 (4%) upgrading to GGG4 or GGG5 at RP. Of individuals with single GGG3 positive biopsy core, 36 (10%) showed downgrading to GGG1 versus 42 (12%) significant upgrading to GGG4 or GGG5 at RP. In multivariable logistic regression models, elevated PSA (10–20 ng/mL) was an independent predictor of upgrading to GGG4/GGG5 in single GGG3 positive biopsy core patients (OR:2.89; 95%-CI: 1.31–6.11; p = 0.007).

Conclusion

In single GGG2 positive biopsy core patients, downgrading was four times more often recorded compared to upgrading. Conversely, in single GGG3 positive biopsy core patients, up- and downgrading rates were comparable and should be expected in one out of ten patients.

Comparative performance of MRI-derived PRECISE scores and delta-radiomics models for the prediction of prostate cancer progression in patients on active surveillance

OBJECTIVES

To compare the performance of the PRECISE scoring system against several MRI-derived delta-radiomics models for predicting histopathological prostate cancer (PCa) progression in patients on active surveillance (AS).

METHODS

The study included AS patients with biopsy-proven PCa with a minimum follow-up of 2 years and at least one repeat targeted biopsy. Histopathological progression was defined as grade group progression from diagnostic biopsy. The control group included patients with both radiologically and histopathologically stable disease. PRECISE scores were applied prospectively by four uro-radiologists with 5-16 years' experience. T2WI- and ADC-derived delta-radiomics features were computed using baseline and latest available MRI scans, with the predictive modelling performed using the parenclitic networks (PN), least absolute shrinkage and selection operator (LASSO) logistic regression, and random forests (RF) algorithms. Standard measures of discrimination and areas under the ROC curve (AUCs) were calculated, with AUCs compared using DeLong's test.

RESULTS

The study included 64 patients (27 progressors and 37 non-progressors) with a median follow-up of 46 months. PRECISE scores had the highest specificity (94.7%) and positive predictive value (90.9%), whilst RF had the highest sensitivity (92.6%) and negative predictive value (92.6%) for predicting disease progression. The AUC for PRECISE (84.4%) was non-significantly higher than AUCs of 81.5%, 78.0%, and 80.9% for PN, LASSO regression, and RF, respectively (p = 0.64, 0.43, and 0.57, respectively). No significant differences were observed between AUCs of the three delta-radiomics models (p-value range 0.34-0.77).

CONCLUSIONS

PRECISE and delta-radiomics models achieved comparably good performance for predicting PCa progression in AS patients.

KEY POINTS

• The observed high specificity and PPV of PRECISE are complemented by the high sensitivity and NPV of delta-radiomics, suggesting a possible synergy between the two image assessment approaches. • The comparable performance of delta-radiomics to PRECISE scores applied by expert readers highlights the prospective use of the former as an objective and standardisable quantitative tool for MRI-guided AS follow-up. • The marginally superior performance of parenclitic networks compared to conventional machine learning algorithms warrants its further use in radiomics research.

Influence of Biopsy Gleason Score on the Risk of Lymph Node Invasion in Patients With Intermediate-Risk Prostate Cancer Undergoing Radical Prostatectomy

Objective: To analyze the influence of biopsy Gleason score on the risk for lymph node invasion (LNI) during pelvic lymph node dissection (PLND) in patients undergoing radical prostatectomy (RP) for intermediate-risk prostate cancer (PCa).

Materials and Methods: We retrospectively analyzed 684 patients, who underwent RP between 2014 and June 2020 due to PCa. Univariable and multivariable logistic regression, as well as binary regression tree models were used to assess the risk of positive LNI and evaluate the need of PLND in men with intermediate-risk PCa.

Results: Of the 672 eligible patients with RP, 80 (11.9%) men harbored low-risk, 32 (4.8%) intermediate-risk with international society of urologic pathologists grade (ISUP) 1 (IR-ISUP1), 215 (32.0%) intermediate-risk with ISUP 2 (IR-ISUP2), 99 (14.7%) intermediate-risk with ISUP 3 (IR-ISUP3), and 246 (36.6%) high-risk PCa. Proportions of LNI were 0, 3.1, 3.7, 5.1, and 24.0% for low-risk, IR-ISUP1, IR-ISUP 2, IR-ISUP-3, and high-risk PCa, respectively (p < 0.001). In multivariable analyses, after adjustment for patient and surgical characteristics, IR-ISUP1 [hazard ratio (HR) 0.10, p = 0.03], IR-ISUP2 (HR 0.09, p < 0.001), and IR-ISUP3 (HR 0.18, p < 0.001) were independent predictors for lower risk of LNI, compared with men with high-risk PCa disease.

Conclusions: The international society of urologic pathologists grade significantly influence the risk of LNI in patients with intermediate- risk PCa. The risk of LNI only exceeds 5% in men with IR-ISUP3 PCa. In consequence, the need for PLND in selected patients with IR-ISUP 1 or IR-ISUP2 PCa should be critically discussed.

The impact of receptor of advanced glycation end-products polymorphisms on prostate cancer progression and clinicopathological characteristics

The receptor for advanced glycation end products (RAGE) overexpression was suggested to be associated with prostate cancer development and poor prognosis. In this study, we focused on the correlations between the clinicopathological characteristics and susceptibility of prostate cancer and RAGE single-nucleotide polymorphisms (SNPs). In 579 prostate cancer patients, the RAGE SNPs rs1800625, rs1800624, rs2070600 and rs184003 in patients with or without grade group upgrade were analysed with real-time polymerase chain reaction. The results demonstrated that the prostate cancer patients who carried the RAGE SNPs rs2070600 'GA' genotypic variants were significantly associated with lower risk to develop grade group upgrade. Moreover, patients with the RAGE rs1800625 'TC + CC' genotypic variants were associated with higher risk of perineural invasion. In 343 prostate cancer patients who carried the RAGE rs1800625 'TC + CC' genotype without grade group upgrade were correlated with higher risk of biochemical recurrence and perineural invasion. In the analysis of TCGA database, significant differences of the RAGE mRNA level were found between the normal controls and prostate cancer patients (p < 0.0001), and the pathologic stage N1 and N0 patients (p = 0.0027). The prostate cancer patients with high RAGE expression were associated with lower overall survival rate (p = 0.025). In conclusion, our results have revealed that the RAGE SNPs rs2070600 and rs1800625 were associated with the grade group upgrade of prostate cancer and clinical status. The RAGE polymorphisms may provide as a pivotal predictor to evaluate prostate cancer disease progression and prognosis.

The impact of race/ethnicity on upstaging and/or upgrading rates among intermediate risk prostate cancer patients treated with radical prostatectomy

BACKGROUND

Race/ethnicity may predispose to less favorable prostate cancer characteristics in intermediate risk prostate cancer (IR PCa) patients. We tested this hypothesis in a subgroup of IR PCa patients treated with radical prostatectomy (RP).

METHODS

We relied on the Surveillance, Epidemiology and End Results 2004-2016. The effect of race/ethnicity was tested in univariable and multivariable logistic regression analyses predicting upstaging (pT3+/pN1) and/or upgrading (Gleason Grade Group [GGG] 4-5) at RP.

RESULTS

Of 20,391 IR PCa patients, 15,050 (73.8%) were Caucasian, 2857 (14.0%) African-American, 1632 (8.0%) Hispanic/Latino and 852 (4.2%) Asian. Asian patients exhibited highest age (64 year), highest PSA (6.8 ng/ml) and highest rate of GGG3 (31.9%). African-Americans exhibited the highest percentage of positive cores at biopsy (41.7%) and the highest proportion of NCCN unfavorable risk group membership (54.6%). Conversely, Caucasians exhibited the highest proportion of cT2 stage (35.6%). In univariable analyses, Hispanic/Latinos exhibited the highest rates of upstaging/upgrading among all race/ethnicities, in both favorable and unfavorable groups, followed by Asians, Caucasians and African-Americans in that order. In multivariable analyses, Hispanic/Latino race/ethnicity represented an independent predictor of higher upstaging and/or upgrading in favorable IR PCa (odds ratio [OR] 1.27, p < 0.01), while African-American race/ethnicity represented an independent predictor of lower upstaging and/or upgrading in unfavorable IR PCa (OR 0.79, p < 0.001).

CONCLUSION

Race/ethnicity predisposes to differences in clinical, as well as in pathological characteristics in IR PCa patients. Specifically, even after full statistical adjustment, Hispanic/Latinos are at higher and African-Americans are at lower risk of upstaging and/or upgrading.

Risk Stratification of Patients Candidate to Radical Prostatectomy Based on Clinical and Multiparametric Magnetic Resonance Imaging Parameters: Development and External Validation of Novel Risk Groups

BACKGROUND

Despite the key importance of magnetic resonance imaging (MRI) parameters, risk classification systems for biochemical recurrence (BCR) in prostate cancer (PCa) patients treated with radical prostatectomy (RP) are still based on clinical variables alone.

OBJECTIVE

We aimed at developing and validating a novel classification integrating clinical and radiological parameters.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective multicenter cohort study was conducted between 2014 and 2020 across seven academic international referral centers. A total of 2565 patients treated with RP for PCa were identified.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Early BCR was defined as two prostate-specific antigen (PSA) values of ≥0.2 ng/ml within 3 yr after RP. Kaplan-Meier and Cox regressions tested time and predictors of BCR. Development and validation cohorts were generated from the overall patient sample. A model predicting early BCR based on Cox-derived coefficients represented the basis for a nomogram that was validated externally. Predictors consisted of PSA, biopsy grade group, MRI stage, and the maximum diameter of lesion at MRI. Novel risk categories were then identified. The Harrel's concordance index (c-index) compared the accuracy of our risk stratification with the European Association of Urology (EAU), Cancer of the Prostate Risk Assessment (CAPRA), and International Staging Collaboration for Cancer of the Prostate (STAR-CAP) risk groups in predicting early BCR.

RESULTS AND LIMITATIONS

Overall, 200 (8%), 1834 (71%), and 531 (21%) had low-, intermediate-, and high-risk disease according to the EAU risk groups. The 3-yr overall BCR-free survival rate was 84%. No differences were observed in the 3-yr BCR-free survival between EAU low- and intermediate-risk groups (88% vs 87%; p = 0.1). The novel nomogram depicted optimal discrimination at external validation (c-index 78%). Four new risk categories were identified based on the predictors included in the Cox-based nomogram. This new risk classification had higher accuracy in predicting early BCR (c-index 70%) than the EAU, CAPRA, and STAR-CAP risk classifications (c-index 64%, 63%, and 67%, respectively).

CONCLUSIONS

We developed and externally validated four novel categories based on clinical and radiological parameters to predict early BCR. This novel classification exhibited higher accuracy than the available tools.

PATIENT SUMMARY

Our novel and straightforward risk classification outperformed currently available preoperative risk tools and should, therefore, assist physicians in preoperative counseling of men candidate to radical treatment for prostate cancer.

Regional differences in patient age and prostate cancer characteristics and rates of treatment modalities in favorable and unfavorable intermediate risk prostate cancer across United States SEER registries

BACKGROUND

Intermediate risk (IR) prostate cancer (PCa) is a highly heterogeneous entity and can be distinguished into favorable and unfavorable IR PCa according to biopsy, PSA and cT-stage characteristics. These differences may translate into differences in treatment type.

METHODS

We tested for differences in PCa tumor characteristics and differences in active treatment rates (radical prostatectomy [RP], external beam radiotherapy [EBRT]) according to Surveillance, Epidemiology and End Results (SEER) registry (2010-2015) in favorable and unfavorable IR PCa. Data were stratified according to individual SEER registries. Further analyses additionally adjusted for PCa baseline characteristics (PSA, cT stage, biopsy Gleason group grading [GGG], percentage of positive biopsy cores).

RESULTS

Tabulations according to SEER registries showed that, in favorable IR vs. unfavorable IR, the rates of RP and EBRT respectively ranged from 30.0 to 54.3% vs. 30.3-55.5 % and 8.3-44.7 % vs. 11.5-45.5 %. Differences in age and baseline PCa tumor characteristics also existed in both favorable and unfavorable IR across SEER registries. After adjustment for those baseline patient and PCa characteristics (PSA, cT stage, GGG, percentage of positive biopsy cores), RP and EBRT rates exhibited virtually no residual differences across individual SEER registries, in both favorable (36.0-41.0 % and 26.8-28.1 %) and unfavorable IR PCa (39.2-42.0% and 31.1-33.5 %).

CONCLUSION

Important differences may be identified in treatment rates within the examined 18 SEER registries in favorable and in unfavorable IR PCa. However, the observed differences are virtually entirely explained by differences in baseline PCa characteristics.

Short Androgen Suppression and Radiation Dose Escalation in Prostate Cancer: 12-Year Results of EORTC Trial 22991 in Patients With Localized Intermediate-Risk Disease

PURPOSE

The European Organisation for Research and Treatment of Cancer (EORTC) trial 22991 (NCT00021450) showed that 6 months of concomitant and adjuvant androgen suppression (AS) improves event- (EFS, Phoenix) and clinical disease-free survival (DFS) of intermediate- and high-risk localized prostatic carcinoma, treated by external-beam radiotherapy (EBRT) at 70-78 Gy. We report the long-term results in intermediate-risk patients treated with 74 or 78 Gy EBRT, as per current guidelines.

PATIENT AND METHODS

Of 819 patients randomly assigned between EBRT or EBRT plus AS started on day 1 of EBRT, 481 entered with intermediate risk (International Union Against Cancer TNM 1997 cT1b-c or T2a with prostate-specific antigen (PSA) ≥ 10 ng/mL or Gleason ≤ 7 and PSA ≤ 20 ng/mL, N0M0) and had EBRT planned at 74 (342 patients, 71.1%) or 78 Gy (139 patients, 28.9%). We report the trial primary end point EFS, DFS, distant metastasis-free survival (DMFS), and overall survival (OS) by intention-to-treat stratified by EBRT dose at two-sided α = 5%.

RESULTS

At a median follow-up of 12.2 years, 92 of 245 patients and 132 of 236 had EFS events in the EBRT plus AS and EBRT arm, respectively, mostly PSA relapse (48.7%) or death (45.1%). EBRT plus AS improved EFS and DFS (hazard ratio [HR] = 0.53; CI, 0.41 to 0.70; P < .001 and HR = 0.67; CI, 0.49 to 0.90; P = .008). At 10 years, DMFS was 79.3% (CI, 73.4 to 84.0) with EBRT plus AS and 72.7% (CI, 66.2 to 78.2) with EBRT (HR = 0.74; CI, 0.53 to 1.02; P = .065). With 140 deaths (EBRT plus AS: 64; EBRT: 76), 10-year OS was 80.0% (CI, 74.1 to 84.7) with EBRT plus AS and 74.3% (CI, 67.8 to 79.7) with EBRT, but not statistically significantly different (HR = 0.74; CI, 0.53 to 1.04; P = .082).

CONCLUSION

Six months of concomitant and adjuvant AS statistically significantly improves EFS and DFS in intermediate-risk prostatic carcinoma, treated by irradiation at 74 or 78 Gy. The effects on OS and DMFS did not reach statistical significance.

Active surveillance for prostate cancer

Many men diagnosed with localized prostate cancer can postpone definitive treatment without raising their risk of metastasis or death from disease. Active surveillance (AS) is a method of monitoring select men, with the option of switching to active treatment upon signs of progression, thereby avoiding the well-known side-effects of surgery and radiotherapy. This review analyzes the data from long-running AS cohorts to determine the safety and efficacy of AS. We conducted a narrative review of recently published data, including 14 articles from 13 AS cohorts. The cohorts used varying inclusion criteria, with reported differences in clinical T stage and Gleason Score (Grade Group), among other features. Some studies (n=5) limited their cohorts to low-risk patients, while others (n=8) also included intermediate-risk patients. The heterogeneity of the cohorts produced mixed results, with the risk of prostate cancer metastasis ranging from 0.1–1.0% at 10 years and the risk of prostate cancer mortality ranging from 0–1.9% at 10 years. However, the majority of studies reported risks of less than 0.5% at 10 years for both metastasis and death. For most cohorts, half of men remained untreated for 5–10 years, with estimates ranging from 37% receiving active treatment in the Toronto cohort to 73% in the Prostate Cancer Research International AS (PRIAS) study. Current data do not support the use of negative magnetic resonance imaging (MRI) to avoid scheduled biopsy. Taken together, the data collected from these AS cohorts suggests that AS is a safe approach for men with low-grade prostate cancer and some men with intermediate risk disease. AS should be more broadly implemented for eligible patients to avoid the decreases in quality of life from undergoing active treatment. Studies expanding the inclusion criteria and further defining a subset of men with favorable intermediate-risk prostate cancer who might safely benefit from AS are needed to assess the long-term outcomes of using AS in intermediate-risk groups.

Impact of a Genomic Test on Treatment Decision in a Predominantly African American Population With Favorable-Risk Prostate Cancer: A Randomized Trial

PURPOSE

The Genomic Prostate Score (GPS), performed on biopsy tissue, predicts adverse outcome in prostate cancer (PCa) and has shown promise for improving patient selection for active surveillance (AS). However, its impact on treatment choice in high-risk populations of African Americans is largely unknown and, in general, the effect of the GPS on this difficult decision has not been evaluated in randomized trials.

METHODS

Two hundred men with National Comprehensive Cancer Network very low to low-intermediate PCa from three Chicago hospitals (70% Black, 16% college graduates) were randomly assigned at diagnosis to standard counseling with or without a 12-gene GPS assay. The primary end point was treatment choice at a second postdiagnosis visit. The proportion of patients choosing AS was compared, and multivariable modeling was used to estimate the effects of various factors on AS acceptance.

RESULTS

AS acceptance was high overall, although marginally lower in the intervention group (77% v 88%; P = .067), and lower still when men with inadequate specimens were excluded (P = .029). Men with lower health literacy who received a GPS were seven-fold less likely to choose AS compared with controls, whereas no difference was seen in men with higher health literacy (Pinteraction = .022). Among men with low-intermediate risk, 69% had GPS values consistent with unfavorable intermediate or high-risk cancer. AS choice was also independently associated with a family history of PCa and having health insurance.

CONCLUSION

In contrast to other studies, the net effect of the GPS was to move patients away from AS, primarily among men with low health literacy. These findings have implications for our understanding of how prognostic molecular assays that generate probabilities of poor outcome can affect treatment decisions in diverse clinical populations.

Low-/high-dose-rate brachytherapy boost in patients with intermediate-risk prostate cancer treated with radiotherapy: long-term results from a single institution team experience

Purpose

To compare brachytherapy (BT) boost of low-dose-rate (LDR) and high-dose-rate (HDR) techniques in patients diagnosed with intermediate-risk prostate cancer.

Material and methods

Between January 2005 and February 2018, 142 patients (50 LDR and 92 HDR) with intermediate-risk prostate cancer were treated with a BT boost, and retrospectively analyzed. Prescribed dose was 45 Gy with external beam radiotherapy (EBRT) plus 100-108 Gy with LDR-BT, and 60 Gy with EBRT plus one fraction of 10 Gy with HDR-BT. 99% of patients received androgen deprivation therapy (ADT) for 6 months. Primary endpoint was to compare LDR and HDR boosts in terms of biochemical progression-free survival (bPFS). Secondary endpoint, after re-classifying patients into "favorable" and "unfavorable" sub-groups, was to analyze differences with a similar treatment intensity.

Results

Median overall follow-up for the total cohort was 66.5 months (range, 16-185 months). There were no significant differences in bPFS, overall survival, cause specific survival, local failure, lymph node failure, or distant failure when LDR or HDR was employed. bPFS at 90 months was 100% for favorable, and 89% and 85% for unfavorable patients at 60 months and 90 months, respectively (log-rank test, p = 0.017). The crude incidence of genitourinary acute and chronic toxicity grade 3 was 0.7% and 4%, respectively. Twelve patients (8%) had chronic rectal hemorrhage grade 2, in whom argon was applied (4 LDR and 8 HDR).

Conclusions

Combined treatment is an excellent therapeutic option in patients with intermediate-risk prostate carcinoma, with similar results in both LDR and HDR approaches and very low toxicities. Importantly, the current literature has indicated that unfavorable-risk patients belong to a different category, and should be treated as patients with high-risk factors. Therefore, the stratification and identification of both risk groups is extremely relevant.

Population-Based Comparison of Different Risk Stratification Systems Among Prostate Cancer Patients

Background

It is not known which risk stratification system has the best discrimination ability for predicting prostate cancer death.

Methods

We identified patients with non-metastatic primary prostate adenocarcinoma diagnosis between 2004 and 2015 using the Surveillance, Epidemiology, and End Results database. Patients were categorized in different risk groups using the three frequently used risk stratification systems of the National Comprehensive Cancer Network guideline (NCCN-g), American Urological Association guideline (AUA-g), and European Association of Urology guideline (EAU-g), respectively. Associations between risk classification and prostate cancer-specific mortality (PCSM) were determined using Kaplan–Meier analyses and multivariable regression with Cox proportional hazards model. Area under the receiver operating characteristics curve (AUC) analyses were used to test the discrimination ability of the three risk grouping systems.

Results

We analyzed 310,062 patients with a median follow-up of 61 months. A total of 36,368 deaths occurred, including 6,033 prostate cancer deaths. For all the three risk stratification systems, the risk groups were significantly associated with PCSM. The AUC of the model relying on NCCN-g, AUA-g, and EAU-g risk stratification systems for PCSM at specifically 8 years were 0.818, 0.793, and 0.689 in the entire population; 0.819, 0.795, and 0.691 in Whites; 0.802, 0.777, and 0.681 in Blacks; 0.862, 0.818, and 0.714 in Asians; 0.845, 0.806, and 0.728 in Chinese patients. Regardless of the age, marital status, socioeconomic status, and treatment modality, AUC of the model relying on NCCN-g and AUA-g for PCSM was greater than that relying on EAU-g; AUC of the model relying on NCCN-g system was greater than that of the AUA-g system.

Conclusions

The NCCN-g and AUA-g risk stratification systems perform better in discriminating PCSM compared to the EAU-g system. The discrimination ability of the NCCN-g system was better than that of the AUA-g system. It is recommended to use NCCN-g to evaluate risk groups for prostate cancer patients and then provide more appropriate corresponding treatment recommendations.

A Phase 1 study Combining Pexidartinib, Radiation Therapy, and Androgen Deprivation Therapy in Men With Intermediate- and High-Risk Prostate Cancer

Purpose

This study aimed to evaluate a combination of radiation therapy (RT), androgen deprivation therapy (ADT), and pexidartinib (colony-stimulating factor 1 receptor [CSF1R]) inhibitor in men with intermediate- and high-risk prostate cancer. CSF1R signaling promotes tumor infiltration and survival of tumor-associated macrophages, which in turn promote progression and resistance. Counteracting protumorigenic actions of tumor-associated macrophages via CSF1R inhibition may enhance therapeutic efficacy of RT and ADT for prostate cancer.

Methods and Materials

In this phase 1 study, the treatment regimen consisted of pexidartinib (800 mg, administered as a split-dose twice daily) and ADT (both for a total of 6 months), and RT that was initiated at the start of month 3. RT volumes included the prostate and proximal seminal vesicles. The delivered dose was 7920 cGy (180 cGy per fraction) using intensity modulated RT with daily image guidance for prostate localization. The primary objective was to identify the maximum tolerated dose based on dose-limiting toxicities.

Results

All 4 enrolled patients who were eligible to receive RT had T₁ stage prostate cancer, 2 were intermediate risk, and 2 were high risk. The median age was 62.5 years, and the prostate-specific antigen levels were in the range 6.4 to 10.7 ng/mL. The patients’ individual Gleason scores were 3 + 3, 4 + 3, 4 + 4, and 4 + 5. All 4 patients reported ≥1 adverse events before RT. Grade 1 hypopigmentation was observed in 1 patient, and grade 3 pulmonary embolus in another. One patient experienced fatigue and joint pain, and another elevated amylase and pruritus (all grade 3 toxicities). Five of the 6 adverse events noted in 3 patients were all grade 3 toxicities attributable to pexidartinib, qualifying as dose-limiting toxicities and ultimately resulting in the study closure.

Conclusions

The combination was not well tolerated and does not warrant further investigation in men with intermediate- and high-risk prostate cancer.

MR-Guided High-Intensity Directional Ultrasound Ablation of Prostate Cancer

PURPOSE OF REVIEW

The goal of this paper was to review the novel treatment modality of high-intensity transurethral directional ultrasound for prostate cancer.

RECENT FINDINGS

Prostate cancer is a heterogeneous disease with some patients electing for active surveillance and focal therapies instead of definitive treatment with radical prostatectomy or radiation therapy. Prostate MRI has become a cornerstone of prostate cancer diagnosis, targeted biopsy, and treatment planning. Transurethral high-intensity directional ultrasound allows for MRI-guided ablation of the prostate gland with the ability to contour boundaries and spare critical structures, such as the neurovascular bundle and urinary sphincter. Although results are still emerging, this may offer patients a new option for focal therapy with a favorable side-effect profile. High-intensity transurethral directional ultrasound is an emerging treatment modality for both whole-gland and focal ablation with promising early results. Further research is needed to establish safety, tolerability, and long-term oncologic outcomes.

Grade group 2 (10% ≥ GP4) patients have very similar malignant potential with grade group 1 patients, given the risk of intraductal carcinoma of the prostate

BACKGROUND

It has been argued that grade group 2 (GG2) with a low Gleason pattern 4 (GP4) proportion should be an indication for active surveillance (AS) of prostate cancer (PCa). However, the cut-off GP4 proportion for AS remains unclear. Here, we evaluated the effect of GP4 proportion and IDC-P on cancer recurrence following radical prostatectomy (RP) in GG1 and GG2 patients, and identified candidates for AS.

METHODS

We retrospectively evaluated 646 patients with PCa who underwent RP between 2005 and 2014, and whose specimens were of GG1 or GG2 status.

RESULTS

The GGs were as follows: GG1, 25.2% (n = 163); GG2 (5% ≥ GP4), 11.4% (n = 74); GG2 (5% < GP4 ≤ 10%), 25.9% (n = 167); and GG2 (20% ≤ GP4), 37.5% (n = 242). IDC-P was detected in 26 patients (4%), i.e., in 2/167 GG2 (5% < GP4 ≤ 10%; 1%) cases and 24/242 GG2 (20% ≤ GP4; 10%) cases. GG2 patients with IDC-P exhibited a significantly poorer prognosis than did those without IDC-P (P < 0.0001), as did GG2 (20% ≤ GP4) patients without IDC-P (P < 0.05). The GG2 (5% ≥ GP4) and (5% < GP4 ≤ 10%) groups exhibited prognoses similar to those of the GG1 patients. In multivariate analysis, GG2 (20% ≤ GP4) without IDC-P, the presence of IDC-P, and the prostate-specific antigen level at diagnosis significantly predicted prognosis (P < 0.05, < 0.0001, and < 0.0001, respectively).

CONCLUSION

Our findings suggest that GG2 (GP4 ≤ 10%) patients could be indicated for AS, similar to GG1 patients, given the risk of IDC-P tumors.

Impact of Treating Physician on Radiation Therapy Related Severe Toxicities in Men with Prostate Cancer

PURPOSE

The impact of treating physician on radiation therapy (RT) related toxicity is unclear. We carried out a secondary analysis of a randomized controlled study to determine whether the risk of RT-related late toxicities in patients with prostate cancer varies depending on the treating radiation oncologist.

METHODS AND MATERIALS

This is a secondary analysis of a phase 3 randomized controlled study in which patients with prostate cancer with Gleason score ≤7, clinical stage T1b-T3a, and prostate-specific antigen <30 ng/mL were randomized to receive androgen suppression for 6 months, starting either 4 months before or concurrently with definitive prostate radiation therapy. Incidence of late RT-related toxicity was estimated using Kaplan-Meier methods. We applied multivariable semiparametric shared frailty models with gamma distribution to determine the between-physician variation in the hazard of late RT-related grade ≥3 gastrointestinal, genitourinary, or overall toxicity. Patient level covariables included age, risk group, year of enrollment, and treatment regimen. Frailty variance, a measure of unexplained heterogeneity, was estimated with 95% confidence intervals (CIs). Statistical significance was suggested when the lower limit of the 95% CI for the frailty variance was >0. The Commenges-Andersen test was used for P value estimation.

RESULTS

Overall, 426 patients were treated by 9 radiation oncologists. On log-rank test, there was a significant difference in the cumulative incidence of overall grade ≥3 toxicities (P = .001) and grade ≥3 gastrointestinal toxicity (P = .01) among the physician-based clusters. The frailty variance for overall late grade ≥3 toxicity was 0.31 (95% CI, 0.02-1.39; P = .01). The frailty variance for the grade ≥3 gastrointestinal and genitourinary toxicity was 0.84 (95% CI, 0.00-4.20; P = .11) and 0.11 (95% CI, 0.00-1.13; P = .31), respectively.

CONCLUSIONS

In our study, the hazard of overall RT-related late grade ≥3 toxicity varied significantly depending on treating radiation oncologist. Further studies are required to explore the underlying processes that lead to such variations in clinical trials involving radiation therapy in prostate cancer.

Stratifying patients with intermediate-risk prostate cancer: Validation of a new model based on MRI parameters and targeted biopsy and comparison with NCCN and AUA subclassifications

OBJECTIVE

Intermediate-risk prostate cancer regroups heterogeneous patients with different oncologic outcomes. Aim of the study is to validate a novel intermediate-risk subclassification ("magnetic resonance imaging [MRI] subclassification") that defines favorable and unfavorable diseases based on multiparametric MRI parameters and compare it to NCCN and AUA intermediate-risk subclassifications.

METHODS

A total of 429 patients treated with radical prostatectomy for NCCN intermediate-risk prostate cancer were identified. Using MRI subclassification, a favorable disease was defined as an organ-confined disease on MRI and international society of urological pathology Grade Group 1 to 2 on targeted biopsy. Remaining was classified as unfavorable. Univariable and multivariable analysis tested MRI subclassification in predicting overall unfavorable disease (OUD: pT3-4 and/or pN1 and/or International Society of Urological Pathology Grade Group ≥ 3), the need for adjuvant therapy and early biochemical recurrence (eBCR). Performance of NCCN, AUA, and MRI models was compared in term of OUD proportion and eBCR prediction using Harrell's c-index, calibrations plots, and decision curve analysis.

RESULTS

Median (interquartile range) follow-up was 12 months (4-28). In multivariable analysis, MRI subclassification was an independent factor for OUD (odds ratio [OR]: 4.54 [2.85-7.22], P < 0.001), the need for adjuvant therapy (OR: 3.42 [1.36-8.57], P = 0.009), and eBCR (HR: 2.62 [1.18-5.83], P = 0.018). Using this model, the proportion of unfavorable disease decreased from 73.7% and 63.9% to 35.9% (P < 0.001) associated to an increasing proportion of OUD when compared to NCCN and AUA models (63.9% and 67.1%-77.9% respectively, P < 0.001). Performance of the 3 models for eBCR prediction tended to be similar with a poor accuracy ranged from 58.7% to 66.7% (P > 0.05), permanent miscalibration and a net benefit at decision curve analysis.

CONCLUSIONS

We validated an intermediate-risk subclassification based on MRI and targeted biopsy that potentially improves patient selection by reducing the number of patients considered at unfavorable risk while increasing proportion of patients harboring poor oncologic outcomes. Its performance for eBCR detection was comparable to NCCN and AUA models.