African-specific molecular taxonomy of prostate cancer.

Prostate cancer is characterized by considerable geo-ethnic disparity. African ancestry is a significant risk factor, with mortality rates across sub-Saharan Africa of 2.7-fold higher than global averages1. The contributing genetic and non-genetic factors, and associated mutational processes, are unknown2,3. Here, through whole-genome sequencing of treatment-naive prostate cancer samples from 183 ancestrally (African versus European) and globally distinct patients, we generate a large cancer genomics resource for sub-Saharan Africa, identifying around 2 million somatic variants. Significant African-ancestry-specific findings include an elevated tumour mutational burden, increased percentage of genome alteration, a greater number of predicted damaging mutations and a higher total of mutational signatures, and the driver genes NCOA2, STK19, DDX11L1, PCAT1 and SETBP1. Examining all somatic mutational types, we describe a molecular taxonomy for prostate cancer differentiated by ancestry and defined as global mutational subtypes (GMS). By further including Chinese Asian data, we confirm that GMS-B (copy-number gain) and GMS-D (mutationally noisy) are specific to African populations, GMS-A (mutationally quiet) is universal (all ethnicities) and the African-European-restricted subtype GMS-C (copy-number losses) predicts poor clinical outcomes. In addition to the clinical benefit of including individuals of African ancestry, our GMS subtypes reveal different evolutionary trajectories and mutational processes suggesting that both common genetic and environmental factors contribute to the disparity between ethnicities. Analogous to gene-environment interaction-defined here as a different effect of an environmental surrounding in people with different ancestries or vice versa-we anticipate that GMS subtypes act as a proxy for intrinsic and extrinsic mutational processes in cancers, promoting global inclusion in landmark studies.

Prostate-specific membrane antigen positron emission tomography in addition to multiparametric magnetic resonance imaging and biopsies to select prostate cancer patients for focal therapy.

OBJECTIVE: To evaluate the additional value of prostate-specific membrane antigen positron emission tomography (PSMA-PET) to conventional diagnostic tools to select patients for hemi-ablative focal therapy (FT). PATIENTS AND METHODS: We performed a retrospective analysis on a multicentre cohort (private and institutional) of 138 patients who underwent multiparametric magnetic resonance imaging (mpMRI), PSMA-PET, and systematic biopsies prior to radical prostatectomy between January 2011 and July 2021. Patients were eligible when they met the consensus criteria for FT: PSA <15 ng/mL, clinical/radiological T stage ≤T2b, and International Society of Urological Pathology (ISUP) grade 2-3. Clinically significant prostate cancer (csPCa) was defined as ISUP grade ≥2, extracapsular extension >0.5 mm or seminal vesicle involvement at final histopathology. The diagnostic accuracy of mpMRI, systematic biopsies and PSMA-PET for csPCa (separate and combined) was calculated within a four-quadrant prostate model by receiver-operating characteristic and 2 × 2 contingency analysis. Additionally, we assessed whether the diagnostic tools correctly identified patients suitable for hemi-ablative FT. RESULTS: In total 552 prostate quadrants were analysed and 272 (49%) contained csPCa on final histopathology. The area under the curve, sensitivity, specificity, positive predictive value and negative predictive value for csPCa were 0.79, 75%, 83%, 81% and 77%, respectively, for combined mpMRI and systematic biopsies, and improved after addition of PSMA-PET to 0.84, 87%, 80%, 81% and 86%, respectively (P < 0.001). On final histopathology 46/138 patients (33%) were not suitable for hemi-ablative FT. Addition of PSMA-PET correctly identified 26/46 (57%) non-suitable patients and resulted in 4/138 (3%) false-positive exclusions. CONCLUSIONS: Addition of PSMA-PET to the conventional work-up by mpMRI and systematic biopsies could improve selection for hemi-ablative FT and guide exclusion of patients for whom whole-gland treatments might be a more suitable treatment option.

Median 4-year outcomes of salvage irreversible electroporation for localized radio-recurrent prostate cancer.

OBJECTIVES: To evaluate the safety, and short to mid-term oncological and quality-of-life (QoL) outcomes of focal irreversible electroporation (IRE) for radio-recurrent prostate cancer (PCa) at a median follow-up of 4 years. PATIENTS AND METHODS: This was a single-centre series of men with biopsy-proven radio-recurrent PCa treated with IRE between December 2013 and February 2022, with a minimum follow-up of 6 months. Follow-up included magnetic resonance imaging at 6 months, and standard transperineal saturation template biopsies at 12 months. Further biopsies were guided by suspicion on serial imaging or prostate-specific antigen (PSA) levels. Validated questionnaires were used to measure functional outcomes. Significant local recurrence was defined as any International Society of Urological Pathology (ISUP) score ≥ 2 on biopsies. Progression-free survival was defined as no signs of local or systemic disease on either imaging or template biopsies, or according to the Phoenix criteria for biochemical recurrence. RESULTS: Final analysis was performed on 74 men with radio-recurrent PCa (median age 69 years, median PSA level 5.4 ng/mL, 76% ISUP score 2/3). The median (range) follow-up was 48 (27-68) months. One rectal fistula occurred, and eight patients developed urethral sloughing that resolved with transurethral resection. Among patients who returned questionnaires (30/74, 41%), 93% (28/30) had preserved urinary continence and 23% (7/30) had sustained erectile function at 12-month follow-up. Local control was achieved in 57 patients (77%), who needed no further treatment. Biopsy diagnosed 41(55%) patients received follow up template biopsies, in-field recurrences occurred in 7% (3/41), and out-field recurrences occurred in 15% of patients (6/41). The metastasis-free survival rate was 91% (67/74), with a median (interquartile range) time to metastases of 8 (5-27) months. The Kaplan-Meier estimated 5-year progression-free survival rate was 60%. CONCLUSIONS: These short- to mid-term safety, oncological and QoL outcome data endorse results from smaller series and show the ability of salvage focal IRE to safely achieve oncological control in patients with radio-recurrent PCa.

Median 5-year outcomes of primary focal irreversible electroporation for localised prostate cancer.

OBJECTIVES: To evaluate longer-term oncological and functional outcomes of focal irreversible electroporation (IRE) as primary treatment for localised clinically significant prostate cancer (csPCa) at a median follow-up of 5 years (up to 10 years). PATIENTS AND METHODS: All patients that underwent focal IRE as primary treatment for localised PCa between February 2013 and August 2021 with a minimum 12 months of follow-up were analysed. Follow-up included 6-month magnetic resonance imaging (MRI) and standardised transperineal saturation template ± targeted biopsies at 12 months, and further biopsies in the case of clinical suspicion on serial imaging and/or prostate-specific antigen (PSA) levels. Failure-free survival (FFS) was defined as no progression to radical treatment or nodal/distant disease. Local recurrence was defined as any International Society of Urological Pathology Grade of ≥2 on biopsy. RESULTS: A total of 229 patients were analysed with a median (interquartile range [IQR]) follow-up of 60 (40-80) months. The median (IQR) age was 68 (64-74) years, the median (IQR) PSA level was 5.9 (4.1-8.2) ng/mL, and 86% harboured intermediate-risk disease and 7% high-risk disease. In all, 38 patients progressed to radical treatment (17%), at a median (IQR) of 35 (17-53) months after IRE. Kaplan-Meier FFS rates were 91% at 3 years, 84% at 5 years and 69% at 8 years. Metastasis-free survival was 99.6% (228/229), PCa-specific and overall survival were 100% (229/229). Residual csPCa was found in 24% (45/190) during follow-up biopsy and MRI showed a complete ablation in 82% (186/226). Short-term urinary continence was preserved (98%, three of 144 at baseline, 99%, one of 131 at 12 months) and erections sufficient for intercourse decreased by 13% compared to baseline (71% to 58%). CONCLUSION: Longer-term follow-up confirms our earlier findings that focal IRE provides acceptable local and distant oncological control in selected men with less urinary and sexual toxicity than radical treatment. Long-term follow-up and external validation of these findings, is required to establish this new treatment paradigm as a valid treatment option.

Salvage irreversible electroporation for radio-recurrent prostate cancer - the prospective FIRE trial.

OBJECTIVES: To prospectively assess the safety, functional- and oncological-outcomes of irreversible electroporation (IRE) as salvage therapy for radio-recurrent focal prostate cancer in a multicenter setting. PATIENTS AND METHODS: Men with focal recurrent PCa after external beam radiation or brachytherapy without metastatic disease on staging imaging and co-registration between mpMRI and biopsies were prospectively included in this multicenter trial. Adverse events were reported following the Clavien-Dindo classification. Validated questionnaires were used for patient-reported functional outcomes. Follow-up consisted of 3 monthly prostate specific antigen (PSA) levels, a 6-month mpMRI and standardised transperineal template mapping biopsies at 12-months. Thereafter follow-up was guided by MRI and/or PSMA-PET/CT and PSA. Local recurrence was defined as any ISUP score ≥2 on biopsies. RESULTS: 37 patients were analysed with a median (interquartile range (IQR)) follow up of 29 (22-43) months. Median age was 71 (53-83), median PSA was 3.5 ng/mL (2.7-6.1). 28 (75.5%) patients harboured intermediate risk and 9 patients (24.5%) high risk PCa. Seven patients (19%) reported self-limiting urgency, frequency, or hematuria (grade 1-2). Seven patients (19%) developed a grade 3 AE; urethral sludge requiring transurethral resection. At 12 months post treatment 93% of patients remained continent and erectile function sufficient for intercourse deteriorated from 35% to 15% (4/27). Local control was achieved in 29 patients (78%) and 27 patients (73%) were clear of local and systemic disease. Four (11%) patients had local recurrence only. Six (16%) patients developed metastatic disease with a median time to metastasis of 8 months. CONCLUSION: The FIRE trial shows that salvage IRE after failed radiation therapy for localised PCa is safe with minimal toxicity, and promising functional and oncological outcomes. Salvage IRE can offer a possible solution for notoriously difficult to manage radio recurrent prostate tumours.

Synchronous vs independent reading of prostate-specific membrane antigen positron emission tomography (PSMA-PET) and magnetic resonance imaging (MRI) to improve diagnosis of prostate cancer.

OBJECTIVES: To identify whether synchronous reading of multiparametric magnetic resonance imaging (mpMRI) and 68 Ga-PSMA-11 positron emission tomography (PET)/computed tomography (prostate-specific membrane antigen [PSMA-PET]) images can improve diagnostic performance and certainty compared with mpMRI/PSMA-PET reported independently and synthesized, while also assessing concordance between imaging modalities and agreement with histopathology. METHODS: This was a retrospective analysis of 100 patients randomly selected from the PRIMARY trial, a prospective Phase II multicentre imaging trial. Three dual-trained radiologist/nuclear medicine physicians re-reported the mpMRI and PSMA-PET both independently and synchronously for the same patients in random order, blinded to previous results. Diagnostic performance was assessed for mpMRI/PSMA-PET images read synchronously or independently and then synthesized. Agreement between imaging results and histopathology was examined. 'Concordance' between imaging modalities was defined as overlapping lesions. Reporting certainty was evaluated by the individual reporters for each modality. RESULTS: International Society of Urological Pathology Grade Group ≥2 cancer was present in 60% of patients on biopsy. Synchronous reading of mpMRI/PSMA-PET increased sensitivity compared to mpMRI or PSMA-PET alone (93% vs 80% vs 88%, respectively), although specificity was not improved (63% vs 58% vs 78%, respectively). No significant difference in diagnostic performance was noted between mpMRI/PSMA-PET read synchronously and mpMRI or PSMA-PET reported independently and then synthesized. Most patients had concordant imaging (60%), while others had discordant lesions only (28%) or a mixture (concordant and discordant lesions; 12%). When mpMRI/PSMA-PET findings were concordant and positive, 95% of patients had clinically significant prostate cancer (csPCa). When PSMA-PET alone was compared to synchronous PSMA-PET/MRI reads, there was an improvement in reader certainty in 20% of scans. CONCLUSION: Synchronous mpMRI/PSMA-PET reading improves reader certainty and sensitivity for csPCa compared to mpMRI or PSMA-PET alone. However, synthesizing the results of independently read PSMA-PET and mpMRI reports provided similar diagnostic performance to synchronous PSMA-PET/MRI reads. This may provide greater flexibility for urologists in terms of referral patterns, reducing healthcare system costs and improving efficiencies in prostate cancer diagnosis.

The relationship between biochemical recurrence and number of lymph nodes removed during surgery for localized prostate cancer.

PURPOSE: To assess whether completeness of pelvic lymph node dissection (PLND) as measured by lymph node yield reduces biochemical recurrence (BCR) in men undergoing radical prostatectomy (RP) for prostate cancer (PCa), stratified according to Briganti nomogram-derived risk (≥5% vs. < 5%) of lymph node invasion (LNI). METHODS: Retrospective study of 3724 men who underwent RP between January 1995 and January 2015 from our prospectively collected institutional database. All men included had minimum five years follow-up and were not given androgen deprivation therapy or radiotherapy prior to BCR. Primary endpoint was time to BCR as defined by PSA > 0.2ng/ml. Patients were analysed according to Briganti Nomogram derived risk of 'low-risk' (< 5%) vs. 'high-risk' (≥ 5%). Extent of PLND was analysed using number of nodes yielded at dissection as a continuous variable as well as a categorical variable: Group 1 (limited, 1-4 nodes), Group 2 (intermediate, 5-8 nodes) and Group 3(extensive, ≥9 nodes). RESULTS: Median follow-up in the overall cohort was 79.7 months and 65% of the total cohort underwent PLND. There were 2402 patients with Briganti risk of LNI < 5% and 1322 with a Briganti risk of LNI ≥5%. At multivariate analysis, only PSA (HR1.01, p < 0.001), extracapsular extension at RP (HR 1.86, p < 0.001), positive surgical margin (HR 1.61, p < 0.001) and positive lymph node on pathology (HR 1.52, p = 0.02) were independently associated with BCR. In the high-risk group, increased nodal yield at PLND was associated with reduction in risk of BCR (HR 0.97, 95%CI 0.95-1.00 p = 0.05, Cochran Mantel Haenszel test, p < 0.05: respectively). In the low-risk group increased number of nodes at PLND did not reduce risk of BCR. CONCLUSIONS: In this study of extent of PLND at RP, higher nodal yield did not reduce risk of BCR in low-risk men (Briganti risk < 5%), however there was a weak benefit in terms of reduced long-term risk of BCR in high-risk men (Briganti risk ≥5%).

Outcomes of salvage radical prostatectomy after initial irreversible electroporation treatment for recurrent prostate cancer.

OBJECTIVE: To evaluate: (i) safety, (ii) feasibility, and medium-term (iii) oncological and (iv) functional outcomes of salvage radical prostatectomy (sRP) for recurrent localised prostate cancer (PCa) following initial focal therapy using irreversible electroporation (IRE). PATIENTS AND METHODS: An international, multicentre and retrospective analysis of prospectively collected data of patients that underwent sRP for recurrent localised PCa after initial primary IRE treatment. Data were reported on (i) surgical complications, (ii) feasibility of sRP reported by surgeons, (iii) time interval between IRE and sRP and pathology results, and (iv) urinary continence, erectile function, and quality of life. RESULTS: In four participating centres, a total of 39 patients with a median (interquartile range [IQR]) age 64 (60-67) years were identified. No serious adverse events occurred during or following sRP and surgery was deemed feasible without difficulties. The median (IQR) time to recurrence following IRE was 14.3 (9.1-38.8) months. Pathology results showed localised disease in 21 patients (53.8%) and locally-advanced disease in 18 (46.2%). Positive surgical margins (PSMs) were observed in 10 patients (25.6%), of which six (15.4%) had significant PSMs. A persistent detectable prostate-specific antigen level was found in one case after sRP, caused by metastatic disease. One patient had a biochemical recurrence 6 months after sRP. These two cases, together with a PSM case, required additional therapy after sRP. After a median (IQR) follow-up of 17.7 (11.8-26.4) months, urinary continence and erectile function were preserved in 34 (94.4%) and 18 patients (52.9%), respectively, while quality of life remained stable. CONCLUSIONS: Salvage RP is safe and feasible for patients with recurrent localised PCa following initial IRE treatment. The medium-term oncological and functional outcomes are similar to primary RP. Strict patient selection for focal therapy and standardised follow-up is needed as some patients developed high-grade disease.

Salvage robot-assisted radical prostatectomy following focal ablation with irreversible electroporation: feasibility, oncological and functional outcomes.

BACKGROUND: To report the feasibility, oncological and functional outcomes of salvage robot-assisted radical prostatectomy (sRARP) for recurrent prostate cancer (PCa) after irreversible electroporation (IRE). METHODS: This was a retrospective analysis of patients who underwent sRARP by a single high-volume surgeon after IRE treatment in our institution. Surgical complications, oncological and functional outcomes were assessed. RESULTS: 15 patients with at least 12 months follow up were identified out of the 234 men who underwent primary IRE between 2013 and 2019. The median [IQR] age was 68 (62-70) years. The median [IQR] time from focal IRE to sRARP was 42 (21-57) months. There were no rectal, bladder or ureteric injuries. The T-stage was pT2 in 9 (60%) patients and pT3a in 6 (40%) patients. Only one (7%) patient had a positive surgical margin. At a median [IQR] follow up of 22 (16-32) months no patient had a biochemical recurrence (PSA > 0.2). All 15 patients were continent (pad-free) by 6 months and 9 (60%) patients had erections sufficient for intercourse with or without PDE5 inhibitors. No predisposing factors were identified for predicting erectile dysfunction after sRARP. CONCLUSIONS: In patients with recurrent or residual significant PCa after focal IRE ablation it is feasible to obtain good functional and oncological outcomes with sRARP. Our results demonstrate that good outcomes can be achieved with sRARP, when respecting close monitoring post-IRE, good patient selection and surgical experience. The limitations of this study are that it is a small series, with short follow up and a lack of standardised quality of life instruments.

Focal ablation of apical prostate cancer lesions with irreversible electroporation (IRE).

INTRODUCTION AND OBJECTIVE: To assess the safety, oncological and quality-of-life (QoL) outcomes of focal ablation of apical prostate cancer (PCa) lesions with irreversible electroporation (IRE). METHODS: Patients were included in the study if they had a PCa lesion within 3 mm of the apical capsule treated with IRE. The IRE procedure was performed in our institution by a single urologist. The QoL and functional data was collected prospectively from patients who provided consent using the Expanded Prostate Cancer Index Composite (EPIC). Oncological follow up included 3-month PSA levels, mpMRI at 6 months and transperineal biopsy at 1-year post treatment. RESULTS: A total of 50 patients had apical PCa lesions treated between February 2013 and September 2018. Median follow-up was 44 months. There were no Clavien-Dindo grade 3 events or higher. No perioperative complications were recorded. No significant difference was observed in the EPIC urinary or bowel QoL domain between baseline and 12-month post-treatment. One patient (2%) required one pad per day for urinary incontinence 12-month post-treatment. There was a small but significant decline in EPIC sexual QoL (65 at baseline and 59 at 12-month post-IRE). Of patient's potent pre-treatment, 94% remained potent after treatment. The median PSA nadir decreased by 71% (6.25-1.7 ng/mL). Only one patient (2.5%) had in-field residual disease on repeat biopsy. CONCLUSION: Focal ablation using IRE for PCa in the distal apex appears safe and feasible with acceptable early QoL and oncologic outcomes.

Irreversible electroporation (IRE): a narrative review of the development of IRE from the laboratory to a prostate cancer treatment.

INTRODUCTION: Whilst whole-gland radical treatment is highly effective for prostate cancer control, it has significant impact on quality of life and is unnecessary 'over-treatment' in many men with screening-detected prostate cancer. Improvements in prostate biopsy and imaging have led to increased interest in partial gland ablation to reduce treatment-related morbidity. Several energies for focal ablation have been trialled. Irreversible electroporation (IRE) is a novel technology that ablates tissue by delivering direct current between electrodes. This narrative review documents the history of electroporation including its scientific basis, early data from pre-clinical animal studies, and contemporary clinical outcomes from the use of IRE in prostate cancer. METHODS: A literature search using the Medical Literature Analysis and Retrieval System Online (MEDLINE), the Excerpta Medica dataBASE (EMBASE), PubMed and Google Scholar was undertaken to identify historical perspectives and current clinical data relating to IRE for prostate cancer. RESULTS: The history of electroporation and its implementation as a prostate cancer treatment was following the basic scientific principles, in vitro data, then animal studies, and now short- to medium-term clinical cohorts in humans. The results of IRE on >283 patients have been published in several papers, with preserved rates of (pad-free) continence in 91-100% of men and preserved erectile function in 79-100% of men. In-field recurrence rates range from 0% to 33%. The current state of evidence for IRE for the treatment of primary and salvage prostate cancer is considered as Idea, Development, Exploration, Assessment, Long-term follow-up (IDEAL) stage 2B. CONCLUSIONS: IRE is a new focal ablative technology for the treatment of localised prostate cancer in carefully selected men. Published cohorts report encouraging short-term oncological and functional outcomes; however, longer-term data are needed to validate this treatment before it can be recommended for widespread clinical use.

Use of gallium-68 prostate-specific membrane antigen positron-emission tomography for detecting lymph node metastases in primary and recurrent prostate cancer and location of recurrence after radical prostatectomy: an overview of the current literature.

OBJECTIVES: To review the literature to determine the sensitivity and specificity of gallium-68 prostate-specific membrane antigen (68 Ga-PSMA) positron-emission tomography (PET) for detecting pelvic lymph node metastases in patients with primary prostate cancer (PCa), and the positive predictive value in patients with biochemical recurrence (BCR) after initial curative treatment, and, in addition, to determine the detection rate and management impact of 68 Ga-PSMA PET in patients with BCR after radical prostatectomy (RP). MATERIALS AND METHODS: We performed a comprehensive literature search. Search terms used in MEDLINE, EMBASE and Science Direct were '(PSMA, 68 Ga-PSMA, 68 Gallium-PSMA, Ga-68-PSMA or prostate-specific membrane antigen)' and '(histology, lymph node, staging, sensitivity, specificity, positive predictive value, recurrence, recurrent or detection)'. Relevant abstracts were reviewed and full-text articles obtained where possible. References to and from obtained articles were searched to identify further relevant articles. RESULTS: Nine retrospective and two prospective studies described the sensitivity and specificity of 68 Ga-PSMA PET for detecting pelvic lymph node metastases before initial treatment, which ranged from 33.3% to 100% and 80% to 100%, respectively. In eight retrospective studies, the positive predictive value of 68 Ga-PSMA PET in patients with BCR before salvage lymph node dissection ranged from 70% to 100%. The detection rate of 68 Ga-PSMA PET in patients with BCR after RP in the PSA subgroups <0.2 ng/mL, 0.2-0.49 ng/mL and 0.5 to <1.0 ng/mL ranged from 11.3% to 50.0%, 20.0% to 72.7% and 25.0% to 87.5%, respectively. CONCLUSION: The review results showed that 68 Ga-PSMA PET had a high specificity for the detection of pelvic lymph node metastases in primary PCa. Furthermore, 68 Ga-PSMA PET had a very high positive predictive value in detecting lymph node metastases in patients with BCR. By contrast, sensitivity was only moderate; therefore, based on the currently available literature, 68 Ga-PSMA PET cannot yet replace pelvic lymph node dissection to exclude lymph node metastases. In the salvage phase, 68 Ga-PSMA PET had both a high detection rate and impact on radiotherapy planning in early BCR after RP.

Metagenomic analysis reveals a rich bacterial content in high-risk prostate tumors from African men.

BACKGROUND: Inflammation is a hallmark of prostate cancer (PCa), yet no pathogenic agent has been identified. Men from Africa are at increased risk for both aggressive prostate disease and infection. We hypothesize that pathogenic microbes may be contributing, at least in part, to high-risk PCa presentation within Africa and in turn the observed ethnic disparity. METHODS: Here we reveal through metagenomic analysis of host-derived whole-genome sequencing data, the microbial content within prostate tumor tissue from 22 men. What is unique about this study is that patients were separated by ethnicity, African vs European, and environments, Africa vs Australia. RESULTS: We identified 23 common bacterial genera between the African, Australian, and Chinese prostate tumor samples, while nonbacterial microbes were notably absent. While the most abundant genera across all samples included: Escherichia, Propionibacterium, and Pseudomonas, the core prostate tumor microbiota was enriched for Proteobacteria. We observed a significant increase in the richness of the bacterial communities within the African vs Australian samples (t = 4.6-5.5; P = .0004-.001), largely driven by eight predominant genera. Considering core human gut microbiota, African prostate tissue samples appear enriched for Escherichia and Acidovorax, with an abundance of Eubacterium associated with host tumor hypermutation. CONCLUSIONS: Our study provides suggestive evidence for the presence of a core, bacteria-rich, prostate microbiome. While unable to exclude for fecal contamination, the observed increased bacterial content and richness within the African vs non-African samples, together with elevated tumor mutational burden, suggests the possibility that bacterially-driven oncogenic transformation within the prostate microenvironment may be contributing to aggressive disease presentation in Africa.

p53 nuclear accumulation as an early indicator of lethal prostate cancer.

BACKGROUND: After radical prostatectomy (RP) for prostate cancer (PC), p53 alterations predict biochemical relapse (BCR), however, recent evidence suggests that metastatic relapse (MR) not BCR is a surrogate for PC specific mortality (PCSM). This updated analysis of a previously published study investigated the association between p53 aberrations, MR and PCSM in men with localised PC. METHODS: Two hundred and seventy-one men with localised PC treated with RP were included. RP specimens stained for p53 by immunohistochemistry were scored as (a) percentage of p53-positive tumour nuclei; and (b) clustering, where ≥12 p53-positive cells within a ×200 power field was deemed 'cluster positive'. Associations between p53 status and clinical outcomes (BCR, MR and PCSM) were evaluated. RESULTS: Increasing percentage of p53-positive nuclei was significantly associated with shorter time to BCR, MR and PCSM (All p < 0.001). Half of the patients were p53 cluster positive. p53 cluster positivity was significantly associated with poorer outcomes at all clinical endpoints (BCR: HR 2.0, 95% CI 1.51-2.65, p < 0.001; MR: HR 4.1, 95% CI 2.02-8.14, p < 0.001; PCSM: HR 12.2, 95% CI 1.6-93; p = 0.016). These associations were independent of other established prognostic variables. CONCLUSIONS: p53 aberrations in radical prostatectomy tissue predict clinically relevant endpoints of MR and PCSM.

Diagnostic accuracy of 68 Ga-prostate-specific membrane antigen (PSMA) positron-emission tomography (PET) and multiparametric (mp)MRI to detect intermediate-grade intra-prostatic prostate cancer using whole-mount pathology: impact of the addition of 68 Ga-PSMA PET to mpMRI.

OBJECTIVE: To evaluate the ability of prostate-specific membrane antigen (PSMA)-positron-emission tomography (PET)/computed tomography (CT) to detect intermediate-grade intra-prostatic prostate cancer (PCa), and to determine if PSMA-PET improves the diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI). PATIENTS AND METHODS: A total of 56 consecutive patients with International Society of Urological Pathology (ISUP) grade 2-3 PCa after radical prostatectomy, who underwent both mpMRI and PSMA-PET CT (hereafter PSMA-PET) preoperatively, were enrolled in this study. The accuracy of PSMA-PET, mpMRI alone, and the two procedures in combination was analysed for identifying ISUP grades 1-3 within a 12-segment model. The accuracy of a combined predictive model (PSMA-PET and mpMRI) was determined. Receiver-operating characteristic curve analysis to determine the optimal standardized uptake value (SUVmax ) for PSMA-PET in discriminating between ISUP grades 1 and ≥2 was performed. RESULTS: On a per-patient basis, the sensitivities for PSMA-PET and mpMRI in identifying ISUP grades 2-3 PCa were 100% and 97%, respectively. Assessing ISUP grade ≥2 PCa using a 12-segment analysis, PSMA-PET demonstrated greater diagnostic accuracy (area under the curve), sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV), with values of 0.91, 88%, 93%, 95% and 85%, respectively, than did mpMRI (Prostate Imaging Reporting and Data System [PI-RADS] 3-5), at 0.79, 68%, 91%, 87%, and 75%, respectively. When used in combination (PSMA-PET and mpMRI PIRADS 4-5), sensitivity, specificity, NPV and PPV were 92%, 90%, 96% and 81%, respectively. The sensitivity for both techniques reduced markedly when assessing ISUP grade 1 PCa (18% for PSMA-PET, 10% for mpMRI). An SUVmax value of 3.95 resulted in 94% sensitivity and 100% specificity. CONCLUSION: PSMA-PET is accurate in detecting segments containing intermediate-grade intra-prostatic PCa (ISUP grade ≥ 2), compared with and complementary to mpMRI. By contrast the detection rate for ISUP grade 1 disease for both PSMA-PET and mpMRI was low.

Effect of FAK inhibitor VS-6063 (defactinib) on docetaxel efficacy in prostate cancer.

BACKGROUND: Docetaxel, the standard chemotherapy for metastatic castration-resistant prostate cancer (CRPC) also enhances the survival of patients with metastatic castration-sensitive prostate cancer (CSPC) when combined with androgen-deprivation therapy. Focal Adhesion Kinase (FAK) activation is a mediator of docetaxel resistance in prostate cancer cells. The aim of this study was to investigate the effect of the second generation FAK inhibitor VS-6063 on docetaxel efficacy in pre-clinical CRPC and CSPC models. METHODS: Docetaxel-resistant CRPC cells, mice with PC3 xenografts, and ex vivo cultures of patient-derived primary prostate tumors were treated with VS-6063 and/or docetaxel, or vehicle control. Cell counting, immunoblotting, and immunohistochemistry techniques were used to evaluate the treatment effects. RESULTS: Docetaxel and VS-6063 co-treatment caused a greater decrease in the viability of docetaxel-resistant CRPC cells, and a greater inhibition in PC3 xenograft growth compared to either monotherapy. FAK expression in human primary prostate cancer was positively associated with advanced tumor stage. Patient-derived prostate tumor explants cultured with both docetaxel and VS-6063 displayed a higher percentage of apoptosis in cancer cells, than monotherapy treatment. CONCLUSIONS: Our findings suggest that co-administration of the FAK inhibitor, VS-6063, with docetaxel represents a potential therapeutic strategy to overcome docetaxel resistance in prostate cancer.

Altered mitochondrial genome content signals worse pathology and prognosis in prostate cancer.

BACKGROUND: Mitochondrial genome (mtDNA) content is depleted in many cancers. In prostate cancer, there is intra-glandular as well as inter-patient mtDNA copy number variation. In this study, we determine if mtDNA content can be used as a predictor for prostate cancer staging and outcomes. METHODS: Fresh prostate cancer biopsies from 115 patients were obtained at time of surgery. All cores underwent pathological review, followed by isolation of cancer and normal tissue. DNA was extracted and qPCR performed to quantify the total amount of mtDNA as a ratio to genomic DNA. Differences in mtDNA content were compared for prostate cancer pathology features and disease outcomes. RESULTS: We showed a significantly reduced mtDNA content in prostate cancer compared with normal adjacent prostate tissue (mean difference 1.73-fold, P-value <0.001). Prostate cancer with increased mtDNA content showed unfavorable pathologic characteristics including, higher disease stage (PT2 vs PT3 P-value = 0.018), extracapsular extension (P-value = 0.02) and a trend toward an increased Gleason score (P-value = 0.064). No significant association was observed between changes in mtDNA content and biochemical recurrence (median follow up of 107 months). CONCLUSIONS: Contrary to other cancer types, prostate cancer tissue shows no universally depleted mtDNA content. Rather, the change in mtDNA content is highly variable, mirroring known prostate cancer genome heterogeneity. Patients with high mtDNA content have an unfavorable pathology, while a high mtDNA content in normal adjacent prostate tissue is associated with worse prognosis.

Prostate cancer in 432 men aged <50 years in the prostate-specific antigen era: a new outlook.

OBJECTIVE: To evaluate the clinical presentation and treatment outcomes of prostate cancer (PCa) in 432 consecutive patients aged < 50 years in the prostate-specific antigen (PSA) era. METHODS: Retrospective analysis was performed on all patients with PCa (14 570) from the years 1994 to 2017. A total of 432 consecutive patients aged < 50 years were identified. The patients were stratified by D'Amico risk groups, and their clinical presentation and treatment outcomes were analysed. The rates of biochemical recurrence after surgery were compared with the D'Amico prediction model as well as with older propensity-score-matched patients. The surgical pathology results in patients undergoing active surveillance (AS) were compared with those of low-risk patients who underwent immediate surgery. RESULTS: A total of 44%, 42% and 13% of patients harboured low-risk, intermediate-risk and high-risk PCa, respectively. Their median age was 47 years and a positive family history of PCa was reported in 39.1%. Clinical stage was T1 in 65.5% and T2 in 30.0% of patients, and 2.0% of patients had metastatic disease at presentation. Radical prostatectomy (RP) was performed in 78.4% of patients (n = 339) and the biochemical recurrence rates were 7.8% (low-risk), 15.3% (intermediate-risk) and 23.3% (high-risk) at 5 years post-surgery. These rates were lower than expected according to the D'Amico prediction model or when compared with older matched patients. A total of 74 patients with low-risk PCa underwent AS and only 17.6% (n = 13) required radical treatment after a median follow-up of 46 months. The surgical pathology results in patients undergoing ASdid not differ significantly from patients with low-risk PCa who underwent immediate surgery (positive surgical margins [P = 0.145], tumour volume [P = 0.257] or seminal vesicle involvement [P = 0.100]). Of the present cohort, only 0.4% died from PCa during a median follow-up of 65 months. CONCLUSIONS: The clinical presentation and prognosis of young patients has changed dramatically during the PSA era. Patients nowadays present with lower-risk disease that can be treated adequately, with reassuring biochemical recurrence rates at 5 years post-surgery. AS appears to be safe in patients with low-risk. PCa.

Focal irreversible electroporation as primary treatment for localized prostate cancer.

OBJECTIVES: To determine the safety, quality of life (QoL) and short-term oncological outcomes of primary focal irreversible electroporation (IRE) for the treatment of localized prostate cancer (PCa), and to identify potential risk factors for oncological failure. PATIENTS AND METHODS: Patients who met the consensus guidelines on patient criteria and selection methods for primary focal therapy were eligible for analysis. Focal IRE was performed for organ-confined clinically significant PCa, defined as high-volume disease with Gleason sum score 6 (International Society of Urological Pathology [ISUP] grade 1) or any Gleason sum score of 7 (ISUP grades 2-3). Oncological, adverse event (AE) and QoL outcome data, with a minimum of 6 months' follow-up, were analysed. Patient characteristics and peri-operative treatment variables were compared between patients with and without oncological failure on follow-up biopsy. Wilcoxon's signed rank test, Wilcoxon's rank sum test and the chi-squared test were used to assess statistically significant differences in paired continuous, unpaired continuous and categorical variables respectively. RESULTS: A total of 63 patients met all eligibility criteria and were included in the final analysis. No high-grade AEs occurred. QoL questionnaire analysis demonstrated no significant change from baseline in physical (P = 0.81), mental (P = 0.48), bowel (P = 0.25) or urinary QoL domains (P = 0.41 and P = 0.25), but there was a mild decrease in the sexual QoL domain (median score 66 at baseline vs 54 at 6 months; P < 0.001). Compared with baseline, a decline of 70% in prostate-specific antigen level (1.8 ng/mL, interquartile range 0.96-4.8 ng/mL) was seen at 6-12 months. A narrow safety margin (P = 0.047) and system errors (P = 0.010) were identified as potential early risk factors for in-field oncological failure. In-field and whole-gland oncological control on follow-up biopsies was 84% (38/45 patients) and 76% (34/45 patients); this increased to 97% (38/39 patients) and 87% (34/39 patients) when patients treated with a narrow safety margin and system errors were excluded. CONCLUSION: Our data support the safety and feasibility of focal IRE as a primary treatment for localized PCa with effective short-term oncological control in carefully selected men.