Daniel Christidis

Sensitivity, Specificity, and Predictors of Positive 68Ga–Prostate-specific Membrane Antigen Positron Emission Tomography in Advanced Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT Positron emission tomography (PET) of 68Ga-labelled prostate-specific membrane antigen (68Ga-PSMA) is an emerging imaging modality introduced to assess the burden of prostate cancer, typically in biochemically recurrent or advanced disease. 68Ga-PSMA PET provides the ability to selectively identify and localize metastatic prostate cancer cells and subsequently change patient management. Owing to its limited history, robust sensitivity and specificity data are not available for 68Ga-PSMA PET-positive scans. OBJECTIVE A systematic review and meta-analysis of reported predictors of positive 68Ga-PSMA PET and corresponding sensitivity and specificity profiles. EVIDENCE ACQUISITION We performed critical reviews of MEDLINE, EMBASE, ScienceDirect, Cochrane Library, and Web of Science databases in April 2016 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Quality was assessed using the Quality Assessment if Diagnostic Accuracy Studies-2 tool. Meta-analysis and meta-regression of proportions were performed using a random-effects model with pre-PET prostate-specific antigen (PSA) levels as the dependent variable. Summary sensitivity and specificity values were obtained by fitting bivariate hierarchical regression models. EVIDENCE SYNTHESIS Sixteen articles involving 1309 patients were analysed. The overall percentage of positive 68Ga-PSMA PET among patients was 40% (95% confidence interval [CI] 19-64%) for primary staging and 76% (95% CI 66-85%) for biochemical recurrence (BCR). Positive 68Ga-PSMA PET scans for BCR patients increased with pre-PET PSA. For the PSA categories 0-0.2, 0.2-1, 1-2, and >2 ng/ml, 42%, 58%, 76%, and 95% scans, respectively, were positive. Shorter PSA doubling time increased 68Ga-PSMA PET positivity. On per-patient analysis, the summary sensitivity and specificity were both 86%. On per-lesion analysis, the summary sensitivity and specificity were 80% and 97%, respectively. CONCLUSIONS In the setting of BCR prostate cancer, pre-PET PSA predicts the risk of positive 68Ga-PSMA PET. Pooled data indicate favourable sensitivity and specificity profiles compared to choline-based PET imaging techniques. PATIENT SUMMARY Positron emission tomography using 68Ga-labelled prostate-specific membrane antigen is an emerging radiological technique developed to improve the characterisation of metastatic prostate cancer. We summarised the data available to date and found that this new test provides excellent rates of detection of cancer spread in late-stage prostate cancer.

Prostate cancer biomarkers: Are we hitting the mark?

Purpose Localised prostate cancer diagnosis and management is increasingly complex due to its heterogeneous progression and prognostic subgroups. Pitfalls in current screening and diagnosis have prompted the search for accurate and invasive molecular and genetic biomarkers for prostate cancer. Such tools may be able to distinguish clinically significant cancers from less aggressive variants to assist with prostate cancer risk stratification and guide decisions and healthcare algorithms. We aimed to provide a comprehensive review of the current prostate cancer biomarkers available and in development. Methods MEDLINE and EMBASE databases searches were conducted to identify articles pertaining to the use of novel biomarkers for prostate cancer. Results A growing number of novel biomarkers are currently under investigation. Such markers include urinary biomarkers, serology-based markers or pathological tissue assessments of molecular and genetic markers. While limited clinical data is present for analysis, early results appear promising. Specifically, a combination of serum and urinary biomarkers (Serum PSA + Urinary PCA3 + Urinary TMPRSS2-ERG fusion) appears to provide superior sensitivity and specificity profiles compared to traditional diagnostic approaches (AUC 0.88). Conclusion The accurate diagnosis and risk stratification of prostate cancer is critical to ensure appropriate intervention. The development of non-invasive biomarkers can add to the information provided by current screening practices and allows for individualised risk stratification of patients. The use of these biomarkers appears to increase the sensitivity and specificity of diagnosis of prostate cancer. Further studies are necessary to define the appropriate use and time points of each biomarker and their effect on the management algorithm of prostate cancer.

Minimally invasive surgical therapies for benign prostatic hypertrophy: The rise in minimally invasive surgical therapies

The prevalence of benign prostatic hypertrophy (BPH) causing bothersome lower urinary tract symptoms increases with our ageing population. Treatment of BPH traditionally begins with medical therapy and surgical intervention is then considered for those whose symptoms progress despite treatment. Minimally invasive surgical therapies have been developed as an intermediary in the treatment of BPH with the aim of decreasing the invasiveness of interventions. These therapies also aim to reduce morbidity and dysfunction related to invasive surgical procedures. Multiple treatment options exist in this group including mechanical and thermo-ablative strategies. Emerging therapies utilizing differing technologies range from the established to the experimental. We review the current literature related to these minimally invasive therapies and the evidence of their effectiveness in treating BPH. The role of minimally invasive surgical therapies in the treatment of BPH is still yet to be strongly defined. Given the experimental nature of many of the modalities, further study is required prior to their recommendation as alternatives to invasive surgical therapy. More mature evidence is required for the analysis of durability of effect of these therapies to make robust conclusions of their effectiveness.

Collaboration Through Communication: The Young Urology Researchers Organisation (YURO).

Young Urology Researchers Organisation (YURO) Todd G. Manning*, Daniel Christidis*, Paul Zotov and Nathan Lawrentschuk* *Department of Surgery, Austin Health, University of Melbourne, Young Urology Researchers Organisation (YURO), Department of Surgery, Alfred Health, Department of Surgical Oncology, Peter MacCallum Cancer Centre, and Olivia Newton John Cancer Research Institute, Melbourne, Vic., Australia

Three dimensional models in uro-oncology: a future built with additive fabrication

PurposeThree-dimensional (3D) printing was invented in 1983 but has only just begun to influence medicine and surgery. Conversion of digital images into physical models demonstrates promise to revolutionize multiple domains of surgery. In the field of uro-oncology, researchers and clinicians have recognized the potential of this technology and are working towards making it an integral part of urological practice. We review current literature regarding 3D printing and other 3D technology in the field of urology.MethodA comprehensive assessment of contemporary literature was performed according to a modified PRISMA analysis for the purposes of this narrative review article. Medical databases that were searched included: Web of Science, EMBASE and Cochrane databases. Articles assessed were limited only to English-language peer-reviewed articles published between 1980 and 2017. The search terms used were “3D”, “3-dimensional”, “printing”, “printing technology”, “urology”, “surgery”. Acceptable articles were reviewed and incorporated for their merit and relevance with preference given for articles with high impact, original research and recent advances.ResultsThirty-five publications were included in final analysis and discussion.ConclusionsThe area of 3D printing in Urology shows promising results, but further research is required and cost reduction must occur before clinicians fully embrace its use. As costs continue to decline and diversity of materials continues to expand, research and clinical utilization will increase. Recent advances have demonstrated the potential of this technology in the realms of education and surgical optimization. The generation of personalized organs using 3D printing scaffolding remains the ‘holy grail’ of this technology.

Prostatic artery embolization for benign prostatic obstruction: assessment of safety and efficacy.

PurposeProstatic artery embolization (PAE) has seen a recent increase in interest as a treatment for men with benign prostatic obstruction (BPO). The appeal of this intervention lies in reported reduction in morbidity and its minimally invasive nature. The purpose of this review is to assess the safety and efficacy of PAE as a new treatment in BPO and explore risks surrounding its performance.MethodsA review of the literature was performed. Medical databases searched included PubMed, EMBASE, and Cochrane databases, limited to English, peer-reviewed articles. Search terms included prostatic artery embolization, lower urinary tracts symptoms, minimally invasive therapies, interventional radiology prostate, and benign prostatic hyperplasia. Articles were screened by two independent reviewers for content on development, methods, outcomes, and complications of PAE.ResultsSuitability of patients to undergo PAE depends on review of patient history, pre-procedure visualisation of appropriate vascular anatomy and clinical parameters. Despite this selection of candidates favourable for procedural success, PAE is not without risk of complications, some of which can significantly affect patient quality of life.ConclusionsAlthough initial findings show promise regarding safety and efficacy of PAE in improving symptom and quality-of-life scores, further investigation is required to establish durability of effect and the appropriate use of this experimental modality. There is currently limited robust evidence for the beneficial outcomes of PAE. Long-term follow-up studies will add to the evidence base to help further assess the feasibility of this procedure as an alternative to TURP.

Interpreting Prostate Multiparametric Magnetic Resonance Imaging: Urologists' Guide Including Prostate Imaging Reporting and Data System

Abstract Objective To review and explain the development of multiparametric MRI and its use in prostate cancer diagnosis while educating on the implication of certain radiological findings. Methods The physics of MRI is reviewed prior to the explanation of different phase technologies in “multiparametric” scanning. Sample images of the prostate are used to display phenomena described Results modalities of multi-parametric MRI of the prostate were reviewed and the interpretation of certain findings displayed on sample images to educate clinicians about their presence and significance. Conclusions Diagnosis, biopsy targeting, surveillance, operative planning and staging has led to endorsement of mpMRI and it is imperative that treating Urologists have an understanding of mpMRI to appreciate the power and limitations of its findings.

Magnetic resonance imaging cognitive fusion biopsy - is near enough good enough?

biopsy – is near enough good enough? Niranjan J. Sathianathen* , Daniel Christidis , Badrinath R. Konety* and Nathan L. Lawrentschuk *Department of Urology, University of Minnesota, Minneapolis, MN, USA, University of Melbourne, Department of Surgery, Urology Unit and Olivia Newton-John Cancer Research Institute Austin Health, Melbourne, Vic., Australia, Young Urology Researchers Organisation (YURO), Melbourne, Vic., Australia, and Department of Surgical Oncology, Peter MacCallum Cancer Centre, Melbourne, Vic., Australia

“Plug and Play”: a novel technique utilising existing technology to get the most out of the robot

We describe a simple technique in which current and freely available technology can be utilised by surgeons while operating the Da Vinci Si/Xi Surgical Robotic systems. This technique allows for a parallel intraoperative display within the surgical console of any desired subject material from a standard computer, utilising commercially available cabling. The ability to view 3D reconstructed images, patient radiology and patient results within the console whilst operating, has the potential to increase operative efficiency, reduce error and aid in adequate resection of tissues. The ease with which our technique is achieved, the benefits of its use and the low cost associated with its implementation support our suggestion that all robotic surgeons incorporate this into their regular operative setup.

Transperineal prostate biopsy – tips for analgesia

The modern transperineal prostate biopsy (TPB) technique was first described in 1983(1). Since its introduction, TPB has become favorable over transrectal ultrasound prostate biopsy (TRUS-PB) approach due to higher cancer detection rates particularly in the anterior and transition zones, lower rates of sepsis, and decreased risk of rectal bleeding(2). Using a standardized template for prostate biopsy – sampling of the prostate is improved with TP prostate biopsy when compared to transrectal-guided biopsy(2). This article is protected by copyright. All rights reserved.