Surgery (Austin & Northern Health) - Research Publications

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    Active surveillance versus enzalutamide for low-risk prostate cancer - was it really a trial we needed?
    Williams, ISC ; Perera, S ; Murphy, DG ; Corcoran, NM ; Bolton, DM ; Lawrentschuk, N (WILEY, 2022-11)
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    Distant Nodes Seen on PSMA PET-CT Staging Predicts Post-Treatment Progression in Men with Newly Diagnosed Prostate Cancer-A Prospective Cohort Study
    Ong, S ; Pascoe, C ; Kelly, BD ; Ballok, Z ; Webb, D ; Bolton, D ; Murphy, D ; Sengupta, S ; Bowden, P ; Lawrentschuk, N (MDPI, 2022-12)
    PSMA PET-CT scans are now recommended in international urological guidelines for primary staging and re-staging of prostate cancer. However, there is little published literature on the clinical outcomes for patients after treatment decisions made using PSMA PET-CT results. This is a multisite, prospective cohort study investigating the clinical outcomes of men who received treatment plans based on PSMA PET-CT results for primary staging. Men with biopsy proven prostate cancer received a PSMA PET-CT scan for primary staging. Treatment plans were recommended by multidisciplinary teams (MDT). After treatment, these men were followed with 6 monthly PSA tests and imaging or biopsies if recommended by MDT. The primary outcome was treatment progression defined as the addition or change of any treatment modalities such as androgen deprivation therapy, radiation therapy or chemotherapy. In total, 80% of men did not have any treatment progression after enactment of treatment based on PSMA PET-CT primary staging results at 29 months of follow up. Men who had distant nodes seen on PSMA PET-CT had a 5 times increased risk of treatment progression. Larger studies with longer follow up are needed to validate our results and optimise the way clinicians use PSMA PET-CT results to guide management.
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    PEDAL protocol: a prospective single-arm paired comparison of multiparametric MRI and 18F-DCPFyl PSMA PET/CT to diagnose prostate cancer
    Tran, V ; Hong, A ; Sutherland, T ; Taubman, K ; Lee, S-F ; Lenaghan, D ; Sethi, K ; Corcoran, NM ; Lawrentschuk, N ; Woo, H ; Tarlinton, L ; Bolton, D ; Spelman, T ; Thomas, L ; Booth, R ; Hegarty, J ; Perry, E ; Wong, L-M (BMJ PUBLISHING GROUP, 2022-09)
    INTRODUCTION: Prostate-specific membrane antigen positron emission tomography (PSMA-PET) has emerged as valuable imaging to assessing metastatic disease in prostate malignancy. However, there has been limited studies exploring the utility PSMA-PET as primary imaging assessing for index lesions prior to biopsy. The primary objective of this study is to compare the diagnostic accuracy of 18-fluorine PSMA (18F DCFPyL PSMA) PET scans to multiparametric MRI (mpMRI) to detect primary prostate cancer at prostate biopsy. METHODS AND ANALYSIS: The PEDAL trial is a multicentre, prospective, single-arm, paired comparison, non-randomised phase III trial in subjects considered for diagnostic prostate biopsy. Subjects who are eligible for a diagnostic mpMRI prostate will undergo additional same-day 18 F DCFPyl PSMA PET/CT of the chest, abdomen and pelvis. Software coregistration of the mpMRI and PSMA-PET/CT images will be performed. The reporting of the mpMRI prostate, PSMA-PET/CT and PSMA PET/MRI coregistration will be performed blinded. The diagnostic accuracy of PSMA PET/CT alone, and in combination with mpMRI, to detect prostate cancer will be assessed. Histopathology at prostate biopsy will be used as the reference standard. Sample size calculations estimate that 240 subjects will need to be recruited to demonstrate 20% superiority of PSMA-PET/CT. The sensitivity, specificity, positive predictive value and negative predictive value of the combination of mpMRI prostate and PSMA PET/CT compared with targeted and systematic prostate biopsy will be evaluated. It is hypothesised that PSMA PET/CT combined with mpMRI prostate will have improved diagnostic accuracy compared with mpMRI prostate alone for detection of prostate cancer in biopsy-naïve men, resulting in a significant impact on patient management. ETHICS AND DISSEMINATION: This study was approved by the independent Human Research Ethics Committee. Results will be published in peer-reviewed medical journals with eligible investigators will significantly contribute. TRIAL REGISTRATION NUMBER: ACTRN12620000261910.
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    Tumor immune microenvironment of primary prostate cancer with and without germline mutations in homologous recombination repair genes
    Trigos, AS ; Pasam, A ; Banks, P ; Wallace, R ; Guo, C ; Keam, S ; Thorne, H ; Mitchell, C ; Lade, S ; Clouston, D ; Hakansson, A ; Liu, Y ; Blyth, B ; Murphy, D ; Lawrentschuk, N ; Bolton, D ; Moon, D ; Darcy, P ; Haupt, Y ; Williams, SG ; Castro, E ; Olmos, D ; Goode, D ; Neeson, P ; Sandhu, S (BMJ PUBLISHING GROUP, 2022-06)
    BACKGROUND: Aberrations in homologous recombination repair (HRR) genes are emerging as important biomarkers for personalized treatment in prostate cancer (PCa). HRR deficiency (HRD) could affect the tumor immune microenvironment (TIME), potentially contributing to differential responses to poly ADP-ribose polymerase (PARP) inhibitors and immune checkpoint inhibitors. Spatial distribution of immune cells in a range of cancers identifies novel disease subtypes and is related to prognosis. In this study we aimed to determine the differences in the TIME of PCa with and without germline (g) HRR mutations. METHODS: We performed gene expression analysis, multiplex immunohistochemistry of T and B cells and quantitative spatial analysis of PCa samples from 36 patients with gHRD and 26 patients with sporadic PCa. Samples were archival tumor tissue from radical prostatectomies with the exception of one biopsy. Results were validated in several independent cohorts. RESULTS: Although the composition of the T cell and B cells was similar in the tumor areas of gHRD-mutated and sporadic tumors, the spatial profiles differed between these cohorts. We describe two T-cell spatial profiles across primary PCa, a clustered immune spatial (CIS) profile characterized by dense clusters of CD4+ T cells closely interacting with PD-L1+ cells, and a free immune spatial (FIS) profile of CD8+ cells in close proximity to tumor cells. gHRD tumors had a more T-cell inflamed microenvironment than sporadic tumors. The CIS profile was mainly observed in sporadic tumors, whereas a FIS profile was enriched in gHRD tumors. A FIS profile was associated with lower Gleason scores, smaller tumors and longer time to biochemical recurrence and metastasis. CONCLUSIONS: gHRD-mutated tumors have a distinct immune microenvironment compared with sporadic tumors. Spatial profiling of T-cells provides additional information beyond T-cell density and is associated with time to biochemical recurrence, time to metastasis, tumor size and Gleason scores.
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    PSMA PET-CT Imaging Predicts Treatment Progression in Men with Biochemically Recurrent Prostate Cancer-A Prospective Study of Men with 3 Year Follow Up
    Ong, S ; Pascoe, C ; Kelly, BD ; Ballok, Z ; Webb, D ; Bolton, D ; Murphy, D ; Sengupta, S ; Bowden, P ; Lawrentschuk, N (MDPI, 2022-06)
    Prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is a novel imaging modality used to stage recurrent prostate cancer. It has the potential to improve prognostication and ultimately guide the timing of treatment for men with recurrent prostate cancer. This study aims to assess the clinical impact of PSMA PET-CT by analyzing its predictive value of treatment progression after 3 years of follow-up. In this prospective cohort study of 100 men, patients received a PSMA PET-CT for restaging of their disease which was used by a multi-disciplinary team to make a treatment decision. The primary endpoint was treatment progression. This was defined as the addition or change of any treatment modalities such as androgen deprivation therapy (ADT), radiation therapy or chemotherapy. The median follow-up time was 36 months (IQR 24-40 months). No treatment progression was found in 72 (75%) men and therefore 24 (25%) patients were found to have treatment progression. In men with a negative PSMA PET-CT result, 5/33 (15.1%) had treatment progression and 28/33 (84.8%) had no treatment progression. In conclusion, clinical decisions made with PSMA PET-CT results led to 75% of men having no treatment progression at 3 years of follow-up. In men with negative PSMA PET-CT results, this increased to 85% of men.
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    Cribriform pattern disease over-represented in pelvic lymph node metastases identified on 68GA PSMA-PET/CT
    Bolton, D ; Hong, A ; Papa, N ; Perera, M ; Kelly, B ; Duncan, C ; Clouston, D ; Lawrentschuk, N (WILEY, 2022-09)
    OBJECTIVES: To determine whether any specific histologic subtype of prostate cancer was preferentially represented in pelvic lymph node metastases identified on 68GA-PSMA-PET/CT. SUBJECTS AND METHODS: A consecutive series of 66 men with biochemical recurrent prostate cancer was evaluated with 68GA-PSMA-PET/CT. Where disease was confined to pelvic lymph nodes, patients were offered salvage extended pelvic lymph node dissection. Twenty patients ultimately proceeded to extended bilateral template pelvic lymph node dissection. Lymph node positivity and the histologic subtype of apparent cancer were assessed, as was PSA response to this intervention. RESULTS: Mean PSA at time of PSMA scanning for patients undergoing lymphadenectomy was 2.49 (n = 20, range 0.21-12.0). In 16 of 20 patients, there was evidence of metastatic cribriform pattern prostate cancer in excised nodes (100% cribriform pattern in 11/16). Only four of 20 patients had no evidence of this histologic subtype of disease. PSA response was not related to the presence or proportional amount of cribriform pattern disease identified. CONCLUSIONS: Cribriform pattern adenocarcinoma appears to be the histologic subtype preferentially identified in pelvic lymph nodes on 68GA-PSMA-PET/CT. The use of PSMA-PET may be particularly valuable in staging of primary or biochemically recurrent prostate cancer in patients with cribriform pattern disease detected on initial biopsy or radical prostatectomy. Further research is required to further confirm the observed association.
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    3D printed patient-specific prostate cancer models to guide nerve-sparing robot-assisted radical prostatectomy: a systematic review
    Coles-Black, J ; Ong, S ; Teh, J ; Kearns, P ; Ischia, J ; Bolton, D ; Lawrentschuk, N (SPRINGERNATURE, 2023-02)
    Precise knowledge of each patient's index cancer and surrounding anatomy is required for nerve-sparing robot-assisted radical prostatectomy (NS-RARP). Complementary to this, 3D printing has proven its utility in improving the visualisation of complex anatomy. This is the first systematic review to critically assess the potential of 3D printed patient-specific prostate cancer models in improving visualisation and the practice of NS-RARP. A literature search of PubMed and OVID Medline databases was performed using the terms "3D Printing", "Robot Assisted Radical Prostatectomy" and related index terms as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Eight articles were included; six were identified via database searches, to which a further two articles were located via a snowballing approach. Eight papers were identified for review. There were five prospective single centre studies, one case series, one technical report and one letter to the editor. Of these articles, five publications (62.5%) reported on the utility of 3D printed models for NS-RARP planning. Two publications (25%) utilised 3D printed prostate models for simulation and training, and two publications (25%) used the models for patient engagement. Despite the nascency of the field, 3D printed models are emerging in the uro-oncological literature as a useful tool in visualising complex anatomy. This has proven useful in NS-RARP for preoperative planning, simulation and patient engagement. However, best practice guidelines, the future regulatory landscape, and health economic considerations need to be addressed before this synergy of new technologies is ready for the mainstream.
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    Review of the use of prophylactic drain tubes post-robotic radical prostatectomy: Dogma or decent practice?
    Nzenza, TC ; Ngweso, S ; Eapen, R ; Rajarubendra, N ; Bolton, D ; Murphy, D ; Lawrentschuk, N (WILEY, 2020-09)
    OBJECTIVE: To assess the necessity of routine prophylactic drain tube use following robot-assisted radical prostatectomy (RARP). METHOD: We performed a literature review using the Medline, Scopus, and Web of Science databases with no restriction of language from January 1900 to January 2020. The following terms we used in the literature search: prostatectomy, radical prostatectomy, robot assisted, drainage, and drain tube. RESULTS: We identified six studies that examined the use of routine prophylactic drain tubes following RARP. One of these studies was a randomized study that included 189 patients, with 97 in the pelvic drain (PD) arm and 92 in the no pelvic drain (ND) arm. This non-inferiority showed an early (90-day) complication rate of 17.4% in the ND arm versus 26.8% in the PD arm (P < .001). Another non-inferiority randomized control trial (RCT) showed a complication rate of 28.9% in the PD group versus 20.4% in the ND group (P = .254). Similarly, the other studies found no benefit of routine use of prophylactic drain tube after RARP. CONCLUSION: Drain tubes play a role during robotic-assisted radical prostatectomy, however, following a review of the current available literature, they can be safely omitted and we suggest that clinicians may be selective in their use.
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    Prostate-specific membrane antigen for the surgical oncologist: interpreting expression beyond the prostate
    Farag, M ; Bolton, D ; Lawrentschuk, N (WILEY, 2020-05)
    The use of prostate-specific membrane antigen (PSMA) radiotracer in positron emission tomography (PET) has been successfully incorporated into the clinical management of prostate cancer. However, PSMA tracer uptake is not limited to prostate cancer tissue. We reviewed studies exploring PSMA expression beyond the prostate gland using techniques of 68 Ga-PSMA PET imaging and immunohistochemistry. PSMA expression has been associated with a variety of solid tumours, and the vasculature associated with neoplastic disease, suggesting that this trans-membrane glycoprotein may be involved in the neovascularisation process in malignancy. These studies demonstrate the need for more research into the potential utility for 68 Ga-PSMA PET imaging in patients with non-prostatic cancers.