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Malignant pleural mesothelioma (MPM) is an aggressive primary malignancy of the pleura that presents unique radiologic challenges with regards to accurate and reproducible assessment of disease extent at staging and follow-up imaging. By optimizing and harmonizing technical approaches to imaging MPM, the best quality imaging can be achieved for individual patient care, clinical trials and imaging research. This consensus statement represents agreement on harmonized, standard practices for routine multi-modality imaging of MPM, including radiography, computed tomography (CT)

Positron emission tomography (PET) imaging using the amino acid tracer O-[2-(18F)fluoroethyl]-L-tyrosine (FET) has gained increased popularity within the past decade in the management of glioblastoma (GBM). Radiomics features extracted from FET PET images may be sensitive to variations when imaging at multiple time points. It is therefore necessary to assess feature robustness to test-retest imaging. Eight patients with histologically confirmed GBM that had undergone post-surgical test-retest FET PET imaging were recruited. In total, 1578 radiomic features were extracted from biological tumour volumes (BTVs) delineated using a semi-automatic contouring method. Feature repeatability was assessed using the intraclass correlation coefficient (ICC). The effect of both bin width and filter choice on feature repeatability was also investigated. 59/106 (55.7%) features from the original image and 843/1472 (57.3%) features from filtered images had an ICC ≥ 0.85. Shape and first order features were most stable. Choice of bin width showed minimal impact on features defined as stable. The Laplacian of Gaussian (LoG, σ = 5 mm) and Wavelet filters (HLL and LHL) significantly improved feature repeatability (p ≪ 0.0001, p = 0.003, p = 0.002, respectively). Correlation of textural features with tumour volume was reported for transparency. FET PET radiomic features extracted from post-surgical images of GBM patients that are robust to test-retest imaging were identified. An investigation with a larger dataset is warranted to validate the findings in this study.

Previously, results from the TheraP trial showed that treatment with lutetium-177 [TheraP was a multicentre, open-label, randomised phase 2 trial that recruited men with metastatic castration-resistant prostate cancer after treatment with docetaxel who were suitable for cabazitaxel from 11 hospitals in Australia. Participants were required to be 18 years old or older; have adequate haematological, renal, and liver function; and an Eastern Cooperative Oncology Group performance status of 0-2. Participants were randomly assigned (1:1) using a centralised system using minimisation with a random component and that stratified patients by disease burden, previous treatment with enzalutamide or abiraterone, and study site. Patients were either given cabazitaxel (20 mg/m200 patients were randomly assigned between Feb 6, 2018, and Sept 3, 2019. 101 men were assigned to the cabazitaxel group and 99 were assigned to the [In men with metastatic castration-resistant prostate cancer, PSMA-PET SUVmean was predictive of higher likelihood of favourable response to [Prostate Cancer Foundation of Australia, Endocyte (a Novartis Company), Australian Nuclear Science and Technology Organisation, Movember Foundation, It's a Bloke Thing, CAN4CANCER, The Distinguished Gentleman's Ride.

Purpose This study aimed to develop and assess an automated segmentation framework based on deep learning for metastatic prostate cancer (mPCa) lesions in whole-body [68Ga]Ga-PSMA-11 PET/CT images for the purpose of extracting patient-level prognostic biomarkers. Methods Three hundred thirty-seven [68Ga]Ga-PSMA-11 PET/CT images were retrieved from a cohort of biochemically recurrent PCa patients. A fully 3D convolutional neural network (CNN) is proposed which is based on the self-configuring nnU-Net framework, and was trained on a subset of these scans, with an independent test set reserved for model evaluation. Voxel-level segmentation results were assessed using the dice similarity coefficient (DSC), positive predictive value (PPV), and sensitivity. Sensitivity and PPV were calculated to assess lesion level detection; patient-level classification results were assessed by the accuracy, PPV, and sensitivity. Whole-body biomarkers total lesional volume (TLVauto) and total lesional uptake (TLUauto) were calculated from the automated segmentations, and Kaplan–Meier analysis was used to assess biomarker relationship with patient overall survival. Results At the patient level, the accuracy, sensitivity, and PPV were all > 90%, with the best metric being the PPV (97.2%). PPV and sensitivity at the lesion level were 88.2% and 73.0%, respectively. DSC and PPV measured at the voxel level performed within measured inter-observer variability (DSC, median = 50.7% vs. second observer = 32%, p = 0.012; PPV, median = 64.9% vs. second observer = 25.7%, p auto and TLUauto showed they were significantly associated with patient overall survival (both p Conclusion The fully automated assessment of whole-body [68Ga]Ga-PSMA-11 PET/CT images using deep learning shows significant promise, yielding accurate scan classification, voxel-level segmentations within inter-observer variability, and potentially clinically useful prognostic biomarkers associated with patient overall survival. Trial registration This study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12615000608561) on 11 June 2015.

Objective To assess the activity and safety of sequential lutetium-177 (Lu-177)-PSMA-617 and docetaxel vs docetaxel on a background of androgen deprivation therapy (ADT) in men with de novo metastatic hormone-naive prostate cancer (mHNPC).Patients and Methods UpFrontPSMA (NCT04343885) is an open-label, randomized, multicentre, phase 2 trial, recruiting 140 patients at 12 Australian centres. Key eligibility criteria include: prostate cancer with a histological diagnosis within 12 weeks of screening commencement; prostate-specific antigen (PSA) >10 ng/mL at diagnosis; 15; and absence of extensive discordant fluorodeoxyglcuose (FDG)-positive, PSMA-negative disease. Ga-68-PSMA-11 and F-18-FDG positron-emission tomography (PET)/CT undergo central review to determine eligibility. Patients are randomized 1:1 to experimental treatment, Arm A (Lu-177-PSMA-617 7.5GBq q6w x 2 cycles followed by docetaxel 75 mg/m(2) q3w x 6 cycles), or standard-of-care treatment, Arm B (docetaxel 75 mg/m(2) q3w x 6 cycles). All patients receive continuous ADT. Patients are stratified based on disease volume on conventional imaging and duration of ADT at time of registration. The primary endpoint is the proportion of patients with undetectable PSA (

There is currently no treatment for attenuating progression of arterial calcification. 18F-sodium fluoride positron emission tomography (18F-NaF PET) locates regions of calcification activity. We tested whether vitamin-K1 or colchicine affected arterial calcification activity. 154 patients with diabetes mellitus and coronary calcification, as detected using computed tomography (CT), were randomized to one of four treatment groups (placebo/placebo, vitamin-K1 [10 mg/day]/placebo, colchicine [0.5 mg/day]/placebo, vitamin-K1 [10 mg/day]/ colchicine [0.5 mg/day]) in a double-blind, placebo-controlled 2x2 factorial trial of three months duration. Change in coronary calcification activity was estimated as a change in coronary maximum tissue-to-background ratio (TBRmax) on 18F-NaF PET. 149 subjects completed follow-up (vitamin-K1: placebo = 73:76 and colchicine: placebo = 73:76). Neither vitamin-K1 nor colchicine had a statistically significant effect on the coronary TBRmax compared with placebo (mean difference for treatment groups 0·00 ± 0·16 and 0·01 ± 0·17, respectively, p > 0.05). There were no serious adverse effects reported with colchicine or vitamin-K1. In patients with type 2 diabetes, neither vitamin-K1 nor colchicine significantly decreases coronary calcification activity, as estimated by 18F-NaF PET, over a period of 3 months. Clinical trial registration: ACTRN12616000024448.

Background Before integrating prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) into routine care, it is important to assess if the benefits justify the differences in resource use. Objective To determine the cost-effectiveness of PSMA-PET/CT when compared with conventional imaging. Design, setting, and participants A cost-effectiveness analysis was developed using data from the proPSMA study. proPSMA included patients with high-risk prostate cancer assigned to conventional imaging or 68Ga-PSMA-11 PET/CT with planned health economics data collected. The cost-effectiveness analysis was conducted from an Australian societal perspective. Intervention 68Ga-PSMA-11 PET/CT compared with conventional imaging (CT and bone scan). Outcome measurements and statistical analysis The primary outcome from proPSMA was diagnostic accuracy (nodal and distant metastases). This informed a decision tree analysis of the cost per accurate diagnosis. Results and limitations The estimated cost per scan for PSMA PET/CT was AUD$1203, which was less than the conventional imaging cost at AUD$1412. PSMA PET/CT was thus dominant, having both better accuracy and a lower cost. This resulted in a cost of AUD$959 saved per additional accurate detection of nodal disease, and AUD$1412 saved for additional accurate detection of distant metastases. The results were most sensitive to variations in the number of men scanned for each 68Ga-PSMA-11 production run. Subsequent research is required to assess the long-term costs and benefits of PSMA PET/CT-directed care. Conclusions PSMA PET/CT has lower direct comparative costs and greater accuracy compared to conventional imaging for initial staging of men with high-risk prostate cancer. This provides a compelling case for adopting PSMA PET/CT into clinical practice. Patient summary The proPSMA study demonstrated that prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) better detects disease that has spread beyond the prostate compared with conventional imaging. Our analysis shows that PSMA PET/CT is also less costly than conventional imaging for the detection of disease spread. This research was presented at the European Association of Nuclear Medicine Scientific Meeting in October 2020.

Summary Background Lutetium-177 [177Lu]Lu-PSMA-617 is a radiolabelled small molecule that delivers β radiation to cells expressing prostate-specific membrane antigen (PSMA), with activity and safety in patients with metastatic castration-resistant prostate cancer. We aimed to compare [177Lu]Lu-PSMA-617 with cabazitaxel in patients with metastatic castration-resistant prostate cancer. Methods We did this multicentre, unblinded, randomised phase 2 trial at 11 centres in Australia. We recruited men with metastatic castration-resistant prostate cancer for whom cabazitaxel was considered the next appropriate standard treatment. Participants were required to have adequate renal, haematological, and liver function, and an Eastern Cooperative Oncology Group performance status of 0–2. Previous treatment with androgen receptor-directed therapy was allowed. Men underwent gallium-68 [68Ga]Ga-PSMA-11 and 2-flourine-18[18F]fluoro-2-deoxy-D-glucose (FDG) PET-CT scans. PET eligibility criteria for the trial were PSMA-positive disease, and no sites of metastatic disease with discordant FDG-positive and PSMA-negative findings. Men were randomly assigned (1:1) to [177Lu]Lu-PSMA-617 (6·0–8·5 GBq intravenously every 6 weeks for up to six cycles) or cabazitaxel (20 mg/m2 intravenously every 3 weeks for up to ten cycles). The primary endpoint was prostate-specific antigen (PSA) response defined by a reduction of at least 50% from baseline. This trial is registered with ClinicalTrials.gov, NCT03392428. Findings Between Feb 6, 2018, and Sept 3, 2019, we screened 291 men, of whom 200 were eligible on PET imaging. Study treatment was received by 98 (99%) of 99 men randomly assigned to [177Lu]Lu-PSMA-617 versus 85 (84%) of 101 randomly assigned to cabazitaxel. PSA responses were more frequent among men in the [177Lu]Lu-PSMA-617 group than in the cabazitaxel group (65 vs 37 PSA responses; 66% vs 37% by intention to treat; difference 29% (95% CI 16–42; p Interpretation [177Lu]Lu-PSMA-617 compared with cabazitaxel in men with metastatic castration-resistant prostate cancer led to a higher PSA response and fewer grade 3 or 4 adverse events. [177Lu]Lu-PSMA-617 is a new effective class of therapy and a potential alternative to cabazitaxel. Funding Prostate Cancer Foundation of Australia, Endocyte (a Novartis company), Australian Nuclear Science and Technology Organization, Movember, The Distinguished Gentleman's Ride, It's a Bloke Thing, and CAN4CANCER.

Background: Conventional imaging using CT and bone scan has insufficient sensitivity when staging men with high-risk localised prostate cancer. We aimed to investigate whether novel imaging using prostate-specific membrane antigen (PSMA) PET-CT might improve accuracy and affect management. Methods: In this multicentre, two-arm, randomised study, we recruited men with biopsy-proven prostate cancer and high-risk features at ten hospitals in Australia. Patients were randomly assigned to conventional imaging with CT and bone scanning or gallium-68 PSMA-11 PET-CT. First-line imaging was done within 21 days following randomisation. Patients crossed over unless three or more distant metastases were identified. The primary outcome was accuracy of first-line imaging for identifying either pelvic nodal or distant-metastatic disease defined by the receiver-operating curve using a predefined reference-standard including histopathology, imaging, and biochemistry at 6-month follow-up. This trial is registered with the Australian New Zealand Clinical Trials Registry, ANZCTR12617000005358. Findings: From March 22, 2017 to Nov 02, 2018, 339 men were assessed for eligibility and 302 men were randomly assigned. 152 (50%) men were randomly assigned to conventional imaging and 150 (50%) to PSMA PET-CT. Of 295 (98%) men with follow-up, 87 (30%) had pelvic nodal or distant metastatic disease. PSMA PET-CT had a 27% (95% CI 23–31) greater accuracy than that of conventional imaging (92% [88–95] vs 65% [60–69]; p

Imaging of mesothelioma plays a role in all aspects of patient management, including disease detection, staging, evaluation of treatment options, response assessment, pre-surgical evaluation, and surveillance. Imaging in this disease impacts a wide range of disciplines throughout the healthcare enterprise. Researchers and clinician-scientists are developing state-of-the-art techniques to extract more of the information contained within these medical images and to utilize it for more sophisticated tasks; moreover, image-acquisition technology is advancing the inherent capabilities of these images. This paper summarizes the imaging-based topics presented orally at the 2021 International Conference of the International Mesothelioma Interest Group (iMig), which was held virtually from May 7-9, 2021. These topics include an update on the mesothelioma staging system, novel molecular targets to guide therapy in mesothelioma, special considerations and potential pitfalls in imaging mesothelioma in the immunotherapy setting, tumor measurement strategies and their correlation with patient survival, tumor volume measurement in MRI and CT, CT-based texture analysis for differentiation of histologic subtype, diffusion-weighted MRI for the assessment of biphasic mesothelioma, and the prognostic significance of skeletal muscle loss with chemotherapy.

IntroductionPreclinical, clinical and epidemiological studies support the hypothesis that aberrant systemic metabolism of amyloid-beta (Aβ) in the peripheral circulation is causally related to the development of Alzheimer’s disease (AD). Specifically, recent studies suggest that increased plasma concentrations of lipoprotein-Aβ compromises the brain microvasculature, resulting in extravasation and retention of the lipoprotein-Aβ moiety. The latter results in an inflammatory response and neurodegeneration ensues.Probucol, a historic cholesterol-lowering drug, has been shown in murine models to suppress lipoprotein-Aβ secretion, concomitant with maintaining blood-brain-barrier function and suppressing neurovascular inflammation. Probucol has also been shown to protect cognitive function in dietary-induced amyloidogenic mice.This protocol details the Probucol in Alzheimer’s Study (PIA-study), a double-blind, randomised, placebo-controlled drug intervention trial investigating if Probucol attenuates cognitive decline in patients with mild-to-moderate AD.ObjectivesThe primary objective of the 104-week study is to assess whether Probucol supports cognitive function and delays brain atrophy in AD patients. A secondary objective is to determine whether Probucol treatment will reduce cerebral amyloid burden.Methods & AnalysisThe study is a phase II single-site, randomised, placebo-controlled, double-blind clinical trial assessing the efficacy of Probucol in AD. A total of 300 participants with mild-to-moderate AD will be recruited and randomised 1:1 (active: placebo). Cognitive function, regional volumetric changes in brain and cerebral amyloid load will be evaluated via the cognitive subscale test, AD assessment scales (ADAS-Cog), magnetic resonance imaging (MRI) and positron emission tomography (PET) scans, respectively, after a 104-week intervention.Ethics & DisseminationThe study has been approved by the Bellberry Limited Human Research Ethics Committee (Approval number: HREC2019-11-1063; Version 4, 6thOctober 2021). The investigator group will disseminate study findings through peer-reviewed publications, key conferences and local stakeholder events.Trial registrationThis trial has been registered with the Australian New Zealand Clinical Trial Registry (ACTRN12621000726853).ARTICLE SUMMARYStrengths and limitations of this studyThis is the first-in-human (FIH) randomised double-blind placebo-controlled study to assess the efficacy of Probucol in delaying cognitive decline in individuals with mild cognitive impairment (MCI) and mild-to-moderate dementia due to Alzheimer’s disease (AD).The 24-month intervention study will be the first to investigate whether treatment with Probucol will stabilise structural/functional changes in brain and if cerebral amyloid load will decrease in individuals with AD, following treatment with Probucol.Probucol is clinically used to treat cardiovascular disease with well-characterised efficacy and safety profiles, thus reducing risk of the study, and if applicable, accelerate clinical translation of the study findings.

Several lines of study suggest that peripheral metabolism of amyloid beta (Aß) is associated with risk for Alzheimer disease (AD). In blood, greater than 90% of Aß is complexed as an apolipoprotein, raising the possibility of a lipoprotein-mediated axis for AD risk. In this study, we report that genetic modification of C57BL/6J mice engineered to synthesise human Aß only in liver (hepatocyte-specific human amyloid (HSHA) strain) has marked neurodegeneration concomitant with capillary dysfunction, parenchymal extravasation of lipoprotein-Aß, and neurovascular inflammation. Moreover, the HSHA mice showed impaired performance in the passive avoidance test, suggesting impairment in hippocampal-dependent learning. Transmission electron microscopy shows marked neurovascular disruption in HSHA mice. This study provides causal evidence of a lipoprotein-Aß /capillary axis for onset and progression of a neurodegenerative process., It has been suggested that peripheral metabolism of amyloid-beta is associated with risk for Alzheimer’s disease. This study reveals that the expression of human amyloid exclusively in the liver induces Alzheimer’s disease-like pathologies in mice, potentially indicating a completely novel pathway of Alzheimer’s disease aetiology and therapies.

Background:68Ga PSMA PET CT (PSMA) is increasingly used in men with biochemical recurrence (BCR) post radical prostatectomy (RP), but its longer term prognostic / predictive potential in these men is unknown. The aim of this study was to evaluate the predictive value of PSMA PET for 3 year freedom from progression (FFP) in men with BCR post RP undergoing salvage radiotherapy (sRT). Methods: This prospective multi-center study enrolled 260 men between 2015 and 2017. Eligible patients were referred for PSMA with rising PSA following RP. Management following PSMA was recorded but not mandated. PSMA protocols were standardised across sites and reported prospectively. Clinical, pathological and surgical information, sRT, timing and duration of androgen deprivation (ADT), 3 year PSA results and clinical events were documented. FFP was defined as a PSA rise ≤ 0.2ng/mL above nadir post sRT, with no additional treatment. Results: The median PSA was 0.26ng/mL (IQR 0.15 - 0.59) and follow-up 38 months (IQR 31-43). PSMA was negative in 34.6% (90/260), confined to prostate fossa 21.5% (56/260), pelvic nodes 26.2% (68/260), and distant disease 17.7% (46/260). 71.5% (186/260) received sRT, 38.2% (71/186) to the fossa only, 49.4% (92/186) fossa + pelvic nodes and 12.4% (23/186) nodes alone/SBRT. PSMA was highly predictive of FFP at 3 years following sRT. Overall, FFP was achieved in 64.5% (120/186) of those who received sRT, 81% (81/100) with negative/fossa confined vs. 45% (39/86) for extra fossa disease (p

Objective To assess the activity and safety of cabazitaxel chemotherapy vs that of treatment with 177 Lu-PSMA-617, a novel radiolabelled small molecule that binds with high affinity to prostate-specific membrane antigen (PSMA), in men with metastatic castration-resistant prostate cancer (mCRPC) who have received prior docetaxel treatment. Patients and methods The TheraP trial (ANZUP 1603) is an open-label, randomized, stratified, two-arm multicentre phase 2 trial comparing the activity and safety of cabazitaxel chemotherapy vs 177 Lu-PSMA-617 therapy in the treatment of men with mCRPC. Key eligibility criteria include prior docetaxel chemotherapy, rising prostate-specific antigen (PSA) level, sufficient PSMA avidity, as defined by centrally reviewed 68 Ga-PSMA-11 and fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) with no discordant FDG-avid PSMA-negative sites of disease. Patients in the control group receive standard treatment with cabazitaxel (20 mg/m2 ) i.v. every 3 weeks with prednisolone 10 mg daily orally, for a maximum of 10 cycles. Patients in the experimental group receive 177 Lu-PSMA-617 (8.5 GBq decreasing by 0.5 GBq per cycle) i.v. every 6 weeks, for up to a maximum of six cycles. In the event of an exceptional response as defined on centrally reviewed post-therapy single-photon emission CT imaging, treatment will be suspended but can recommence on progression. The trial aims to include 200 patients who will be centrally randomized to one of the two treatment groups, in a 1:1 ratio. The primary endpoint is PSA response. Secondary endpoints are overall survival, progression-free survival (PFS), radiographic PFS, PSA PFS, objective tumour response, pain response, pain PFS, health-related quality of life, and frequency and severity of adverse events. The treatment and outcomes of patients excluded on the basis of low PSMA avidity or discordant FDG-avid disease on screening 68 Ga-PSMA-11 and Fluorine-18 (18 F)-FDG-PET/CT scan will also be assessed. Enrolment in the study commenced on 29 January 2018. Results and conclusions 177 Lu-PSMA-617 offers a potential additional life-prolonging treatment option for men with mCRPC. The results of this trial will determine, for the first time in a randomized design, the activity and safety of 177 Lu-PSMA-617, as compared with cabazitaxel chemotherapy in men with progressive mCRPC.

Mesothelioma patients rely on the information their clinical team obtains from medical imaging. Whether x-ray-based computed tomography (CT) or magnetic resonance imaging (MRI) based on local magnetic fields within a patient’s tissues, different modalities generate images with uniquely different appearances and information content due to the physical differences of the image-acquisition process. Researchers are developing sophisticated ways to extract a greater amount of the information contained within these images. This paper summarizes the imaging-based research presented orally at the 2018 International Conference of the International Mesothelioma Interest Group (iMig) in Ottawa, Ontario, Canada, held May 2-5, 2018. Presented topics included advances in the imaging of preclinical mesothelioma models to inform clinical therapeutic strategies, optimization of the time delay between contrast administration and image acquisition for maximized enhancement of mesothelioma tumor on CT, an investigation of image-based criteria for clinical tumor and nodal staging of mesothelioma by contrast-enhanced CT, an investigation of methods for the extraction of mesothelioma tumor volume from MRI and the association of volume with patient survival, the use of deep learning for mesothelioma tumor segmentation in CT, and an evaluation of CT-based radiomics for the prognosis of mesothelioma patient survival.

Objectives To determine the activity and safety of lutetium-177 (177 Lu)-prostate-specific membrane antigen (PSMA)-617 in men with metastatic castration-resistant prostate cancer (mCRPC) commencing enzalutamide, who are at high risk of early progression, and to identify potential prognostic and predictive biomarkers from imaging, blood and tissue. Participants and methods ENZA-p (ANZUP 1901) is an open-label, randomized, two-arm, multicentre, phase 2 trial. Participants are randomly assigned (1:1) to treatment with enzalutamide 160 mg daily alone or enzalutamide plus 177 Lu-PSMA-617 7.5 GBq on Days 15 and 57. Two additional 177 Lu-PSMA-617 doses are allowed, informed by Day-92 Gallium-68 (68 Ga)-PSMA positron emission tomography (PET; up to four doses in total). The primary endpoint is prostate-specific antigen (PSA) progression-free survival (PFS). Other major endpoints include radiological PFS, PSA response rate, overall survival, health-related quality of life, adverse events and cost-effectiveness. Key eligibility criteria include: biochemical and/or clinical progression; 68 Ga-PSMA PET-avid disease; no prior androgen signalling inhibitor, excepting abiraterone; no prior chemotherapy for mCRPC; and ≥2 high-risk features for early enzalutamide failure. Assessments are 4 weekly during study treatment, then 6 weekly until radiographic progression. Response Evaluation Criteria in Solid Tumours (RECIST) are used to assess imaging conducted every 12 weeks, 68 Ga-PSMA PET at baseline, Days 15 and 92, and at progression, and 18 F-fluorine deoxyglucose (18 F-FDG) PET at baseline and progression. Translational samples include blood (and optional biopsies) at baseline, Day 92, and first progression. Correlative studies include identification of prognostic and predictive biomarkers from 68 Ga-PSMA and 18 F-FDG PET/CT, circulating tumour cells and circulating tumour DNA. The trial will enrol 160 participants, providing 80% power with a two-sided type-1 error rate of 5% to detect a hazard ratio of 0.625 assuming a median PSA-PFS of 5 months with enzalutamide alone. Results and conclusion The combination of 177 Lu-PSMA-617 and enzalutamide may be synergistic. ENZA-p will determine the safety and efficacy of the combination in addition to developing predictive and prognostic biomarkers to better guide treatment decisions.

Background Coronary and aortic artery calcifications are generally slow to develop, and their burden predicts cardiovascular disease events. In patients with diabetes mellitus, arterial calcification is accelerated and calcification activity can be detected using 18F-sodium fluoride positron emission tomography (18F-NaF PET). Objectives We aimed to determine whether vitamin K1 supplementation inhibits arterial calcification activity in individuals with diabetes mellitus. Methods This was a post hoc analysis of the ViKCoVaC (effect of Vitamin-K1 and Colchicine on Vascular Calcification activity in subjects with Diabetes Mellitus) double-blind randomized controlled trial conducted in Perth, Western Australia. Individuals with diabetes mellitus and established coronary calcification (coronary calcium score > 10), but without clinical coronary artery disease, underwent baseline 18F-NaF PET imaging, followed by oral vitamin K1 supplementation (10 mg/d) or placebo for 3 mo, after which 18F-NaF PET imaging was repeated. We tested whether individuals randomly assigned to vitamin K1 supplementation had reduced development of new 18F-NaF PET positive lesions within the coronary arteries and aorta. Results In total, 149 individuals completed baseline and follow-up imaging studies. Vitamin K1 supplementation independently decreased the odds of developing new 18F-NaF PET positive lesions in the coronary arteries (OR: 0.35; 95% CI: 0.16, 0.78; P = 0.010), aorta (OR: 0.27; 95% CI: 0.08, 0.94; P = 0.040), and in both aortic and coronary arteries (OR: 0.28; 95% CI: 0.13, 0.63; P = 0.002). Conclusions In individuals with diabetes mellitus, supplementation with 10 mg vitamin K1/d may prevent the development of newly calcifying lesions within the aorta and the coronary arteries as detected using 18F-NaF PET. Further long-term studies are needed to test this hypothesis.This trial was registered at anzctr.org.au as ACTRN12616000024448.

To assess the activity and safety of sequential lutetium-177 (UpFrontPSMA (NCT04343885) is an open-label, randomized, multicentre, phase 2 trial, recruiting 140 patients at 12 Australian centres. Key eligibility criteria include: prostate cancer with a histological diagnosis within 12 weeks of screening commencement; prostate-specific antigen (PSA)10 ng/mL at diagnosis; ≤4 weeks on ADT; evidence of metastatic disease on computed tomography (CT) and/or bone scan; high-volume prostate-specific membrane antigen (PSMA)-avid disease with a maximum standardized uptake value15; and absence of extensive discordant fluorodeoxyglcuose (FDG)-positive, PSMA-negative disease.The results of this trial will generate data on the activity and safety of

Objective: The coronary calcium score (CCS) predicts cardiovascular disease risk in individuals with diabetes mellitus, and rate of progression of CCS is an additional and incremental marker of risk. 18 F-sodium fluoride positron emission tomography ( 18 F-NaF PET) detects early and active calcifications within the vasculature. We aimed to ascertain the relationship between 18 F-NaF PET activity and CCS progression in patients with diabetes mellitus. Approach and Results: We identified individuals between 50 and 80 years with diabetes mellitus and no history of clinical coronary artery disease. Those with a CCS ≥10 were invited to undergo 18 F-NaF PET scanning and then repeat CCS >2 years later. 18 F-NaF PET and CCS analysis were performed on a per-coronary and a per-patient level. We compared the proportion of CCS progressors in 18 F-NaF PET–positive versus 18 F-NaF PET–negative coronary arteries. Forty-one participants with 163 coronary arteries underwent follow-up CCS 2.8±0.5 years later. 18 F-NaF PET–positive coronary arteries (n=52) were more likely to be CCS progressors, compared with negative coronary arteries (n=111; 86.5% versus 52.3%, P 18 F-NaF PET–positive disease was an independent predictor of subsequent CCS progression (odds ratio, 2.92 [95% CI, 1.32–6.45], P =0.008). All subjects (100%, 15/15) with ≥2 18 F-NaF–positive coronary arteries progressed in CCS. Conclusions: In subjects with diabetes mellitus, 18 F-NaF PET positivity at baseline, independently predicted the progression of calcifications within the coronary arteries 2.8 years later. These findings suggest 18 F-NaF PET may be a promising technique for earlier identification of patients at higher risk of cardiovascular events.

Recent advances in technology and discovery have led to a key role for nuclear medicine in precision health and individualized patient care. As we enter this era of promise and growth, we need to ensure that our specialty is well equipped to assess, evaluate, and provide evidence for the clinical

Background The rate of increase of coronary arterial calcification score (CCS) on serial CT-scans years apart is a potent marker of cardiovascular risk but identifies risk only after irreversible damage has occurred. Molecular imaging may assist in identifying patients who are at risk of developing severe arterial calcification. Purpose To determine if 18F-Sodium Fluoride Positron Emission Tomography (18F-NaF PET) can predict and anatomically locate the progression of CCS over 2 years. Methods Subjects with diabetes mellitus underwent a baseline 18F-NaF PET scan and a CT CCS. The CT CCS was repeated after 2 years. 18F-NaF PET tracer uptake was measured as the maximum tissue to background ratio (TBRmax) and using a pre-defined cut-off for positivity, arteries were dichotomised into 18F-NaF positive and negative. We compared the change in the CCS between coronary arteries that were positive and negative for 18F-NaF uptake. Results In forty-one participants (mean age 65.0±7.1, male: 63.4%) a total of 163 coronary arteries were included in the analysis. Fifty-two (31.9%) coronary arteries were 18F-NaF positive at baseline and 111 (68.1%) were negative. After 2.8 [2.4–3.2] years follow-up, the TBRmax at baseline correlated with the time-standardised change in the CCS (Spearmans' rho 0.33, p Conclusions 18F-NaF PET activity at baseline is associated with new co-localised calcifications 2.8 years later Figure 1 Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): Royal Perth Hospital Research Foundation

There is currently no treatment for attenuating progression of arterial calcification.154 patients with diabetes mellitus and coronary calcification, as detected using computed tomography (CT), were randomized to one of four treatment groups (placebo/placebo, vitamin-K149 subjects completed follow-up (vitamin-KIn patients with type 2 diabetes, neither vitamin-KACTRN12616000024448.

Cardiovascular disease (CVD) remains a leading cause of death. Preventative therapies that reduce CVD are most effective when targeted to individuals at high risk. Current risk stratification tools have only modest prognostic capabilities, resulting in over-treatment of low-risk individuals and under-treatment of high-risk individuals. Improved methods of CVD risk stratification are required. Molecular imaging offers a novel approach to CVD risk stratification. In particular, 18F-sodium fluoride (18F-NaF) positron emission tomography (PET) has shown promise in the detection of both high-risk atherosclerotic plaque features and vascular calcification activity, which predicts future development of new vascular calcium deposits. The rate of change of coronary calcium scores, measured by serial computed tomography scans over a 2-year period, is a strong predictor of CVD risk. Vascular calcification activity, as measured with 18F-NaF PET, has the potential to provide prognostic information similar to consecutive coronary calcium scoring, with a single-time-point convenience. However, owing to the rapid motion and small size of the coronary arteries, new solutions are required to address the traditional limitations of PET imaging. Two different methods of coronary PET analysis have been independently proposed and here we compare their respective strengths, weaknesses, and the potential for clinical translation.

Background Accurate staging of patients with prostate cancer (PCa) is important for therapeutic decision-making. Relapse after surgery or radiotherapy of curative intent is not uncommon and, in part, represents a failure of staging with current diagnostic imaging techniques to detect disease spread. Prostate-specific membrane antigen (PSMA) positron-emission tomography (PET)/computed tomography (CT) is a new whole-body scanning technique that enables visualization of PCa with high contrast. The hypotheses of this study are that: (i) PSMA-PET/CT has improved diagnostic performance compared with conventional imaging; (ii) PSMA-PET/CT should be used as a first-line diagnostic test for staging; (iii) the improved diagnostic performance of PSMA-PET/CT will result in significant management impact; and (iv) there are economic benefits if PSMA-PET/CT is incorporated into the management algorithm. Objectives and methods The proPSMA trial is a prospective, multicentre study in which patients with untreated high-risk PCa will be randomized to gallium-68-PSMA-11 PET/CT or conventional imaging, consisting of CT of the abdomen/pelvis and bone scintigraphy with single-photon emission CT/CT. Patients eligible for inclusion are those with newly diagnosed PCa with select high-risk features, defined as International Society of Urological Pathology grade group ≥3 (primary Gleason grade 4, or any Gleason grade 5), prostate-specific antigen level ≥20 ng/mL or clinical stage ≥T3. Patients with negative, equivocal or oligometastatic disease on first line-imaging will cross over to receive the other imaging arm. The primary objective is to compare the accuracy of PSMA-PET/CT with that of conventional imaging for detecting nodal or distant metastatic disease. Histopathological, imaging and clinical follow-up at 6 months will define the primary endpoint according to a predefined scoring system. Secondary objectives include comparing management impact, the number of equivocal studies, the incremental value of second-line imaging in patients who cross over, the cost of each imaging strategy, radiation exposure, inter-observer agreement and safety of PSMA-PET/CT. Longer-term follow-up will also assess the prognostic value of a negative PSMA-PET/CT. Outcome and significance This trial will provide data to establish whether PSMA-PET/CT should replace conventional imaging in the primary staging of select high-risk localized PCa, or whether it should be used to provide incremental diagnostic information in selected cases.

The FIG study is a prospective non-randomised study now recruiting up to 210 newly diagnosed GBM participants across ten Australian sites. Study outcomes will address the role of [18F] fluoroethyl-L-tyrosine positron emission tomography (FET-PET) in radiotherapy (RT) planning, evaluation of post-treatment changes versus disease progression and prognostication. We describe here the methodology and preliminary outcomes for site credentialing. Eligible participants with GBM undergo FET-PET imaging at three time-points: FET-PET1-post-operative pre-chemo-RT, FET-PET2 acquired one month post-chemo-RT and FET-PET3 (+/-FDG-PET) triggered when clinical and/or radiological (MRI) progression is suspected. Dynamic and static FET-PET images are analysed qualitatively and quantitatively. Radiotherapy is as per standard care with the treating Radiation Oncologist (RO) blinded to FET-PET1. Site nuclear medicine (NM) physicians are required to delineate a biological target volume (BTV) based on FET-PET1 with hybrid RT volumes derived post-hoc. Pre-trial NM quality assurance comprises certification from the Australasian Radiopharmaceutical Trials Network encompassing FET-PET radiochemistry Quality Control and PET camera calibration. Site and central integrated workflows incorporating multi-modality image registration, target volume/region of interest contouring and analysis have been developed. NM benchmarking involves delineation of FET-PET BTVs in 3 cases with another 3 cases addressing response criteria interpretation harmonized across FET-PET, FDG-PET and MRI. Site ROs complete 3 cases involving standard and hybrid target volume delineation based on pre-derived FET-PET volumes. All NM and RO credentialing cases undergo central expert review. To date, of six sites which have submitted full credentialing data, 19/21 RO and 6/6 planning cases were passed. Of 72 NM cases, 18/72 (25%) required resubmission, primarily related to ensuring standardisation of background regions and time activity curve interpretation. The FIG study will be pivotal in establishing the role of FET-PET in GBM management. The robust NM and RO credentialing program will build capacity and expertise in FET-PET production, acquisition and image interpretation.

Introduction Between 2009 and 2012, 68Ga-somatostatin analogue PET-CT progressively replaced 111In-octreotide scintigraphy for imaging neuroendocrine tumours in WA public hospitals due to published literature demonstrating improved diagnostic accuracy and increased availability. Despite significantly improved sensitivity and specificity, 68Ga-somatostatin analogue PET is currently unfunded in Australia. This study sought to undertake cost analysis of the two modalities in a public hospital setting and to compare them with regard to patient factors such as imaging time and radiation dose. Methods This analysis was based on retrospective clinical data from 95 111In-octreotide scintigraphies performed in 2007 and 2008 at Sir Charles Gairdner (SCGH) and Royal Perth (RPH) hospitals and 219 68Ga-somatostatin analogue PET-CT studies performed in 2013 at SCGH. Whole body effective radiation dose was derived from the radiopharmaceutical and low-dose CT scan. The cost analysis included radiopharmaceutical and imaging costs. Results The median imaging time for an 111In-octreotide scintigraphy was 152 min at SCGH, 100 min at RPH and 20 min for a 68Ga-somatostatin analogue PET-CT scan. The mean effective radiation dose for 111In-octreotide scintigraphy was 18.1 mSv at SCGH and 13.8 mSv at RPH. The effective dose for 68Ga-somatostatin analogue PET-CT was 8.7–10.8 mSv. The average cost of 68Ga-somatostatin analogue PET-CT was four times less than 111In-octreotide scintigraphy. Conclusion 68Ga-somatostatin analogue PET-CT is not only more accurate than 111In-octreotide scintigraphy, this study has also shown that it is significantly less expensive, delivers a lower radiation dose to patients and requires less imaging time for patients and staff. 68Ga-somatostatin PET-CT provides an important combination of both reduced cost and improved clinical care for patients.

68Ga-PSMA PET/CT scanning has been shown to be more sensitive than conventional imaging techniques in patients with prostate cancer. This prospective Australian multicenter study assessed whether 68Ga-PSMA PET/CT imaging affects management intent in patients with primary or recurrent prostate cancer. Methods: Before undertaking 68Ga-PSMA PET imaging, referring medical specialists completed a questionnaire detailing relevant demographic and clinical data as well as their proposed management plan. A separate follow-up questionnaire was completed after the 68Ga-PSMA PET/CT scan results were available to determine whether the management plan would change. Results: A total of 431 patients with prostate cancer from 4 Australian centers had pre- and post-68Ga-PSMA management plans completed. Scans were obtained for primary staging of intermediate- and high-risk disease in 25% of patients and for restaging/biochemical recurrence in 75% of patients. Overall, 68Ga-PSMA PET/CT scanning led to a change in planned management in 51% of patients. The impact was greater in the group of patients with biochemical failure after definitive surgery or radiation treatment (62% change in management intent) than in patients undergoing primary staging (21% change). Imaging with 68Ga-PSMA PET/CT revealed unsuspected disease in the prostate bed in 27% of patients, locoregional lymph nodes in 39%, and distant metastatic disease in 16%. Conclusion:68Ga-PSMA PET/CT scans detect previously unsuspected disease and may influence planned clinical management in a high proportion of patients with prostate cancer. The impact was greater in patients with biochemical recurrence. These results demonstrate the potential clinical value of 68Ga-PSMA PET/CT in management of prostate cancer.

To assess the activity and safety of cabazitaxel chemotherapy vs that of treatment withThe TheraP trial (ANZUP 1603) is an open-label, randomized, stratified, two-arm multicentre phase 2 trial comparing the activity and safety of cabazitaxel chemotherapy vs

Detailed guidelines pertaining to radiological assessment of malignant pleural mesothelioma are currently lacking due to the rarity of the disease, complex morphology, propensity to invade multiple planes simultaneously, and lack of specific recommendations within the radiology community about assessment, reporting, and follow-up. In March 2017, a multidisciplinary meeting of mesothelioma experts was co-sponsored by the National Cancer Institute Thoracic Malignancy Steering Committee, International Association for the Study of Lung Cancer, and the Mesothelioma Applied Research Foundation. One of the outcomes of this conference was the foundation of detailed, multidisciplinary consensus imaging and management guidelines. Here, we present the recommendations for radiologic assessment of malignant pleural mesothelioma in the setting of clinical trial enrollment. We discuss optimization of imaging parameters across modalities, standardized reporting, and response assessment within clinical trials.

18F-fluorocholine positron emission tomography/computed tomography (18F-FCH PET/CT) is an emerging functional imaging technique in the diagnosis and management of hepatocellular carcinoma (HCC). The aim of this study was to assess the ability of a pre- and post-treatment 18F-FCH PET/CT to predict prognosis and treatment response in early-stage HCC. Patients with early- or intermediate-stage HCC planned for locoregional therapy were prospectively enrolled. Baseline demographic and tumor information was collected and baseline and post-treatment 18F-FCH PET/CT performed. Maximum standardized uptake values (SUVmax) were determined for each HCC lesion, and the difference between baseline and post-treatment SUVmax values were compared with progression-free survival outcomes. A total of 29 patients with 39 confirmed HCC lesions were enrolled from a single clinical center. Patients were mostly men (89.7%) with hepatitis C or alcohol-related cirrhosis (65.5%) and early-stage disease (89.7%). Per-patient and per-lesion sensitivity of 18F-FCH PET/CT was 72.4% and 59.0%, respectively. A baseline SUVmax 13 (17.7 vs. 5.1 months; p = 0.006). A > 45% decrease in SUVmax between baseline and post-treatment 18F-FCH PET/CT (“responders”) was associated with a superior mean progression-free survival than a percentage decrease of

Purpose: O-(2-[18F]fluoroethyl)-L-tyrosine (FET), a PET radiotracer of amino acid uptake, has shown potential for diagnosis and treatment planning in patients with glioblastoma (GBM). To improve quantitative assessment of FET PET imaging, we evaluated the repeatability of uptake of this tracer in patients with GBM. Methods: Test-retest FET PET imaging was performed on 8 patients with histologically confirmed GBM, who previously underwent surgical resection of the tumour. Data were acquired according to the protocol of a prospective clinical trial validating FET PET as a clinical tool in GBM. SUVmean, SUVmax and SUV98% metrics were extracted for both test and retest images and used to calculate 95% Bland-Altman limits of agreement (LoA) on lesion-level, as well as on volumes of varying sizes. Impact of healthy brain normalization on repeatability of lesion SUV metrics was evaluated. Results: Tumour LoA were [0.72, 1.46] for SUVmean and SUVtotal, [0.79,1.23] for SUVmax, and [0.80,1.18] for SUV98%. Healthy brain LoA were [0.80,1.25] for SUVmean, [0.80,1.25] for SUVmax, and [0.81,1.23] for SUV98%. Voxel-level SUV LoA were [0.76, 1.32] for tumour volumes and [0.80, 1.25] for healthy brain. When sampled over maximum volume, SUV LoA were [0.90,1.12] for tumour and [0.92,1.08] for healthy brain. Normalization of uptake using healthy brain volumes was found to improve repeatability, but not after normalization volume size of about 15 cm3. Conclusions Advances in Knowledge and Implications for Patient Care: Repeatability of FET PET is comparable to existing tracers such as FDG and FLT. Healthy brain uptake is slightly more repeatable than uptake of tumour volumes. Repeatability was found to increase with sampled volume. SUV normalization between scans using healthy brain uptake should be performed using volumes at least 15 cm3 in size to ensure best imaging repeatability.

TPS177 Background: 177Lu‐PSMA‐617 (LuPSMA) is a novel radionuclide with promising activity and tolerability in metastatic, castration-resistant prostate cancer (mCRPC). Pre-clinical studies have shown that androgen receptor blockade with enzalutamide upregulates PSMA-receptor expression, and that PSMA-receptor blockade increases treatment response to enzalutamide. We hypothesise that concurrent administration of LuPSMA and enzalutamide will be synergistic in mCRPC. The aims of ENZA-p are to determine the activity and safety of LuPSMA and enzalutamide in men with mCRPC at high-risk of early progression on enzalutamide alone; and to identify potential prognostic and predictive biomarkers from imaging, blood, and tissue. Methods: This open-label, randomised, multicentre, phase 2 trial will recruit 160 men with mCRPC. Key eligibility criteria include progression on androgen deprivation therapy, 2 or more high-risk features for early (LDH ≥ULN; ALP ≥ULN; albumin 5 bone metastases; visceral metastases; PSA doubling time 14 days; prior abiraterone), no prior treatment with a novel androgen signalling inhibitor (except abiraterone), no prior chemotherapy for mCRPC, and PSMA-avid disease on positron emission tomography (PET) with 68Ga-PSMA. Participants are randomly assigned (1:1) enzalutamide 160 mg daily or enzalutamide 160 mg daily plus LuPSMA 7.5 GBq on days 15 and 57. Two subsequent doses of Lu-PSMA will be administered if the 68Ga-PSMA PET on day 92 shows persistent PSMA expression in the tumour. Imaging assessments include CT and technetium bone scan at baseline, day 99, then every 12 weeks; 68Ga-PSMA-11 PET at baseline, days 15, 92, and first progression; and 18F FDG PET at baseline and first progression. Translational samples including circulating tumour cells (CTCs), circulating tumour DNA (ctDNA) and biopsies (optional) will be collected at baseline, day 92, and first progression. The primary endpoint is PSA progression-free survival (PSA-PFS). Secondary endpoints include radiological-PFS, PSA-response rate, pain response and PFS, clinical-PFS, overall survival, health related quality of life, adverse events, and cost-effectiveness. Correlative studies include identification of prognostic and predictive biomarkers from 68Ga-PSMA, 18F FDG PET/CT, CTCs, and ctDNA. A sample size of 160 provides 80% power with a 2-sided type 1-error rate of 5% to detect a HR of 0.625 assuming a median PSA-PFS of 5 months with enzalutamide alone. Accrual was 5 on 13 October 2020. ENZA-p is an investigator-initiated, academic trial led by ANZUP in collaboration with the NHMRC Clinical Trials Centre, University of Sydney. Clinical trial information: NCT04419402.

6 Background: TheraP is a randomized phase 2 trial that showed LuPSMA significantly improved the primary endpoint of PSA≥50% reduction (66% vs. 37%) compared to cabazitaxel in men with docetaxel-treated mCRPC. We now report results on other clinical endpoints and PROs reached the pre-specified target of 170 PFS events. Methods: 200 men with mCRPC (median age 72 y, prior enza/abi 91%) and high PSMA-expression by 68Ga-PSMA-11 and no sites of FDG-positive/PSMA-negative disease, were randomly assigned (1:1) to LuPSMA (6-8.5GBq q6wk up to 6 cycles; N = 99) or cabazitaxel (20mg/m2 q3wk up to 10 cycles; N = 101). Secondary endpoints include PSA/radiologic PFS (PCWG3), pain response (≥2 point reduction on McGill-Melzack Present Pain Intensity scale, objective response rate (ORR) (RECIST 1.1), adverse events (CTCAE), PROs (EORTC QLQ-C30) and overall survival (OS). Cut-off date for analysis of 20JUL20. Results: At a median follow-up of 18.4 months, PFS was significantly longer in those assigned Lu-PSMA rather than cabazitaxel (rates at 1y 19% [95%CI 12-27%] vs 3% [1-9%], hazard ratio (HR) 0.63, 95%CI 0.46-0.86; p = 0.003; 173 events). Similar benefit was seen for rPFS (HR 0.64, 95%CI 0.46-0.88; p = 0.007; 160 events) and PSA-PFS (HR 0.60 95%CI 0.44-0.83; p = 0.002; 172 events). ORR in 78 men with measurable disease was significantly greater in the LuPSMA arm (49% vs 24%, RR 2.1, 95%CI 1.1-4.1; p = 0.019). In 90 men with pain at baseline, pain responses occurred in 60% in the Lu-PSMA arm vs 43% for cabazitaxel (RR 1.42, 95%CI 0.84-4.48; p = 0.10). Patient-reported global health status was similar (LuPSMA 64 [95%CI 61-67] vs cabazitaxel 60 [57-64]) with significantly better outcomes reported for fatigue (34 [95%CI 31-37] vs 40 [36-43]), social functioning (79 [76-82] vs 73 [69-77]), insomnia (24 [20-27] vs 29 [25-33]) and diarrhoea (8.3 [5.6-11.0] vs 15.6 [12.6-18.6]) domains. No PRO domains were superior for cabazitaxel. G3-4 AEs were similar to previously reported (33% vs 53%). OS data remains immature (90 deaths). Conclusions: In men with docetaxel-treated mCRPC, LuPSMA is a promising alternative to cabazitaxel with significantly higher activity (PSA≥50%, PFS, ORR), fewer G3-4 AEs, similar effects on global health status, and improvements in some PRO domains. Clinical trial information: NCT03392428.

TPS180 Background: 177Lu‐PSMA-617 (Lu-PSMA) is a radiolabeled small-molecule that binds with high affinity to PSMA enabling highly targeted delivery of beta radiation to prostate cancer cells. In metastatic castration-resistant prostate cancer, Lu-PSMA showed superior activity to Cabazitaxel in the TheraP trial. Although androgen deprivation therapy (ADT) + Docetaxel is a standard of care for de novo high-volume mHNPC, outcomes remain sub-optimal for many patients. We hypothesize that Lu-PSMA prior to docetaxel will achieve a higher undetectable PSA rate at 12 months compared to docetaxel alone in men with newly-diagnosed high-volume mHNPC. Methods: UpFrontPSMA is an open label, randomized, stratified, 2-arm, multi-center, phase 2 clinical trial recruiting 140 patients at 11 Australian centers. Key eligibility criteria include histological diagnosis of prostate cancer within 12 weeks, PSA > 10ng/ml at diagnosis, < 4 weeks on ADT, and high-volume (≥ 4 bone metastases with ≥ 1 outside the axial skeleton, and/or visceral metastases), PSMA-avid disease on 68Ga-PSMA-11 PET/CT with no major discordance on 18FDG-PET/CT. Patients will be randomized 1:1 to the experimental arm (Lu-PSMA 7.5 GBq q6w x 2 cycles followed 6 weeks later by docetaxel 75mg/m2 q3w x 6 cycles), or standard-of-care Arm (docetaxel alone). All patients will receive continuous ADT. Assessments will be done every 3 weeks during study treatment, and then every 6-12 weeks until unequivocal disease progression. CT and whole body bone scan will be performed at baseline and every 12 weeks, 68Ga-PSMA-11 PET/CT at baseline and 12 weeks, and 18FDG-PET/CT at baseline and 12 weeks (if applicable). Correlative samples will include optional tumour tissue (baseline and disease progression), and serial plasma/whole blood collection. The primary endpoint is undetectable PSA (≤ 0.2 ng/ml) at 12 months. Secondary endpoints are safety, time to castration resistance, PSA-progression-free-survival (PSA-PFS), radiographic PFS, radiographic response rates, early PSMA-PET response rates, quality of life and overall survival. Exploratory endpoints are prognostic and predictive value of PET-derived parameters and of biomarkers identified in plasma/whole blood/tumour tissue. The study will have 85% power to reject the null hypothesis if the true 12 month undetectable PSA rate in the experimental Arm is 50%. The power calculation assumes no more than 10 patients (7%) of the 140 patients will be unevaluable or lost to follow-up in 1 year, 5% alpha and two-sided test for proportions. As of October 13, 2020, accrual stands at 4. UpFrontPSMA is an investigator-led, academic trial sponsored by Peter MacCallum Cancer Centre in collaboration with ANZUP Cancer Trials Group with study coordination provided by the Centre for Biostatistics and Clinical Trials (BaCT) Clinical trial information: NCT04343885.

BACKGROUND Data from murine models suggest that CD40 activation may synergize with cytotoxic chemotherapy. We aimed to determine the maximum tolerated dose (MTD) and toxicity profile and to explore immunological biomarkers of the CD40-activating antibody CP-870,893 with cisplatin and pemetrexed in patients with malignant pleural mesothelioma (MPM). PATIENTS AND METHODS Eligible patients had confirmed MPM, ECOG performance status 0-1, and measurable disease. Patients received cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 and CP-870,893 on day 8 of a 21-day cycle for maximum 6 cycles with up to 6 subsequent cycles single-agent CP-870,893. Immune cell subset changes were examined weekly by flow cytometry. RESULTS Fifteen patients were treated at three dose levels. The MTD of CP-870,893 was 0.15 mg/kg, and was exceeded at 0.2 mg/kg with one grade 4 splenic infarction and one grade 3 confusion and hyponatraemia. Cytokine release syndrome (CRS) occurred in most patients (80%) following CP-870,893. Haematological toxicities were consistent with cisplatin and pemetrexed chemotherapy. Six partial responses (40%) and 9 stable disease (53%) as best response were observed. The median overall survival was 16.5 months; the median progression-free survival was 6.3 months. Three patients survived beyond 30 months. CD19+ B cells decreased over 6 cycles of chemoimmunotherapy (P < 0.001) with a concomitant increase in the proportion of CD27+ memory B cells (P < 0.001) and activated CD86+CD27+ memory B cells (P < 0.001), as an immunopharmacodynamic marker of CD40 activation. CONCLUSIONS CP-870,893 with cisplatin and pemetrexed is safe and tolerable at 0.15 mg/kg, although most patients experience CRS. While objective response rates are similar to chemotherapy alone, three patients achieved long-term survival. AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY NUMBER ACTRN12609000294257.

5500 Background: LuPSMA is a radiolabeled small molecule that delivers therapeutic β-radiation to PSMA-expressing tumors. Encouraging efficacy and safety has been shown in non-randomized studies of mCRPC. TheraP is a randomized phase II trial comparing LuPSMA vs cabazitaxel in men with mCRPC progressing after docetaxel. Methods: Men with mCRPC, and imaging with 68Ga-PSMA-11 and 18F-FDG PET/CT that confirmed high PSMA-expression and no sites of FDG-positive/PSMA-negative disease, were randomly assigned (1:1) to LuPSMA (6-8GBq q6weeks up to 6 cycles) vs cabazitaxel (20mg/m2 q3weeks up to 10 cycles); stratified by disease burden (>20 vs ≤20 sites), prior novel antiandrogens (NAA; abiraterone or enzalutamide), and study site. The primary endpoint was PSA response rate (PSA50-RR) defined by ≥50% reduction. Secondary efficacy endpoints included PSA-progression-free survival (PSA-PFS) and overall survival (OS). Data cut-off was 31DEC19 at this first pre-specified analysis. Results: 200 (median age 72 y, prior NAA 91%, >20 lesions 78%) of 291 PET screened men were randomised to LuPSMA (N=99) or cabazitaxel (N=101). 17 patients withdrew or died before receiving study treatment (1 LuPSMA vs 16 cabazitaxel). The PSA50-RR was higher in those assigned LuPSMA than cabazitaxel (65/99 [66%; 95%CI 56-75] vs 37/101 [37%; 95%CI 27-46]; P

18F-Sodium Fluoride Positron Emission Tomography (18F-NaF PET) is a novel molecular imaging modality with promise for use as a risk stratification tool in cardiovascular disease. There are limitations in the analysis of small and rapidly moving coronary arteries using traditional PET technology. We aimed to validate the use of a motion correction algorithm (eMoco) on coronary 18F-NaF PET outcome parameters. Patients admitted with an acute coronary syndrome underwent 18F-NaF PET and computed tomography coronary angiography. 18F-NaF PET data were analyzed using a diastolic reconstruction, an ungated reconstruction and the eMoco reconstruction. Twenty patients underwent 18F-NaF PET imaging and 17 patients had at least one positive lesion that could be used to compare PET reconstruction datasets. eMoco improved noise (the coefficient of variation of the blood pool radiotracer activity) compared to the diastolic dataset (0.09 [0.07 to 0.12] vs 0.14[0.11 to 0.17], p

Background Preliminary studies have reported promising results for the utility of gallium-68 (Ga-68) citrate positron emission tomography-computed tomography (PET-CT) for infection imaging. This technique offers reduced radiation dose to patients, shorter time between injection and imaging and reduced time for image acquisition compared to the 'gold standard' nuclear imaging technique: gallium-67 (Ga-67) citrate scintigraphy. Aims To compare the two imaging modalities to ascertain whether Ga-68 citrate PET-CT is of equivalent diagnostic efficacy for bone and joint infection or pyrexia of unknown origin (PUO) and to assess image quality and reporter confidence. Methods Patients with PUO and suspected bone or joint infection underwent Ga-67 citrate scintigraphy and Ga-68 citrate PET-CT. Participants were followed up for 3 months to record subsequent treatment, investigations and outcome. Results 60 patients were recruited to this multicentre prospective study: 32 for bone and joint infection, 28 for PUO. The results show a sensitivity of 81% for Ga-67 citrate scintigraphy and 69% for Ga-68 citrate PET-CT, a specificity of 79% for Ga-67 citrate and 67% for Ga-68 citrate and were concordant for 76% of the participants. The reporting physician confidence was significantly lower for Ga-68 citrate (P < 0.05), frequently due to prominent physiologic blood pool activity adjacent to the site of infection. Conclusion The sensitivity and specificity of Ga-68 citrate PET-CT were found to be consistently lower than Ga-67 citrate scintigraphy. Additionally, due to the insufficient level of confidence of the reporting physicians for the Ga-68 citrate PET-CT, this modality could not currently be recommended to replace Ga-67 citrate scintigraphy for routine clinical use.

Cardiovascular disease (CVD) remains a leading cause of death. Preventative therapies that reduce CVD are most effective when targeted to individuals at high risk. Current risk stratification tools have only modest prognostic capabilities, resulting in over-treatment of low-risk individuals and under-treatment of high-risk individuals. Improved methods of CVD risk stratification are required. Molecular imaging offers a novel approach to CVD risk stratification. In particular

We describe an unusual presentation of Merkel cell carcinoma (MCC), a rare neuroendocrine cutaneous tumour. A 59-year-old man presented with a 2-week history of dyspnoea on a background of MCC of the left elbow that was diagnosed after an axillary lymph node metastasis had appeared. He was clinically diagnosed with cardiac tamponade and received urgent pericardiocentesis. Thoracic CT imaging revealed a large infiltrating mass within the inferior aspect of the heart, confirmed to be MCC via immunohistochemistry of the pericardial fluid. On review of prior fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) imaging, avid uptake was evident at the corresponding site of disease. This case has several important illustrative aspects, including the clinical manifestations of cardiac metastases, the challenges of MCC histopathological diagnosis and the role of imaging (in particular FDG-PET) in this aggressive disease.

Introduction Single time-point unidimensional tumor thickness measurements define measurable disease for clinical trial inclusion and also constitute a field in the International Association for the Study of Lung Cancer prospective mesothelioma staging database. The modified Response Evaluation Criteria in Solid Tumors (RECIST) guidelines for mesothelioma did not alter the 10-mm minimum tumor measurement recommendation. However, as computed tomography technology has advanced, we sought to examine whether interobserver agreement was acceptable at smaller tumor thickness in mesothelioma. Methods The primary observer selected 170 discrete measurement sites from 105 thoracic computed tomography scans from 50 consenting patients with pleural mesothelioma. Sites represented a range of tumor thickness, lesion morphology, and location. The outer (parietal) tumor margin was marked at each site and presented to five additional observers, who then selected the visceral margin of the tumor to create a line segment that captured tumor thickness. Relative differences among the observer measurements were estimated using a random-effects analysis of variance model to identify the smallest tumor thickness at which linear measurements could be made reliably. Results Systematic bias was observed, with some observers consistently measuring larger or smaller thicknesses than the thickness measured by others. The mean range across all 170 sites was 15.1% of the mean per-site measurement (SD = 9.1%; median range, 13.1%). Measurements acquired at sites with mean tumor thickness less than 7.5 mm demonstrated interobserver variability with a 75th percentile included 20% of the tumor thickness. The 95% confidence interval for relative interobserver measurement differences obtained for mean measurement lengths in the range 5 to 7.5 mm does not exceed the RECIST thresholds. Conclusions This study has implications for the definition of minimally measurable tumor adopted by clinical trial and staging protocols. Although the statistical findings suggest that a reduction in "minimally measurable disease" from 10 mm to 5 or 7.5 mm might be warranted, clinical factors may ultimately dictate the most appropriate definition.

The approach to management of malignant pleural effusions (MPE) has changed over the past few decades. The key goals of MPE management are to relieve patient symptoms using the least invasive means and in the most cost-effective manner. There is now a realization that patient-reported outcome measures should be the primary goal of MPE treatment, and this now is the focus in most clinical trials. Efforts to minimize patient morbidity are complemented by development of less invasive treatments that have mostly replaced the more aggressive surgical approaches of the past. Therapeutic thoracentesis is simple, effective and generally safe, although its benefits may only be temporary. Pleurodesis is the conventional and for a long time the only definitive therapy available. However, the efficacy and safety of talc pleurodesis has been challenged. Indwelling pleural catheter (IPC) drainage is increasingly accepted worldwide and represents a new concept to improve symptoms without necessarily generating pleural symphysis. Recent studies support the effectiveness of IPC treatment and provide reassurance regarding its safety. An unprecedented number of clinical trials are now underway to improve various aspects of MPE care. However, choosing an optimal intervention for MPE in an individual patient remains a challenge due to our limited understanding of the underlying pathophysiology of breathlessness in MPE and a lack of predictors of survival and pleurodesis outcome. This review provides an overview of common pleural interventional procedures used for MPE management, controversies and limitations of current practice, and areas of research most needed to improve practice in future.

TPS138 Background: Disease persistence or relapse following curative-intent surgery or radiotherapy of high-risk prostate cancer is not uncommon. This is attributable, in part, to a failure of accurate staging with diagnostic imaging being insensitive for detection of small volume metastatic disease. Prostate-specific-membrane-antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is a new whole body scanning technique that enables visualisation of prostate cancer with high sensitivity. The hypotheses of this study are that PSMA-PET/CT (a) has improved diagnostic accuracy compared to conventional imaging, (b) should be used as a first-line diagnostic test for staging, (c) the improved diagnostic accuracy will result in significant management impact and (d) provides economic benefits when incorporated into the management algorithm. Methods: This is a 300 patient phase III multi-centre randomized study of patients with untreated high-risk prostate cancer defined by Gleason grade group 3-5, PSA ≥ 20ng/ml or clinical stage ≥ T3. Patients are randomized to Gallium-68-PSMA11 PET/CT or conventional imaging, consisting of computer tomography of the abdomen/pelvis and bone scintigraphy with SPECT/CT. Patients with negative, equivocal or oligometastatic disease cross-over to receive the other imaging arm. The primary objective is to compare the accuracy of PSMA-PET/CT to conventional imaging for detecting nodal or distant metastatic disease. Accuracy is defined by a pre-defined “ground truth” scoring system incorporating histopathologic, imaging and clinical follow-up at six months post randomisation. Secondary objectives include comparing management impact, the number of equivocal studies, the incremental value of second-line imaging in patients who cross-over, health economics, radiation exposure, inter-observer agreement and safety of PSMA-PET/CT. Longer term follow-up will also assess the prognostic value of a negative PSMA-PET/CT. 294 of 300 (98%) patients randomised at time of abstract submission. Clinical trial information: 12617000005358.