Casemix and performance of Australian emergency departments: A comparison of major city, regional and remote locations.

OBJECTIVE: EDs are an essential service, and higher rates of presentations per population are seen in regional and remote areas compared to major cities. Australia-wide differences in utilisation and performance remain largely unknown. METHODS: This was a descriptive, retrospective epidemiological study analysing data collected via the National Non-Admitted Patient Emergency Department Care Database managed by the Australian Institute of Health and Welfare. Data from all reporting public hospitals in Australia for the period between 1 July 2018 and 30 June 2019 were analysed. Reporting EDs were geographically categorised using the 2016 Australian Statistical Geography Standard - Remoteness Area. RESULTS: ED presentations for the 293 reporting EDs were 8 352 192 (median 17 904, range 8-113 929), one-third (33.09%, 95% CI 33.06-33.12) were outside major cities. Remote ED presentations were less likely to arrive by ambulance (12.13% [12.01-12.26]; major cites 28.07% [28.03-28.10]; regional 22.55% [22.50-22.60]) but more likely by police/correctional services vehicle (major cities 0.59% [0.58-0.60]; regional 0.71% [0.70-0.72]; remote 1.71% [1.66-1.76]). Presentations to remote EDs were more likely to leave without being attended by a health professional (5.29% [5.21-5.38]; major cities 3.93% [3.92-3.95]; regional 3.53% [3.51-3.55]). A larger proportion of admitted patients stayed at least 8 h in remote (21.83% [21.46-22.20]) and regional (21.52% [21.41-21.62]) EDs compared to major cities (19.82% [19.76-19.88]). CONCLUSIONS: Our study highlights ED utilisation, casemix and performance by location. The differences observed, especially areas of inequity and need for interventions, reiterate that imperative regional and remote EDs are appropriately resourced to support the communities they serve.

18 F-FET PET maximum standard uptake value and WHO tumour classification grade in glioma.

BACKGROUND: In the area of oncology, molecular imaging techniques are becoming increasingly utilised. In neuro-oncology imaging, 18 Fluoro-O-(2) fluoroethyl-L-tyrosine (18 F-FET) is one of the molecular tracers used in positron-emission tomography (PET). Here, we investigated the correlation between maximum standard uptake value (SUV) of 18 F-FET PET and histologically determined World Health Organization (WHO) grade in glioma. PATIENTS AND METHODS: This was a retrospective review of all 18 F-FET PET studies conducted between August 2014 and August 2019. Review was conducted to identify imaging studies performed on patients who had a glioma with histopathology results from surgical resection or biopsy available. RESULTS: A total of 31 18 F-FET PET studies of histologically confirmed glioma were included. WHO grades ranged from II-IV. A positive correlation between maximum SUV uptake on 18 F-FET PET and WHO grade was observed. CONCLUSIONS: There was a correlation identified between WHO glioma grade and maximum SUV on 18 F-FET PET. Further studies are recommended to explore this relationship.

Intracranial Metastasis from Prostate Cancer: Investigation, Incidence, and Imaging Findings in a Large Cohort of Australian Men.

OBJECTIVES: Prostate cancer metastasizing to the brain is remarkably uncommon, with the incidence never having been described in the modern setting. The objective of this study was to determine the incidence and imaging pattern of intracranial metastasis from prostate cancer in a large cohort of Australian men with prostate cancer. MATERIAL AND METHODS: Retrospective review was undertaken of imaging reports for all known prostate cancer patients, who underwent an imaging examination inclusive of the brain, between July 1, 2014, and July 1, 2020. Once an intracranial lesion was identified, all available imaging and clinical notes were reviewed. RESULTS: A total of 5644 imaging examinations which included the brain were identified in 4341 prostate cancer patients. The majority (92.1%) of examinations were 68-Gallium-labeled prostate-specific membrane antigen (68Ga-PSMA) positron emission tomography/computed tomography (PET/CT). Eight patients were identified as having an intracranial metastasis from prostate cancer, yielding an incidence of 0.18%. All patients had a Gleason score of 9 (where known), and the majority of patients (5/8) had a non-acinar variant of prostate cancer. At the time of diagnosis of intracranial metastasis, all patients had extensive metastatic disease. Imaging characteristics of the intracranial lesions were highly variable. CONCLUSION: The incidence of intracranial metastasis in prostate cancer patients has never been well-established. In this study, we determined the incidence as being 0.18%. Given the majority of metastasis constituted unexpected findings on routine restaging 68Ga-PSMA PET/CT, the incidence determined in our study is arguably the most accurate and clinically relevant described to date.

Lu177-PSMA therapy for men with advanced prostate cancer: 18 months survival analysis in a single Australian tertiary institution.

INTRODUCTION: Radioligand therapies, or 'theranostics', have an emerging role in patients with metastatic castration-resistant prostate cancer (mCRPC). Lutetium-177 (Lu), targeting prostate-specific membrane antigen (PSMA), has demonstrated promising outcomes including reduced disease progression and improved overall survival. We aim to determine overall survival demonstrated by our LuPSMA patient cohort to date. METHODS: Kaplan-Meier survival analysis and log-rank test were performed on all LuPSMA therapy patients with at least 12 months of follow-up data available (n = 68). Comparison across patients was made based on several variables including the baseline characteristics of prostate-specific antigen (PSA) level, maximum standard uptake value (SUVmax ) and metastasis site and by biochemical response. RESULTS: The 18-month overall survival estimate for the patient cohort was 63.8%. Patients with baseline serum PSA <20 µg/L had a greater 18-month survival estimate (79.9%) compared to PSA ≥20 µg/L (53.8%; P < 0.05). Patients with an SUVmax  >15 had an 18-month survival estimate of 56.0%, compared to 38.0% in patients with SUVmax  ≤15 (P < 0.05). No significant difference in overall survival was observed by metastasis site. Both a decrease in PSA after two LuPSMA therapy cycles and the maximum response over the treatment course being a decline in PSA were indicative of greater overall survival (P < 0.01 and P < 0.001 respectively). CONCLUSION: Our study reported an 18-month overall survival of 64% in patients with mCRPC who have undergone LuPSMA therapy. Our study identified that baseline serum PSA, SUVmax and biochemical response to treatment are prognostic markers for increased overall survival.

Solitary rib lesions showing prostate-specific membrane antigen (PSMA) uptake in pre-treatment staging 68 Ga-PSMA-11 positron emission tomography scans for men with prostate cancer: benign or malignant?

OBJECTIVES: To determine the proportion of solitary rib lesions on pre-treatment 68 Gallium-labelled prostate-specific membrane antigen (PSMA)/computed tomography (CT) scans in men with prostate cancer that are malignant and examine any predictive factors. PATIENTS AND METHODS: This retrospective single tertiary referral institution cohort study of men reviewed the results of 68 Ga-PSMA-11 positron emission tomography (PET)/CT scans performed for primary staging prior to treatment of prostate cancer from July 2014 to September 2019. Men with PSMA uptake outside the prostate in only the rib lesion were included. A solitary rib lesion was considered to be malignant if it increased in size on follow-up imaging. A lesion was considered benign if the prostate-specific antigen (PSA) level remained <0.1 µg/L following a radical prostatectomy (RP), <2 µg/L above nadir following radiotherapy (RT) as per the Phoenix criteria, histology was benign on rib biopsy, or follow-up imaging showed no growth of the rib lesion. If a lesion did not meet these criteria it was considered indeterminate. RESULTS: A total of 62 men had PSMA uptake in a solitary rib lesion; 54 went on to have RPs and eight underwent RT. In all, 61 of the men (98.4%) met the criteria for a benign rib lesion. Only one man had a false-negative malignant lesion. This man had a rib lesion with a low maximum standardised uptake value (SUVmax ) of 2.21 reported as benign, but the postoperative PSA level was 0.67 µg/L and the rib lesion progressed on follow-up imaging, with development of widespread metastases. Of the benign rib lesions, there were four false positives reported as possible metastases. Three had percutaneous rib biopsies, two of which came back with benign histology and one was indeterminate. The indeterminate biopsy patient had a RP and his postoperative PSA level was <0.1 µg/L. A total of 43 (69.4%) men with benign rib lesions had a SUVmax greater than the SUVmax of the malignant lesion. CONCLUSION: To our knowledge, this is the first cohort study of men with PSMA-avid solitary rib lesions on pre-treatment 68 Ga-PSMA PET/CT staging scans for prostate cancer. Our results indicate that the vast majority of these lesions have low-intensity uptake and are benign. Intervention to confirm this is not usually required.

Prostate penile metastasis: Incidence and imaging pattern on 68 Ga-PSMA PET/CT.

BACKGROUND: Prostate cancer commonly metastasises to bone and regional lymphatics and more rarely to locations such as the brain, skin and penis. Gallium-68 prostate-specific membrane antigen (68 Ga-PSMA) positron emission tomography/computed tomography (PET/CT) has widely become the routine imaging modality for prostate cancer staging and re-staging in Australia. The aim of this study was to retrospectively review all 68 Ga-PSMA PET/CT examinations performed to date at our institution to determine the frequency of penile metastases. METHODS: A total of 4860 68 Ga-PSMA PET/CT examinations were performed between 16/07/2014 and 31/10/2019. Radiology reports for each examination were filtered to identify those with the words 'penis' or 'penile'. Once identified, relevant reports and images were individually reviewed to confirm the presence of a PSMA-avid penile lesion. RESULTS: The incidence of penile metastasis of prostate cancer observed in this study was 0.1% with six examinations identified as having PSMA-avid penile lesions in five prostate cancer patients (age range: 71-88 years). The patients had a 1-8 year history of prostate cancer with varying severity of disease. Appearance of PSMA-avidity varied between single focal lesion, multiple focal lesions and diffuse lesion. CONCLUSIONS: An incidence of 0.1% in our study confirms the rarity of penile metastases of prostate cancer. Although rare, identification of prostate cancer penile metastases is important for appropriate treatment management and symptom-relief.

What does coal mine dust lung disease look like? A radiological review following re-identification in Queensland.

INTRODUCTION: Coal mine dust lung disease (CMDLD), including the pneumoconioses, dust-related diffuse fibrosis (DDF) and chronic obstructive pulmonary disease (COPD), are occupational lung diseases attributed to respirable coal mine dust. Following the re-identification of CMDLD in Queensland in 2015, we undertook a case series to understand their radiological presentation. METHODS: Chest radiographs and high-resolution computed tomography (HRCT) were retrospectively reviewed for 79 male individuals diagnosed by a respiratory physician with a CMDLD since 2015. Radiological findings were characterised as per the International Labour Office Classification System (ILO system) and the International Classification of HRCT for Occupational and Environmental Respiratory Diseases (ICOERD). RESULTS: Subjects with pneumoconiosis (n = 56) demonstrated widespread opacities with bilateral upper zone predominance. The majority of the lung was impacted, with 72% and 79% of zones demonstrating opacities on chest radiograph and HRCT, respectively. Most pneumoconiosis subjects (71%) demonstrated ILO category 1 disease, while 29% had advanced disease (ILO grades ≥ 2/1). A high proportion (81%) of pneumoconiosis subjects demonstrated at least one radiological feature associated with exposure to respirable crystalline silica (RCS). DDF subjects (n = 5) had radiologically severe disease (mean ILO 2/1) with lower zone-predominant irregular opacities. Widespread emphysema, with no zone dominance, was the key radiological feature in those with COPD (n = 18). CONCLUSION: Radiological findings of particular interest included the high burden of opacities observed and the presence of RCS-associated features in the majority of subjects. Radiologists are at the front line in occupational lung disease screening/diagnosis and must be aware of the imaging spectrum.