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Since first becoming commercially available in 2018, the PET radiopharmaceutical [18F]PSMA‐1007 has been used widely for the diagnosis and staging of prostate cancer. A pharmacopoeia monograph first became available in 2021, prescribing a radiochemical purity specification of >91%, based on analytical results from both TLC (for [18F]fluoride impurity alone) and HPLC (for all other 18F‐impurities). Though this monograph has provided clarity for the quality control testing of [18F]PSMA‐1007, it prescribes a HPLC method using phosphate buffer mobile phase that may present a risk of precipitation of phosphate salts in the HPLC system. The method also requires specialised hardware not immediately available to all laboratories. This work describes the development of a simple, rapid reversed‐phase HPLC method utilising 0.1 M ammonium formate mobile phase for the accurate assessment of both [18F]fluoride impurity and overall radiochemical purity in a single test. This method is especially useful for assessment of product stability over time. A more accurate TLC method for [18F]fluoride impurity is also described. [ABSTRACT FROM AUTHOR]

Introduction: Between 2009 and 2012, 68 Ga-somatostatin analogue PET-CT progressively replaced 111 In-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, 68 Ga-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 95 111 In-octreotide scintigraphies performed in 2007 and 2008 at Sir Charles Gairdner (SCGH) and Royal Perth (RPH) hospitals and 219 68 Ga-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 111 In-octreotide scintigraphy was 152 min at SCGH, 100 min at RPH and 20 min for a 68 Ga-somatostatin analogue PET-CT scan. The mean effective radiation dose for 111 In-octreotide scintigraphy was 18.1 mSv at SCGH and 13.8 mSv at RPH. The effective dose for 68 Ga-somatostatin analogue PET-CT was 8.7-10.8 mSv. The average cost of 68 Ga-somatostatin analogue PET-CT was four times less than 111 In-octreotide scintigraphy.Conclusion: 68 Ga-somatostatin analogue PET-CT is not only more accurate than 111 In-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. 68 Ga-somatostatin PET-CT provides an important combination of both reduced cost and improved clinical care for patients. [ABSTRACT FROM AUTHOR]

The cyclotron-based production of positron-emitting Cu using the (p,α) reaction at 11.7 MeV was investigated starting from natural-zinc (Zn) and enriched Zn-foil targets, as well as its subsequent purification. For Zn, a combination of three resins were assessed to separate Cu from contaminating Ga and Zn. The specific activity of the purified Cu determined using ICP-MS analysis ranged from 143.3 ± 14.3(SD) to 506.2 ± 50.6 MBq/µg while the titration method using p-SCN-Bn-DOTA, p-SCN-Bn-NOTA and diamsar gave variable results (4.7 ± 0.2-412.5 ± 15.3 MBq/µg), with diamsar lying closest to the ICP-MS values. Results suggest that the p-SCN-Bn-DOTA and p-SCN-Bn-NOTA titration methods are significantly affected by the presence of trace-metal contaminants. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to assess the utility of F-fluorocholine (FCH), compared to standard imaging of bone scan (BS) and contrast-enhanced abdominopelvic computed tomography (CT), in patients with castration-resistant prostate carcinoma. Methods: FCH has shown promise as a metabolic imaging agent for prostate carcinoma. Twenty-six patients with castration-resistant prostate carcinoma had FCH, BS and CT imaging within a 2-month period. Individual FCH-positive lesions in bone were compared to the BS and soft tissue lesions were compared to CT. The lesions were then classified as concordant or discordant for the presence or absence of prostate cancer metastases. Discordant bone or soft tissue lesions were followed up with BS or CT, respectively, at 6-month intervals for up to 2 years or until a definitive diagnosis of the discordant lesion could be made. Results: In 13 (50%) of the patients, all lesions identified were concordant; this included 5 patients in whom no lesions could be identified with any imaging modality. In 21 patients, 183 lesions were observed with 149 being concordant and 34 (19%) being discordant (13 patients). Based on follow-up, FCH correctly identified the presence or absence of disease in 27 of 34 lesions, and in 14 cases FCH-positive lesions, not identified on initial imaging, were confirmed as disease on follow-up. The sensitivity, specificity, accuracy, positive predictive and negative predictive values for lesion detection by FCH are 96% (92-98%), 96% (81-99%), 96% (93-97%), 99% (96-100%) and 81% (64-88%), respectively, with 95% confidence intervals shown in parentheses. Conclusion: In this patient cohort, FCH shows good initial concordance (81%) with BS and CT in the detection of metastatic prostate carcinoma. Follow-up of the cases where FCH was initially discordant with subsequent BS or CT shows that FCH was accurate in determining the presence or absence of prostate metastasis in 79% of lesions. While FCH imaging as compared to BS and CT in this patient group has a good sensitivity and specificity for the detection of lesions representing prostate metastasis, further prospective studies are needed to determine its role. [ABSTRACT FROM AUTHOR]

Abstract: The increasing incidence of melanoma and the lack of effective therapy have prompted the development of new vectors, more specific to the pigmented tumor, for early detection and treatment. Targeted agents have to exhibit a rapid, high tumor uptake, long tumor retention and rapid clearance from nontarget organs. This joint work presents results obtained with a new melanoma targeting agent, [125I]-N-(4-dipropylaminobutyl)-4-iodobenzamide or [125I]BZ18. After labeling with a high specific activity, the biodistribution of the compound was investigated in two animal models, the mouse and the sheep. Melanotic tumor retention was observed lasting several days. We visualized the internalization of the agent inside the melanosomes by secondary ion mass spectroscopy imaging, we measured the affinity constants of [125I]BZ18 on a synthetic melanin model and we demonstrated a radiotoxic effect of this labeled agent on B16F0 melanoma cell culture due to its cellular internalization. From this work, [125I]BZ18 appeared a promising melanoma targeting agent in the nuclear medicine field. [Copyright &y& Elsevier]

The aim of this preclinical study was to directly compare [ 18 F]PSMA-1007 with both [ 68 Ga]Ga-PSMA-11 and [ 18 F]AlF-PSMA-11 in mice bearing PSMA-positive tumor xenografts. Uptake was assessed by PET/CT at 1, 2 and 4 h post-injection, and by ex vivo measurement after 4 h. [ 18 F]PSMA-1007 demonstrated the highest tumor uptake of the three tracers. The high uptake in bone for mice injected with [ 18 F]AlF-PSMA-11 suggested rapid in vivo decomposition. This was confirmed by an in vitro plasma stability study., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Introduction: Between 2009 and 2012, 68 Ga-somatostatin analogue PET-CT progressively replaced 111 In-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, 68 Ga-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 95 111 In-octreotide scintigraphies performed in 2007 and 2008 at Sir Charles Gairdner (SCGH) and Royal Perth (RPH) hospitals and 219 68 Ga-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 111 In-octreotide scintigraphy was 152 min at SCGH, 100 min at RPH and 20 min for a 68 Ga-somatostatin analogue PET-CT scan. The mean effective radiation dose for 111 In-octreotide scintigraphy was 18.1 mSv at SCGH and 13.8 mSv at RPH. The effective dose for 68 Ga-somatostatin analogue PET-CT was 8.7-10.8 mSv. The average cost of  68 Ga-somatostatin analogue PET-CT was four times less than 111 In-octreotide scintigraphy., Conclusion: 68 Ga-somatostatin analogue PET-CT is not only more accurate than 111 In-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. 68 Ga-somatostatin PET-CT provides an important combination of both reduced cost and improved clinical care for patients., (© 2017 The Royal Australian and New Zealand College of Radiologists.)

Purpose: The aim of the study was to assess the utility of (18)F-fluorocholine (FCH), compared to standard imaging of bone scan (BS) and contrast-enhanced abdominopelvic computed tomography (CT), in patients with castration-resistant prostate carcinoma., Methods: FCH has shown promise as a metabolic imaging agent for prostate carcinoma. Twenty-six patients with castration-resistant prostate carcinoma had FCH, BS and CT imaging within a 2-month period. Individual FCH-positive lesions in bone were compared to the BS and soft tissue lesions were compared to CT. The lesions were then classified as concordant or discordant for the presence or absence of prostate cancer metastases. Discordant bone or soft tissue lesions were followed up with BS or CT, respectively, at 6-month intervals for up to 2 years or until a definitive diagnosis of the discordant lesion could be made., Results: In 13 (50%) of the patients, all lesions identified were concordant; this included 5 patients in whom no lesions could be identified with any imaging modality. In 21 patients, 183 lesions were observed with 149 being concordant and 34 (19%) being discordant (13 patients). Based on follow-up, FCH correctly identified the presence or absence of disease in 27 of 34 lesions, and in 14 cases FCH-positive lesions, not identified on initial imaging, were confirmed as disease on follow-up. The sensitivity, specificity, accuracy, positive predictive and negative predictive values for lesion detection by FCH are 96% (92-98%), 96% (81-99%), 96% (93-97%), 99% (96-100%) and 81% (64-88%), respectively, with 95% confidence intervals shown in parentheses., Conclusion: In this patient cohort, FCH shows good initial concordance (81%) with BS and CT in the detection of metastatic prostate carcinoma. Follow-up of the cases where FCH was initially discordant with subsequent BS or CT shows that FCH was accurate in determining the presence or absence of prostate metastasis in 79% of lesions. While FCH imaging as compared to BS and CT in this patient group has a good sensitivity and specificity for the detection of lesions representing prostate metastasis, further prospective studies are needed to determine its role.