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Purpose:Tumor hypoxia fuels an aggressive tumor phenotype and confers resistance to anticancer treatments. We conducted a clinical trial to determine whether the antimalarial drug atovaquone, a known mitochondrial inhibitor, reduces hypoxia in non–small cell lung cancer (NSCLC).Patients and Methods:Patients with NSCLC scheduled for surgery were recruited sequentially into two cohorts: cohort 1 received oral atovaquone at the standard clinical dose of 750 mg twice daily, while cohort 2 did not. Primary imaging endpoint was change in tumor hypoxic volume (HV) measured by hypoxia PET-CT. Intercohort comparison of hypoxia gene expression signatures using RNA sequencing from resected tumors was performed.Results:Thirty patients were evaluable for hypoxia PET-CT analysis, 15 per cohort. Median treatment duration was 12 days. Eleven (73.3%) atovaquone-treated patients had meaningful HV reduction, with median change −28% [95% confidence interval (CI), −58.2 to −4.4]. In contrast, median change in untreated patients was +15.5% (95% CI, −6.5 to 35.5). Linear regression estimated the expected mean HV was 55% (95% CI, 24%–74%) lower in cohort 1 compared with cohort 2 (P = 0.004), adjusting for cohort, tumor volume, and baseline HV. A key pharmacodynamics endpoint was reduction in hypoxia-regulated genes, which were significantly downregulated in atovaquone-treated tumors. Data from multiple additional measures of tumor hypoxia and perfusion are presented. No atovaquone-related adverse events were reported.Conclusions:This is the first clinical evidence that targeting tumor mitochondrial metabolism can reduce hypoxia and produce relevant antitumor effects at the mRNA level. Repurposing atovaquone for this purpose may improve treatment outcomes for NSCLC.

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Background 18F-fluciclovine is a synthetic amino acid positron emission tomography (PET) radiotracer that is approved for use in prostate cancer. In this clinical study, we characterised the kinetic model best describing the uptake of 18F-fluciclovine in breast cancer and assessed differences in tracer kinetics and static parameters for different breast cancer receptor subtypes and tumour grades. Methods Thirty-nine patients with pathologically proven breast cancer underwent 20-min dynamic PET/computed tomography imaging following the administration of 18F-fluciclovine. Uptake into primary breast tumours was evaluated using one- and two-tissue reversible compartmental kinetic models and static parameters. Results A reversible one-tissue compartment model was shown to best describe tracer uptake in breast cancer. No significant differences were seen in kinetic or static parameters for different tumour receptor subtypes or grades. Kinetic and static parameters showed a good correlation. Conclusions 18F-fluciclovine has potential in the imaging of primary breast cancer, but kinetic analysis may not have additional value over static measures of tracer uptake. Clinical Trial Registration NCT03036943.

The aim of this guideline is to provide standards for the recommendation, performance, interpretation, and reporting of [18F]Fluciclovine PET/CT for prostate cancer imaging. These recommendations will help to improve accuracy, precision, and repeatability of [18F]Fluciclovine PET/CT for prostate cancer essentially needed for implementation of this modality in science and routine clinical practice.

INTRODUCTION Following treatment of brain metastases, which can affect up to 40% of patients with cancer, patients will typically be closely monitored with serial brain magnetic resonance imaging (MRI) owing to the high likelihood of recurrence. The recommended follow-up modalities (CE-T1-weighted and FLAIR/T2-weighted MRI) have poor specificity, meaning that differentiation of true disease from treatment-related changes such as radiation necrosis can be difficult. Recent pilot studies have reported amino acid PET radiopharmaceutical, 18F-fluciclovine, to be potentially useful in discriminating tumor recurrence from treatment-related changes. This may potentially aid physicians in making confident diagnoses and inform subsequent treatment plans. METHODS REVELATE (NCT04410133) will evaluate the diagnostic performance of 18F-fluciclovine PET (read with conventional MRI for anatomical reference) for the detection of recurrent brain metastases in patients for whom MRI is equivocal. This multicenter, phase 3, prospective, open-label trial aims to enroll approximately 150 subjects from across 19 US sites with solid tumor brain metastases who have undergone radiation therapy, if they have a lesion considered equivocal on MRI that requires further confirmatory diagnostic procedures (either biopsy/neurosurgical intervention or clinical follow-up). Patients will undergo 18F-fluciclovine PET

Purpose: Tumor hypoxia fuels an aggressive tumor phenotype and confers resistance to anticancer treatments. We conducted a clinical trial to determine whether the antimalarial drug atovaquone, a known mitochondrial inhibitor, reduces hypoxia in non–small cell lung cancer (NSCLC). Patients and Methods: Patients with NSCLC scheduled for surgery were recruited sequentially into two cohorts: cohort 1 received oral atovaquone at the standard clinical dose of 750 mg twice daily, while cohort 2 did not. Primary imaging endpoint was change in tumor hypoxic volume (HV) measured by hypoxia PET-CT. Intercohort comparison of hypoxia gene expression signatures using RNA sequencing from resected tumors was performed. Results: Thirty patients were evaluable for hypoxia PET-CT analysis, 15 per cohort. Median treatment duration was 12 days. Eleven (73.3%) atovaquone-treated patients had meaningful HV reduction, with median change −28% [95% confidence interval (CI), −58.2 to −4.4]. In contrast, median change in untreated patients was +15.5% (95% CI, −6.5 to 35.5). Linear regression estimated the expected mean HV was 55% (95% CI, 24%–74%) lower in cohort 1 compared with cohort 2 (P = 0.004), adjusting for cohort, tumor volume, and baseline HV. A key pharmacodynamics endpoint was reduction in hypoxia-regulated genes, which were significantly downregulated in atovaquone-treated tumors. Data from multiple additional measures of tumor hypoxia and perfusion are presented. No atovaquone-related adverse events were reported. Conclusions: This is the first clinical evidence that targeting tumor mitochondrial metabolism can reduce hypoxia and produce relevant antitumor effects at the mRNA level. Repurposing atovaquone for this purpose may improve treatment outcomes for NSCLC.

Background Brain metastases occur in up to 40% of patients with cancer and are associated with poor prognosis and considerable levels of recurrence. Consequently, close follow-up with serial brain MRI is performed post-treatment to monitor for recurrent disease. Although conventional MRI (CE-T1-weighted and FLAIR/T2-weighted) is the recommended follow-up modality, it has poor specificity with limited ability to differentiate between true disease recurrence and treatment-related changes such as radiation necrosis. Therefore, alternative imaging options are sought in order to help physicians confidently diagnose treatment-related changes and thus reliably stratify the risk of continuation of a therapeutic regimen, especially given the morbidity associated with current treatments. Amino acid PET imaging agent, 18F-fluciclovine, has increased uptake in brain tumors relative to normal tissue and may be useful for detecting recurrent brain metastases. Methods NCT04410133 is a prospective, open-label, single-arm, single-dose (185 MBq ±20%) study with a primary objective to confirm the diagnostic performance of 18F-fluciclovine PET (read with conventional MRI for anatomical reference) for detection of recurrent brain metastases where MRI is equivocal. Approximately 150 subjects with solid tumor brain metastases who have undergone radiation therapy will be enrolled in this multicenter trial (~18 US sites) if they have a lesion considered equivocal on MRI that requires further confirmatory diagnostic procedures such as biopsy/neurosurgical intervention or clinical follow-up. Subjects will undergo 18F-fluciclovine PET

Over the last two decades, the exponential use of CT in the assessment of the urological patient has been fuelled by the advent of multidetector thin slice CT and supersession of intravenous urography by CT urography. The latter may be considered as a one-stop imaging investigation for haematuria, with increased detection of urinary tract cancers and urolithiasis alike. Multi-planar reformats are made possible with the use of thin slices, allowing clear delineation of other pathologies such as urinary tract injury, and can aid PCNL planning. Outside of this spectrum, unenhanced CT of the kidneys, ureters, and bladder has established its role in assessment of the patient with symptoms of renal colic, with the scope to detect pathology outside of the urinary tract. Renal CT has been developed for the characterization of renal masses, accompanied by the now well-established Bosniak renal cyst classification system.

Background and objective: Poor transition to practice during the first year of graduate nurses' employment causes compromised patient care and a high staff turnover. Globally, as the world grapples with an ageing population and increasing healthcare demands, it is imperative to retain newly qualified Registered Nurses to sustain the nursing workforce. Objectives: To explore newly qualified Registered Nurses on their transition to practice journey during their first six months of employment.Methods: Design: A qualitative descriptive design. Settings: A large metropolitan public hospital in Singapore. Participants: A purposive sample of eleven newly qualified Registered Nurses with six months of graduate working experience. Methods: One-to-one semi-structured interviews were conducted, audio-taped and transcribed verbatim. Thematic analysis was employed in this study.Results: Three themes emerged from the data analysis: personal adaptations, professional adaptations and organisational adaptations. Subthemes of personal adaptations include a new experience, seeking help and coping with transition. Under professional adaptations, the subthemes are accountability, coordination, interprofessional relationships and knowledge. Subthemes of organisational adaptations are staff support, working environment and transition to practice programme.Conclusions: The findings emphasized the importance of establishing responsibilities, performance expectations and appropriate workplace behaviors guidelines, and to bridge the gap between transition to practice programme and preceptorship is also necessary.

Computed tomography (CT) has increased in use exponentially for the assessment of patients with renal tract pathology. This has been promoted by the availability of multidetector thin-slice CT so that intravenous urography has been superseded by CT urography. The latter may be considered as a ‘one-stop’ imaging investigation for haematuria, with increased detection of both urinary tract cancers and urolithiasis. Multiplanar reformats are made possible with the use of thin slices, allowing clear delineation of other pathologies such as urinary tract injury. In the transplant recipient, protocols have been developed for the assessment of more immediate complications such as thrombotic and stenotic disease. During follow-up, CT continues to inform the management of post-transplant lymphoproliferative disorder and other immunosuppressant-related complications. Unenhanced CT of the urinary tract has established its role in assessment of patients with renal colic, with the ability to detect pathology outside of the urinary tract. Renal CT has been developed for the characterization of renal masses, accompanied by the now well-established Bosniak renal cyst classification system. As the usefulness of CT increases, clear awareness of safety issues has to be maintained. These include the administration of intravenous iodinated contrast medium in higher-risk patient groups, particularly those with renal impairment. The radiation burden that comes with CT poses an added risk to the patient that should not be ignored. This necessitates clear referral guidelines for its use, which should be applied in careful balance with the global assessment of the patient.

There is growing interest in the anticancer effect of the diabetes drug, metformin, and over 100 clinical trials are underway worldwide. However it is still not determined as to whether metformin has significant direct effects on cancer cells or solely indirect effects via modulation of host metabolism. We recruited 41 non-diabetic patients with primary breast cancer to a neoadjuvant window trial. Patients received an escalating dose of metformin (500mg up to 1500mg) for 2 weeks with pre- and post-metformin pharmacodynamic assessments including, dynamic 18F-FDG PET-CT scans, serum metabolic markers, and tumour biopsies for whole transcriptome RNASeq, tumour metabolomics and immunohistochemistry. Assessment of tumour FDG kinetics using a classic 2-tissue compartment model with three rate constants showed a 1.3 fold change (FC) post-metformin in the composite 18F-FDG flux constant, Kflux (p = 0.041, on paired t-test). There was a non-statistically significant 1.1 fold increase in the variable, metabolic rate of glucose utilization (MRglu) (p = 0.141). Mass spectrometry analysis revealed a decrease in intra-tumoral levels of the short-chain acyl-carnitines, propionylcarnitine (FC -0.50, p = 0.039) and acetylycarnitine (FC -0.40, p = 0.046) consistent with inhibition of fatty acid oxidation (wilcoxon rank test). This effect on fatty acid oxidation was validated in pre-clinical in vitro and in vivo breast cancer cell line models. There was a statistically significant positive correlation between the actual difference in Kflux and intratumoral levels of acetylcarnitine (p = 0.012, Spearman's rank test). Small but consistent falls in the levels of serum glucose (p = 0.032), c-peptide (p = 0.001), insulin (p = 0.005), IGF1 (p = 0.048) and IGF2 (p = 0.040) were observed following metformin treatment (paired t-test) but there was no correlation with change in Kflux or short chain acyl-carnitine levels. Pathway annotation analysis using GeneCodis revealed several pathways associated with mitochondrial and fatty acid metabolism that were upregulated. Immunohistochemical intratumoral nuclear expression of pAMPK increased 1.5 fold (p = 0.037, paired t-test) but this did not correlate with change in Kflux or levels of short-chain acyl-carnitines. Peak serum metformin levels correlated with intratumoral metformin levels (p = 0.012, Spearman's rank test) but did not correlate with change in Kflux or short-chain acyl-carnitine levels. Our data shows that metformin treatment alters FDG kinetics, inhibits fatty acid oxidation and leads to altered gene expression in the mitochondrial (nuclear encoded) transcriptome but that these effects do not correlate with changes in host metabolism. This data provides strong evidence that metformin has a direct effect on breast cancer metabolism at clinical doses. Citation Format: Simon Lord, Daniel Liu, Syed Haider, Edoardo Gaude, Eugene Teoh, Patel Neel, Qifeng Zhang, Fergus Gleeson, Michael Wakelam, Christian Frezza, Francesca Buffa, Fenwick John, Adrian Harris. Integrating dynamic 18F-FDG PET-CT, tumor metabolomics and functional genomics to understand metformin's pharmacodynamic effects in breast cancer: results of a phase 0 clinical trial. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-200.

The failure of newly qualified Registered Nurses to be appropriately transitioned into the new practice has been mentioned in numerous nursing literatures. Along with the need to decrease turnover rates, increase satisfaction rate of nurses and improve patient outcomes, nursing educators in Singapore are interested in the experiences of these nurses in their transition to practice journey. In this paper, the author attempts to critically review qualitative research conducted in that area to identify why nurses are leaving the profession and how nursing educators in Singapore can reduce stress and uncertainty in the newly qualified Registered Nurses during their transition to practice journey. In conducting a qualitative literature review, the author aims to explore interpretation of these nurses' subjective experiences and description of their social context, ultimately paying attention to lay knowledge as human behaviour is context specific rather than being represented in the quantitative form.