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Background The SARS-Cov-2 Omicron variant demonstrates rapid spread but reduced disease severity. Studies evaluating lung imaging findings of Omicron infection versus non-Omicron infection remain lacking. Purpose To compare the Omicron variant with the SARS-CoV-2 Delta variant according to their chest CT radiologic pattern, biochemical parameters, clinical severity, and hospital outcomes after adjusting for vaccination status. Materials and Methods This retrospective study included hospitalized adult patients with reverse transcriptase-polymerase chain reaction test results positive for SARS-CoV-2, with CT pulmonary angiography performed within 7 days of admission between December 1, 2021, and January 14, 2022. Multiple readers performed blinded radiologic analyses that included RSNA CT classification, chest CT severity score (CTSS) (range, 0 [least severe] to 25 [most severe]), and CT imaging features, including bronchial wall thickening. Results A total of 106 patients (Delta group, n = 66; Omicron group, n = 40) were evaluated (overall mean age, 58 years ± 18 [SD]; 58 men). In the Omicron group, 37% of CT pulmonary angiograms (15 of 40 patients) were categorized as normal compared with 15% (10 of 66 patients) of angiograms in the Delta group (P = .016). A generalized linear model was used to control for confounding variables, including vaccination status, and Omicron infection was associated with a CTSS that was 7.2 points lower than that associated with Delta infection (ß = -7.2; 95% CI: -9.9, -4.5; P < .001). Bronchial wall thickening was more common with Omicron infection than with Delta infection (odds ratio [OR], 2.4; 95% CI: 1.01, 5.92; P = .04). A booster shot was associated with a protective effect for chest infection (median CTSS, 5; IQR, 0-11) when compared with unvaccinated individuals (median CTSS, 11; IQR, 7.5-14.0) (P = .03). The Delta variant was associated with a higher OR of severe disease (OR, 4.6; 95% CI: 1.2, 26; P = .01) and admission to a critical care unit (OR, 7.0; 95% CI: 1.5, 66; P = .004) when compared with the Omicron variant. Conclusion The SARS-CoV-2 Omicron variant was associated with fewer and less severe changes on chest CT images compared with the Delta variant. Patients with Omicron infection had greater frequency of bronchial wall thickening but less severe disease and improved hospital outcomes when compared with patients with Delta infection. © RSNA, 2022 Online supplemental material is available for this article.
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COVID-19 , Hepatitis D , Adult , Male , Humans , Middle Aged , SARS-CoV-2 , Retrospective Studies , Hospitals , Tomography, X-Ray ComputedABSTRACT
Bleomycin, a cytotoxic chemotherapy agent, forms a key component of curative regimens for lymphoma and germ cell tumours. It can be associated with severe toxicity, long-term complications and even death in extreme cases. There is a lack of evidence or consensus on how to prevent and monitor bleomycin toxicity. We surveyed 63 germ cell cancer physicians from 32 cancer centres across the UK to understand their approach to using bleomycin. Subsequent guideline development was based upon current practice, best available published evidence and expert consensus. We observed heterogeneity in practice in the following areas: monitoring; route of administration; contraindications to use; baseline and follow-up investigations performed, and advice given to patients. A best-practice clinical guideline for the use of bleomycin in the treatment of germ cell tumours has been developed and includes recommendations regarding baseline investigations, the use of pulmonary function tests, route of administration, monitoring and patient advice. It is likely that existing heterogeneity in clinical practice of bleomycin prescribing has significant economic, safety and patient experience implications. The development of an evidence-based consensus guideline was supported by 93% of survey participants and aims to address these issues and homogenise practice across the UK.
Subject(s)
Antibiotics, Antineoplastic/administration & dosage , Bleomycin/administration & dosage , Neoplasms, Germ Cell and Embryonal/drug therapy , Testicular Neoplasms/drug therapy , Antibiotics, Antineoplastic/adverse effects , Antibiotics, Antineoplastic/pharmacology , Bleomycin/adverse effects , Bleomycin/pharmacology , Clinical Trials as Topic , Consensus , Evidence-Based Medicine , Humans , Male , Neoplasms, Germ Cell and Embryonal/physiopathology , Respiratory Function Tests , Testicular Neoplasms/physiopathology , United KingdomABSTRACT
The 5-year survival of patients with pancreatic cancer is poor and, despite oncological advances over the past two decades, has not significantly improved. However, there have been several surgical and oncological advances which have improved morbidity and mortality in surgery and more efficacious chemotherapy regimens, resulting in a better patient experience and an increase in survival by a number of months. Most patients have a tumour at the head of the pancreas and those with resectable disease undergo a pancreaticoduodenectomy, which can be performed laparoscopically. Those who have a pancreatic resection have an increased survival in comparison with those receiving oncological treatment only; however, only a quarter of patients have resectable disease at diagnosis. Some centres are now performing venous resections and/or arterial resections in order to increase the number of patients eligible for curative surgery. Innovative techniques using ablation technologies to downstage tumours for resection are also being investigated. After surgery, all patients should be offered adjuvant gemcitabine-based chemotherapy. Those with locally advanced tumours not suitable for surgery should be offered FOLFIRINOX chemotherapy, after which the tumour may be suitable for surgical resection. The use of radiotherapy in this group of patients is controversial but offered by a few centres. Patients with metastatic disease at diagnosis should also be offered FOLFIRINOX chemotherapy, which can improve survival by a few months. As our knowledge of the tumour biology of pancreatic cancer progresses, a number of new agents targeting specific genes and proteins are under investigation and there is hope that median survival will continue to improve over the next decade.
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Adenocarcinoma/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pancreatic Neoplasms/therapy , Pancreaticoduodenectomy , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Chemotherapy, Adjuvant , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Humans , Organoplatinum Compounds/administration & dosage , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/pathology , Practice Guidelines as Topic , Prognosis , Treatment Outcome , GemcitabineABSTRACT
Background. Ciliated hepatic foregut cysts (CHFCs) are uncommon cystic lesions within the liver. CHFCs can undergo a malignant transformation to form a primary squamous cell carcinoma of the liver. The true incidence and natural history of CHFCs is unknown and the risk of malignant transformation is unclear. We present a single centre's experience of CFHC management. Methods. A retrospective review of a departmental database identified all patients with CHFCs over a 4 year time period. Patients with CHFCs confirmed on histological assessment or suspected on radiological imaging were included in this study. Clinical information regarding patient demographics, symptomatic presentation, surgical management and histopathological features were noted. The radiological characteristics of CHFCs were recorded and the malignant transformation rate was calculated. Results. 15 patients with CHFC were identified (7 histologically confirmed and 8 radiologically suspected cases). All patients were asymptomatic and the CHFCs were incidental findings. No CHFC developed an interval change in cyst features or underwent a malignant transformation during follow up. MRI serves as the most sensitive modality to diagnose CHFC. Conclusions. CHFCs may be more prevalent than previously reported. Definitive management should encompass a patient centred discussion regarding the merits of long term follow up with serial imaging versus resection on an individual basis once CHFC is diagnosed.
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Cysts , Liver Diseases , Humans , Cilia/pathology , Liver Diseases/pathology , Cysts/pathology , Cell Transformation, Neoplastic/pathologyABSTRACT
BACKGROUND: Pleural biopsy findings offer greater diagnostic sensitivity in malignant pleural effusions compared with pleural fluid. The adequacy of pleural biopsy techniques in achieving molecular marker status has not been studied, and such information (termed "actionable" histology) is critical in providing a rational, efficient, and evidence-based approach to diagnostic investigation. RESEARCH QUESTION: What is the adequacy of various pleural biopsy techniques at providing adequate molecular diagnostic information to guide treatment in malignant pleural effusions? STUDY DESIGN AND METHODS: This study analyzed anonymized data on 183 patients from four sites across three countries in whom pleural biopsy results had confirmed a malignant diagnosis and molecular profiling was relevant for the diagnosed cancer type. The primary outcome measure was adequacy of pleural biopsy for achieving molecular marker status. Secondary outcomes included clinical factors predictive of achieving a molecular diagnosis. RESULTS: The median age of patients was 71 years (interquartile range, 63-78 years), with 92 of 183 (50%) male. Of the 183 procedures, 105 (57%) were local anesthetic thoracoscopies (LAT), 12 (7%) were CT scan guided, and 66 (36%) were ultrasound guided. Successful molecular marker analysis was associated with mode of biopsy, with LAT having the highest yield and ultrasound-guided biopsy the lowest (LAT vs CT scan guided vs ultrasound guided: LAT yield, 95%; CT scan guided, 86%; and ultrasound guided, 77% [P = .004]). Biopsy technique and size of biopsy sample were independently associated with successful molecular marker analysis. LAT had an adjusted OR for successful diagnosis of 30.16 (95% CI, 3.15-288.56; P = .003) and biopsy sample size an OR of 1.18 (95% CI, 1.02-1.37) per millimeter increase in tissue sample size (P < .03). INTERPRETATION: Although previous studies have shown comparable overall diagnostic yields, in the modern era of targeted therapies, this study found that LAT offers far superior results to image-guided techniques at achieving molecular profiling and remains the optimal diagnostic tool.
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Pleural Effusion, Malignant , Pleural Effusion , Humans , Male , Middle Aged , Aged , Female , Retrospective Studies , Pleura/pathology , Image-Guided Biopsy/methods , Ultrasonography , Pleural Effusion/pathologyABSTRACT
BACKGROUND: Direct evaluation of vascular inflammation in patients with COVID-19 would facilitate more efficient trials of new treatments and identify patients at risk of long-term complications who might respond to treatment. We aimed to develop a novel artificial intelligence (AI)-assisted image analysis platform that quantifies cytokine-driven vascular inflammation from routine CT angiograms, and sought to validate its prognostic value in COVID-19. METHODS: For this prospective outcomes validation study, we developed a radiotranscriptomic platform that uses RNA sequencing data from human internal mammary artery biopsies to develop novel radiomic signatures of vascular inflammation from CT angiography images. We then used this platform to train a radiotranscriptomic signature (C19-RS), derived from the perivascular space around the aorta and the internal mammary artery, to best describe cytokine-driven vascular inflammation. The prognostic value of C19-RS was validated externally in 435 patients (331 from study arm 3 and 104 from study arm 4) admitted to hospital with or without COVID-19, undergoing clinically indicated pulmonary CT angiography, in three UK National Health Service (NHS) trusts (Oxford, Leicester, and Bath). We evaluated the diagnostic and prognostic value of C19-RS for death in hospital due to COVID-19, did sensitivity analyses based on dexamethasone treatment, and investigated the correlation of C19-RS with systemic transcriptomic changes. FINDINGS: Patients with COVID-19 had higher C19-RS than those without (adjusted odds ratio [OR] 2·97 [95% CI 1·43-6·27], p=0·0038), and those infected with the B.1.1.7 (alpha) SARS-CoV-2 variant had higher C19-RS values than those infected with the wild-type SARS-CoV-2 variant (adjusted OR 1·89 [95% CI 1·17-3·20] per SD, p=0·012). C19-RS had prognostic value for in-hospital mortality in COVID-19 in two testing cohorts (high [≥6·99] vs low [<6·99] C19-RS; hazard ratio [HR] 3·31 [95% CI 1·49-7·33], p=0·0033; and 2·58 [1·10-6·05], p=0·028), adjusted for clinical factors, biochemical biomarkers of inflammation and myocardial injury, and technical parameters. The adjusted HR for in-hospital mortality was 8·24 (95% CI 2·16-31·36, p=0·0019) in patients who received no dexamethasone treatment, but 2·27 (0·69-7·55, p=0·18) in those who received dexamethasone after the scan, suggesting that vascular inflammation might have been a therapeutic target of dexamethasone in COVID-19. Finally, C19-RS was strongly associated (r=0·61, p=0·00031) with a whole blood transcriptional module representing dysregulation of coagulation and platelet aggregation pathways. INTERPRETATION: Radiotranscriptomic analysis of CT angiography scans introduces a potentially powerful new platform for the development of non-invasive imaging biomarkers. Application of this platform in routine CT pulmonary angiography scans done in patients with COVID-19 produced the radiotranscriptomic signature C19-RS, a marker of cytokine-driven inflammation driving systemic activation of coagulation and responsible for adverse clinical outcomes, which predicts in-hospital mortality and might allow targeted therapy. FUNDING: Engineering and Physical Sciences Research Council, British Heart Foundation, Oxford BHF Centre of Research Excellence, Innovate UK, NIHR Oxford Biomedical Research Centre, Wellcome Trust, Onassis Foundation.
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COVID-19 , SARS-CoV-2 , Angiography , Artificial Intelligence , COVID-19/diagnostic imaging , Cytokines , Humans , Inflammation/diagnostic imaging , Prospective Studies , State Medicine , Tomography, X-Ray ComputedABSTRACT
PURPOSE: To determine how implementation of an artificial intelligence nodule algorithm, the Lung Cancer Prediction Convolutional Neural Network (LCP-CNN), at the point of incidental nodule detection would have influenced further investigation and management using a series of threshold scores at both the benign and malignant end of the spectrum. METHOD: An observational retrospective study was performed in the assessment of nodules between 5-15 mm (158 benign, 32 malignant) detected on CT scans, which were performed as part of routine practice. The LCP-CNN was applied to the baseline CT scan producing a percentage score, and subsequent imaging and management determined for each threshold group. We hypothesized that the 5% low risk threshold group requires only one follow-up, the 0.56% very low risk threshold group requires no follow-up and the 80% high risk threshold group warrants expedited intervention. RESULTS: The 158 benign nodules had an LCP-CNN score between 0.1 and 70.8%, median 5.5% (IQR 1.4-18.0), whilst the 32 cancer nodules had an LCP-CNN score between 10.1 and 98.7%, median 59.0% (IQR 37.1-83.9). 24/61 CT scans in the 0.56-5% group (n = 37) and 21/21 CT scans <0.56% group (n = 13) could be obviated resulting in an overall reduction of 18.6% (45/242) CT scans in the benign cohort. In the 80% group (n = 10), expedited intervention of malignant nodules could result in a 3.6-month reduction in time delay in 5 cancer patients. CONCLUSION: We show the potential of artificial intelligence to reduce the need for follow-up scans and intervention in low-scoring benign nodules, whilst potentially accelerating the investigation and treatment of high-scoring cancer nodules.
Subject(s)
Lung Neoplasms , Solitary Pulmonary Nodule , Artificial Intelligence , Humans , Lung Neoplasms/diagnostic imaging , Neural Networks, Computer , Retrospective Studies , Solitary Pulmonary Nodule/diagnostic imaging , Tomography, X-Ray ComputedABSTRACT
Colorectal liver metastases (CRLM) have heterogenous histopathological and immunohistochemical phenotypes, which are associated with variable responses to treatment and outcomes. However, this information is usually only available after resection, and therefore of limited value in treatment planning. Improved techniques for in vivo disease assessment, which can characterise the variable tumour biology, would support further personalization of management strategies. Advanced imaging of CRLM including multiparametric MRI and functional imaging techniques have the potential to provide clinically-actionable phenotypic characterisation. This includes assessment of the tumour-liver interface, internal tumour components and treatment response. Advanced analysis techniques, including radiomics and machine learning now have a growing role in assessment of imaging, providing high-dimensional imaging feature extraction which can be linked to clinical relevant tumour phenotypes, such as a the Consensus Molecular Subtypes (CMS). In this review, we outline how imaging techniques could reproducibly characterize the histopathological features of CRLM, with several matched imaging and histology examples to illustrate these features, and discuss the oncological relevance of these features. Finally, we discuss the future challenges and opportunities of CRLM imaging, with a focus on the potential value of advanced analytics including radiomics and artificial intelligence, to help inform future research in this rapidly moving field.
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INTRODUCTION: Deep Learning has been proposed as promising tool to classify malignant nodules. Our aim was to retrospectively validate our Lung Cancer Prediction Convolutional Neural Network (LCP-CNN), which was trained on US screening data, on an independent dataset of indeterminate nodules in an European multicentre trial, to rule out benign nodules maintaining a high lung cancer sensitivity. METHODS: The LCP-CNN has been trained to generate a malignancy score for each nodule using CT data from the U.S. National Lung Screening Trial (NLST), and validated on CT scans containing 2106 nodules (205 lung cancers) detected in patients from from the Early Lung Cancer Diagnosis Using Artificial Intelligence and Big Data (LUCINDA) study, recruited from three tertiary referral centers in the UK, Germany and Netherlands. We pre-defined a benign nodule rule-out test, to identify benign nodules whilst maintaining a high sensitivity, by calculating thresholds on the malignancy score that achieve at least 99 % sensitivity on the NLST data. Overall performance per validation site was evaluated using Area-Under-the-ROC-Curve analysis (AUC). RESULTS: The overall AUC across the European centers was 94.5 % (95 %CI 92.6-96.1). With a high sensitivity of 99.0 %, malignancy could be ruled out in 22.1 % of the nodules, enabling 18.5 % of the patients to avoid follow-up scans. The two false-negative results both represented small typical carcinoids. CONCLUSION: The LCP-CNN, trained on participants with lung nodules from the US NLST dataset, showed excellent performance on identification of benign lung nodules in a multi-center external dataset, ruling out malignancy with high accuracy in about one fifth of the patients with 5-15 mm nodules.
Subject(s)
Deep Learning , Lung Neoplasms , Solitary Pulmonary Nodule , Artificial Intelligence , Germany , Humans , Lung , Lung Neoplasms/diagnosis , Netherlands , Retrospective Studies , Solitary Pulmonary Nodule/diagnostic imagingABSTRACT
During the COVID-19 pandemic, chest CT is frequently used to help with the diagnosis. The classic CT patterns of COVID-19 pneumonia are well-published and recognised among radiologists. However, when there are pre-existing conditions particularly in the elderly population that could mask or result in similar patterns of disease, then the diagnosis is more difficult. This imaging essay highlights the commonly encountered situations including patients with heart failure, other possible infections particularly in the immunodeficient, and when there is trauma to the thorax. We illustrate imaging clues available to the radiologist to either make the diagnosis or at least reduce the differential diagnosis.
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OBJECTIVE: The chest radiograph (CXR) is the predominant imaging investigation being used to triage patients prior to either performing a SARS-CoV-2 polymerase chain reaction (PCR) test or a diagnostic CT scan, but there are limited studies that assess the diagnostic accuracy of CXRs in COVID-19.To determine the accuracy of CXR diagnosis of COVID-19 compared with PCR in patients presenting with a clinical suspicion of COVID-19. METHODS AND MATERIALS: The CXR reports of 569 consecutive patients with a clinical suspicion of COVID-19 were reviewed, blinded to the PCR result and classified into the following categories: normal, indeterminate for COVID-19, classic/probable COVID-19, non-COVID-19 pathology, and not specified. Severity reporting and reporter expertise were documented. The subset of this cohort that had CXR and PCR within 3 days of each other were included for further analysis for diagnostic accuracy. RESULTS: Classic/probable COVID-19 was reported in 29% (166/569) of the initial cohort. 67% (382/569) had PCR tests. 344 patients had CXR and PCR within 3 days of each other. Compared to PCR as the reference test, initial CXR had a 61% sensitivity and 76% specificity in the diagnosis of COVID-19. CONCLUSION: Initial CXR is useful as a triage tool with a sensitivity of 61% and specificity of 76% in the diagnosis of COVID-19 in a hospital setting. ADVANCES IN KNOWLEDGE: .Diagnostic accuracy does not differ significantly between specialist thoracic radiologists and general radiologists including trainees following training.There was a 40% prevalence of PCR positive disease in the cohort of patients (n = 344) having CXR and PCR within 3 days of each other.Classic/probable COVID-19 was reported in 29% of total cohort of patients presenting with clinical suspicion of COVID-19 (n = 569).Initial CXR is useful as a triage tool with a sensitivity of 61% and specificity of 76% in the diagnosis of COVID-19 in a hospital setting.
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Brown tumours do not represent neoplastic process, but they are focal bony lesions due to bone remodelling from either primary or secondary hyperparathyroidism. Their incidence is also low. The current literature on brown tumour is mainly in the form of case reports that focus on single affected sites. This pictorial review describes the full imaging workup and pathway of suspected brown tumour in the setting of both primary and secondary hyperparathyroidism. It aims to illustrate the management strategy to aid both clinicians and radiologists in suspected cases of brown tumour. We highlight the complementary roles that different imaging modalities can play in different settings including the importance of parathyroid ultrasound, 99mTc-sestamibi scintigraphy and SPECT/CT in the localisation of the parathyroid adenoma. We present cases with full clinical and imaging workup in both the acute and chronic setting and scenarios that require exclusion of primary and secondary bone malignancies.
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A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'Is microwave ablation (MWA) more effective than radiofrequency ablation (RFA) in achieving local control for primary lung cancer?'. Altogether, 439 papers were found, of which 7 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Both are thermal ablative techniques, with microwave ablation (MWA) the newer technique and radiofrequency ablation (RFA) with a longer track record. Lack of consensus with regard to definitions of technical success and efficacy and heterogeneity of study inclusions limits studies for both. The only direct comparison study does not demonstrate a difference with either technique in achieving local control. The quality of evidence for MWA is very limited by retrospective nature and heterogeneity in technique, power settings and tumour type. Tumour size and late-stage cancer were shown to be associated with higher rates of local recurrence in 1 MWA study. RFA studies were generally of a higher level of evidence comprising prospective trials, systematic review and meta-analysis. The recurrence rates for MWA and RFA overlapped, and for the included studies ranged between 16% and 44% for MWA and 9% and 58% for RFA. The current evidence, therefore, does not clearly demonstrate a benefit of MWA over RFA in achieving local control in primary lung cancer.
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A best evidence topic was written according to a structured protocol. The question addressed was: in patients with inoperable early-stage primary lung cancer does microwave ablation (MWA) or stereotactic ablative body radiotherapy (SBRT) achieve improved outcomes in terms of local control, recurrence, survival and complications? Altogether, more than 550 papers were found using the reported search, of which 12 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. No single study directly compared the effects of MWA with SBRT. However, the best available evidence for MWA (7 studies) was compared to that for SBRT (5 studies). The range of 3-year survival reported for MWA was 29.2-84.7%, compared with 42.7-63.5% for SBRT. The range of median survival was 35-60 months for MWA and 32.6-48 months for SBRT. This suggests similar outcomes between these two 2 techniques. Different side-effect profiles were observed between techniques with MWA associated with pneumothorax and fever and SBRT most commonly causing radiation pneumonitis and rib fractures. The evidence base for MWA is less than that for SBRT and is heterogenous in terms of participants and technical design. However, within these limitations, we conclude that MWA appears comparable with SBRT in terms of local control and survival rates.
Subject(s)
Ablation Techniques/methods , Carcinoma, Non-Small-Cell Lung/therapy , Lung Neoplasms/surgery , Microwaves/therapeutic use , Neoplasm Staging , Radiosurgery/methods , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/mortality , Global Health , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/mortality , Survival RateABSTRACT
OBJECTIVE: 18F-Fluciclovine (FACBC) is an amino acid PET radiotracer approved for recurrent prostate cancer imaging. We investigate the use of Bayesian penalised likelihood (BPL) reconstruction for 18F-fluciclovine PET. METHODS: 15 18F-fluciclovine scans were reconstructed using ordered subset expectation maximisation (OSEM), OSEM + point spread function (PSF) modelling and BPL using ß-values 100-600. Lesion maximum standardised uptake value (SUVmax), organ SUVmean and standard deviation were measured. Deidentified reconstructions (OSEM, PSF, BPL using ß200-600) from 10 cases were visually analysed by two readers who indicated their most and least preferred reconstructions, and scored overall image quality, noise level, background marrow image quality and lesion conspicuity. RESULTS: Comparing BPL to OSEM, there were significant increments in lesion SUVmax and signal-to-background up to ß400, with highest gain in ß100 reconstructions (mean ΔSUVmax 3.9, p < 0.0001). Organ noise levels increased on PSF, ß100 and ß200 reconstructions. Across BPL reconstructions, there was incremental reduction in organ noise with increasing ß, statistically significant beyond ß300-500 (organ-dependent). Comparing with OSEM and PSF, lesion signal-to-noise was significantly increased in BPL reconstructions where ß ≥ 300 and ≥ 200 respectively. On visual analysis, ß 300 had the first and second highest scores for image quality, ß500 and ß600 equal highest scores for marrow image quality and least noise, PSF and ß 200 had first and second highest scores for lesion conspicuity. For overall preference, one reader preferred ß 300 in 9/10 cases and the other preferred ß 200 in all cases. CONCLUSION: BPL reconstruction of 18F-fluciclovine PET images improves signal-to-noise ratio, affirmed by overall reader preferences. On balance, ß300 is suggested for 18F-fluciclovine whole body PET image reconstruction using BPL. Advances in knowledge: The optimum ß is different to that previously published for 18F-fluorodeoxyglucose, and has practical implications for a relatively new tracer in an environment with modern reconstruction technologies.
Subject(s)
Bayes Theorem , Carboxylic Acids , Cyclobutanes , Image Processing, Computer-Assisted/methods , Neoplasm Recurrence, Local/diagnostic imaging , Positron-Emission Tomography/methods , Prostatic Neoplasms/diagnostic imaging , Humans , Male , Prostate/diagnostic imaging , Prostate/pathology , Prostatic Neoplasms/pathology , Radiopharmaceuticals , Reproducibility of Results , Retrospective StudiesABSTRACT
INTRODUCTION: Lung cancer is a common cancer, with over 1.3 million cases worldwide each year. Early diagnosis using computed tomography (CT) screening has been shown to reduce mortality but also detect non-malignant nodules that require follow-up scanning or alternative methods of investigation. Practical and accurate tools that can predict the probability that a lung nodule is benign or malignant will help reduce costs and the risk of morbidity and mortality associated with lung cancer. METHODS: Retrospectively collected data from 1500 patients with pulmonary nodule(s) of up to 15 mm detected on routinely performed CT chest scans aged 18 years old or older from three academic centres in the UK will be used to to develop risk stratification models. Radiological, clinical and patient characteristics will be combined in multivariable logistic regression models to predict nodule malignancy. Data from over 1000 participants recruited in a prospective phase of the study will be used to evaluate model performance. Discrimination, calibration and clinical utility measures will be presented.
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A 66-year-old man presented with biochemical recurrence of prostate cancer and underwent F-fluciclovine PET/CT to detect sites of recurrence. He had a history of resected truncal stage IIIC malignant melanoma, with bilateral axillary node involvement on sentinel node biopsy, in complete remission for 3 years. F-fluciclovine PET/CT demonstrated an incidental fluciclovine-avid right axillary node (SUVmax = 4.3). Diagnostic sampling confirmed recurrent malignant melanoma.
Subject(s)
Carboxylic Acids , Cyclobutanes , Incidental Findings , Melanoma/diagnostic imaging , Melanoma/secondary , Positron Emission Tomography Computed Tomography , Prostatic Neoplasms/pathology , Humans , Male , Middle Aged , Recurrence , Sentinel Lymph Node BiopsyABSTRACT
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'in coronary artery bypass grafting using radial artery grafts, does proximal anastomosis to the aorta or left internal mammary artery achieve better patency'. Altogether >183 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Radial artery grafts typically have a narrower lumen than vein grafts, and as such there is some concern that anastomosing them directly to the aorta during coronary artery bypass grafting (CABG) may impair graft patency. As such, some surgeons prefer to anastomose radial artery grafts to a second-order vessel such as the left internal mammary artery (LIMA). We sought to assess the evidence for this. A handful of papers directly addressing the issue of the effect of the site of proximal anastomosis on graft patency were found, with three showing no significant difference. One such study reported an insignificant difference in angiographic patency at 32 months postoperatively, with 94.1% of off-aorta grafts remaining patent vs 87.2% of off-LIMA grafts (p = 0.123). However, a large-scale well-designed study was able to demonstrate a statistically significant difference at five years postoperatively, with 74.3% of off-aorta grafts patent, compared with 65.2% of off-LIMA (p = 0.004). Nonetheless, a number of papers that report patency for either off-aorta or off-LIMA grafts give comparable figures for each technique. Additionally, different centres and investigators report very different patency results for grafts that have the same site of proximal anastomosis. One centre was able to achieve patency rates for off-LIMA grafts of 88% up to a mean of 7.7 years postoperatively while another centre reported a patency rate of only 78.6% at three years. Given this, and the plethora of other factors influencing graft patency, we conclude that the best evidence suggests that the site of proximal anastomosis has little or no effect on radial artery graft patency following CABG.