Screening for Lung Cancer: CHEST guideline and expert panel report

Low-dose chest CT screening for lung cancer has become a standard of care in the United States, in large part because of the results of the National Lung Screening Trial (NLST). Additional evidence supporting the net benefit of low-dose chest CT screening for lung cancer, and increased experience in minimizing the potential harms, has accumulated since the prior iteration of these guidelines. Here, we update the evidence base for the benefit, harms, and implementation of low-dose chest CT screening. We use the updated evidence base to provide recommendations where the evidence allows, and statements based on experience and expert consensus where it does not. Approved panelists reviewed previously developed key questions using the Population, Intervention, Comparator, Outcome format to address the benefit and harms of low-dose CT screening, and key areas of program implementation. A systematic literature review was conducted using MEDLINE via PubMed, Embase, and the Cochrane Library on a quarterly basis since the time of the previous guideline publication. Reference lists from relevant retrievals were searched, and additional papers were added. Retrieved references were reviewed for relevance by two panel members. The quality of the evidence was assessed for each critical or important outcome of interest using the Grading of Recommendations, Assessment, Development and Evaluation approach. Meta-analyses were performed when enough evidence was available. Important clinical questions were addressed based on the evidence developed from the systematic literature review. Graded recommendations and ungraded statements were drafted, voted on, and revised until consensus was reached. The systematic literature review identified 75 additional studies that informed the response to the 12 key questions that were developed. Additional clinical questions were addressed resulting in seven graded recommendations and nine ungraded consensus statements. Evidence suggests that low-dose CT screening for lung cancer can result in a favorable balance of benefit and harms. The selection of screen-eligible individuals, the quality of imaging and image interpretation, the management of screen-detected findings, and the effectiveness of smoking cessation interventions can impact this balance.

Screening of Potential Cardiac Involvement in Competitive Athletes Recovering From COVID-19: An Expert Consensus Statement.

As our understanding of the complications of coronavirus disease-2019 (COVID-19) evolve, subclinical cardiac pathology such as myocarditis, pericarditis, and right ventricular dysfunction in the absence of significant clinical symptoms represents a concern. The potential implications of these findings in athletes are significant given the concern that exercise, during the acute phase of viral myocarditis, may exacerbate myocardial injury and precipitate malignant ventricular arrhythmias. Such concerns have led to the development and publication of expert consensus documents aimed at providing guidance for the evaluation of athletes after contracting COVID-19 in order to permit safe return to play. Cardiac imaging is at the center of these evaluations. This review seeks to evaluate the current evidence regarding COVID-19-associated cardiovascular disease and how multimodality imaging may be useful in the screening and clinical evaluation of athletes with suspected cardiovascular complications of infection. Guidance is provided with diagnostic "red flags" that raise the suspicion of pathology. Specific emphasis is placed on the unique challenges posed in distinguishing athletic cardiac remodeling from subclinical cardiac disease. The strengths and limitations of different imaging modalities are discussed and an approach to return to play decision making for athletes post-COVID-19, as informed by multimodality imaging, is provided.

Diagnostic accuracy of dopaminergic imaging in prodromal dementia with Lewy bodies.

BACKGROUND: Dopaminergic imaging has high diagnostic accuracy for dementia with Lewy bodies (DLB) at the dementia stage. We report the first investigation of dopaminergic imaging at the prodromal stage. METHODS: We recruited 75 patients over 60 with mild cognitive impairment (MCI), 33 with probable MCI with Lewy body disease (MCI-LB), 15 with possible MCI-LB and 27 with MCI with Alzheimer's disease. All underwent detailed clinical, neurological and neuropsychological assessments and FP-CIT [123I-N-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)] dopaminergic imaging. FP-CIT scans were blindly rated by a consensus panel and classified as normal or abnormal. RESULTS: The sensitivity of visually rated FP-CIT imaging to detect combined possible or probable MCI-LB was 54.2% [95% confidence interval (CI) 39.2-68.6], with a specificity of 89.0% (95% CI 70.8-97.6) and a likelihood ratio for MCI-LB of 4.9, indicating that FP-CIT may be a clinically important test in MCI where any characteristic symptoms of Lewy body (LB) disease are present. The sensitivity in probable MCI-LB was 61.0% (95% CI 42.5-77.4) and in possible MCI-LB was 40.0% (95% CI 16.4-67.7). CONCLUSIONS: Dopaminergic imaging had high specificity at the pre-dementia stage and gave a clinically important increase in diagnostic confidence and so should be considered in all patients with MCI who have any of the diagnostic symptoms of DLB. As expected, the sensitivity was lower in MCI-LB than in established DLB, although over 50% still had an abnormal scan. Accurate diagnosis of LB disease is important to enable early optimal treatment for LB symptoms.

An individualized strategy to estimate the effect of deformable registration uncertainty on accumulated dose in the upper abdomen.

In the abdomen, it is challenging to assess the accuracy of deformable image registration (DIR) for individual patients, due to the lack of clear anatomical landmarks, which can hamper clinical applications that require high accuracy DIR, such as adaptive radiotherapy. In this study, we propose and evaluate a methodology for estimating the impact of uncertainties in DIR on calculated accumulated dose in the upper abdomen, in order to aid decision making in adaptive treatment approaches. Sixteen liver metastasis patients treated with SBRT were evaluated. Each patient had one planning and three daily treatment CT-scans. Each daily CT scan was deformably registered 132 times to the planning CT-scan, using a wide range of parameter settings for the registration algorithm. A subset of 'realistic' registrations was then objectively selected based on distances between mapped and target contours. The underlying 3D transformations of these registrations were used to assess the corresponding uncertainties in voxel positions, and delivered dose, with a focus on accumulated maximum doses in the hollow OARs, i.e. esophagus, stomach, and duodenum. The number of realistic registrations varied from 5 to 109, depending on the patient, emphasizing the need for individualized registration parameters. Considering for all patients the realistic registrations, the 99th percentile of the voxel position uncertainties was 5.6 ± 3.3 mm. This translated into a variation (difference between 1st and 99th percentile) in accumulated D max in hollow OARs of up to 3.3 Gy. For one patient a violation of the accumulated stomach dose outside the uncertainty band was detected. The observed variation in accumulated doses in the OARs related to registration uncertainty, emphasizes the need to investigate the impact of this uncertainty for any DIR algorithm prior to clinical use for dose accumulation. The proposed method for assessing on an individual patient basis the impact of uncertainties in DIR on accumulated dose is in principle applicable for all DIR algorithms allowing variation in registration parameters.

Impact of the Publication of Appropriate Use Criteria on Utilization Rates of Myocardial Perfusion Imaging Studies in Ontario, Canada: A Population-Based Study.

BACKGROUND: Concern regarding overutilization of cardiac imaging has led to the development of appropriate use criteria (AUC). Myocardial perfusion imaging (MPI) is one of the most commonly used cardiac imaging modalities worldwide. Despite multiple iterations of AUC, there is currently no evidence regarding their real-world impact on population-based utilization rates of MPI. Our goal was to assess the impact of the AUC on rates of MPI in Ontario, Canada. We hypothesized that publication of the AUC would be associated with a significant reduction in MPI rates. METHODS AND RESULTS: We conducted a retrospective cohort study of the adult population of Ontario from January 1, 2000, to December 31, 2015. Age- and sex-standardized rates were compared from 4 different periods intersected by 3 published iterations of the AUC. Overall, 3 072 611 MPI scans were performed in Ontario during our study period. The mean monthly rate increased from 14.1/10 000 in the period from January 2000 to October 2005 to 18.2/10 000 between November 2005 and June 2009. After this point in time, there was a reduction in rates, falling to a mean monthly rate of 17.1/10 000 between March 2014 and December 2015. Time series analysis revealed that publication of the 2009 AUC was associated with a significant reduction in MPI rates (P<0.001). This translated into ≈88 849 fewer MPI scans at a cost savings of ≈72 million Canadian dollars. CONCLUSIONS: Our results reflect a potential real-world impact of the 2009 MPI AUC by demonstrating evidence of a significant effect on population-based rates of MPI.

PREDICTION OF RELAPSE FROM HYPERTHYROIDISM FOLLOWING ANTITHYROID MEDICATION WITHDRAWAL USING TECHNETIUM THYROID UPTAKE SCANNING.

OBJECTIVE: Technetium thyroid uptake (TTU) is not inhibited by antithyroid drugs (ATD) and reflects the degree of thyroid stimulation. We intended to predict the relapse rate from hyperthyroidism based on TTU measurement. METHODS: Out of 44 initially enrolled subjects, 38 patients aged 41.6 ± 14.6 with Graves disease (duration: 84 ± 78 months) completed the study. TTU was performed with 40-second imaging of the neck and mediastinum 20 minutes after injection of 1 mCi technetium-99m pertechnetate. TTU was measured as the percentage of the count of activity accumulated in the thyroidal region minus the mediastinal background uptake to the count of 1 mCi technetium-99m under the same acquisition conditions. Then methimazole was stopped and patients were followed. The optimal TTU cutoff value for Graves relapse prediction was calculated using Youden's J statistic. RESULTS: Hyperthyroidism relapsed in 11 (28.9%) patients 122 ± 96 (range: 15-290) days post-ATD withdrawal. The subjects in remission were followed for 209 ± 81 days (range: 88-390). TTU was significantly higher in patients with forthcoming relapse (12.0 ± 8.0 vs. 3.9 ± 2.0, P = .007). The difference was significant after adjustment for age, sex, history of previous relapse, disease duration, and thyroid-stimulating hormone (TSH) levels before withdrawal. The area under the receiver operative characteristic (ROC) curve was 0.87. The optimal TTU cutoff value for classification of subjects with relapse and remission was 8.7 with sensitivity, specificity, and positive and negative predictive value of 73%, 100%, 100%, and 90%, respectively (odds ratio [OR] = 10.0; 95% confidence interval [CI]: 3.4-29.3). CONCLUSION: TTU evaluation in hyperthyroid patients receiving antithyroid medication is an accurate and practical method for predicting relapse after ATD withdrawal. ABBREVIATIONS: ATD = antithyroid drugs RIU = radio-iodine uptake TSH = thyroid-stimulating hormone TSI = thyroid-stimulating immunoglobulin TTU = technetium thyroid uptake.

Opportunities for improvement on current nuclear cardiology practices and radiation exposure in Latin America: Findings from the 65-country IAEA Nuclear Cardiology Protocols cross-sectional Study (INCAPS).

BACKGROUND: Comparison of Latin American (LA) nuclear cardiology (NC) practice with that in the rest of the world (RoW) will identify areas for improvement and lead to educational activities to reduce radiation exposure from NC. METHODS AND RESULTS: INCAPS collected data on all SPECT and PET procedures performed during a single week in March-April 2013 in 36 laboratories in 10 LA countries (n = 1139), and 272 laboratories in 55 countries in RoW (n = 6772). Eight "best practices" were identified a priori and a radiation-related Quality Index (QI) was devised indicating the number used. Mean radiation effective dose (ED) in LA was higher than in RoW (11.8 vs 9.1 mSv, p < 0.001). Within a populous country like Brazil, a wide variation in laboratory mean ED was found, ranging from 8.4 to 17.8 mSv. Only 11% of LA laboratories achieved median ED <9 mSv, compared to 32% in RoW (p < 0.001). QIs ranged from 2 in a laboratory in Mexico to 7 in a laboratory in Cuba. Three major opportunities to reduce ED for LA patients were identified: (1) more laboratories could implement stress-only imaging, (2) camera-based methods of ED reduction, including prone imaging, could be more frequently used, and (3) injected activity of 99mTc could be adjusted reflecting patient weight/habitus. CONCLUSIONS: On average, radiation dose from NC is higher in LA compared to RoW, with median laboratory ED <9 mSv achieved only one third as frequently as in RoW. Opportunities to reduce radiation exposure in LA have been identified and guideline-based recommendations made to optimize protocols and adhere to the "as low as reasonably achievable" (ALARA) principle.

Administered Activities in Pediatric Nuclear Medicine and the Impact of the 2010 North American Consensus Guidelines on General Hospitals in the United States.

UNLABELLED: We sought to describe the practice of pediatric nuclear medicine at general hospitals in the United States and to assess the impact of dose awareness campaigns such as Image Gently. METHODS: A web-based survey was developed that requested information regarding hospital type, whether the hospital practices pediatric nuclear medicine, and the hospital's method for determining the administered activity for children. The survey invitation was emailed to a sample of general hospitals with more than 300 beds, excluding dedicated pediatric, veterans, psychiatric, and rehabilitation hospitals. Data were collected for 5 procedures performed on children: (99m)Tc-methylene diphosphate (MDP) bone scans, (99m)Tc-mercaptoacetyltriglycine (MAG3) renograms, (99m)Tc-dimercaptosuccinic acid (DMSA) renal cortical scans, (99m)Tc-based hepatobiliary scans, and (18)F-FDG PET scans. The sites reported dosage by weight (MBq/kg), minimum and maximum dosages, and the activities that they would administer to 2 hypothetical patients: a 5-y-old boy (20 kg, 110 cm tall) and a 10-y-old girl (30 kg, 140 cm tall). RESULTS: The invitation was delivered to 196 sites, with 121 (61.7%) responding. Eighty-two hospitals (67.8%) performed nuclear medicine on children. All sites scaled administered activity for children, mostly by body weight. Also, 82.4% of sites indicated they were familiar with Image Gently, 57.1% were familiar with the 2010 North American consensus guidelines for children, and 54.9% altered their protocols because of the guidelines. The median value for parameters defined by the guidelines was equal to the guideline-recommended value for all procedures. More than 50% of the sites-particularly those familiar with the guidelines-were compliant with the guidelines regarding both the acquisition parameters and the administered activities for the 2 hypothetical patients. However, there remained a wide variation in practice, sometimes by more than a factor of 10, for sites not familiar with the guidelines. CONCLUSION: Image Gently and the North American guidelines have had a substantial impact on pediatric nuclear medicine practice in the United States. However, a wide variation in practice still exists, particularly for sites not familiar with the guidelines. Further promotion and dissemination of the guidelines and best practice are still necessary.

¿Están indicadas las pruebas de imagen urgentes en el manejo de la pancreatitis aguda? / Are urgent imaging tests indicated in the management of acute pancreatitis?

La pancreatitis aguda es una urgencia frecuente dentro de la patología abdominal. Se acepta que para su diagnóstico se requieren dos de tres condiciones: presentación clínica típica, datos característicos analíticos y/o en pruebas de imagen. Probablemente, por razones de eficiencia y frecuencia, los dos primeros puntos son los más habitualmente usados. Sin embargo, la necesidad de estudios radiológicos es en ocasiones una fuente de conflicto. Por ello, decidimos realizar una revisión de la evidencia actual en cuanto a la indicación de realización de pruebas de imagen de forma urgente para el manejo de la pancreatitis aguda (AU)

Acute pancreatitis is a common emergency within abdominal disease. It is accepted that two of three conditions must be fulfilled for its diagnosis: characteristic clinical presentation, characteristic laboratory findings, and/or characteristic diagnostic imaging findings. The first two conditions are the most often used, probably for reasons of efficiency and frequency. Nevertheless, the need for imaging studies is sometimes a source of conflict. For this reason, we decided to review the current evidence regarding the indication of urgent imaging tests in the management of acute pancreatitis (AU)

Patient doses from CT examinations in Turkey.

PURPOSE: We aimed to establish the first diagnostic reference levels (DRLs) for computed tomography (CT) examinations in adult and pediatric patients in Turkey and compare these with international DRLs. METHODS: CT performance information and examination parameters (for head, chest, high-resolution CT of the chest [HRCT-chest], abdominal, and pelvic protocols) from 1607 hospitals were collected via a survey. Dose length products and effective doses for standard patient sizes were calculated from the reported volume CT dose index (CTDIvol). RESULTS: The median number of protocols reported from the 167 responding hospitals (10% response rate) was 102 across five different age groups. Third quartile CTDIvol values for adult pelvic and all pediatric body protocols were higher than the European Commission standards but were comparable to studies conducted in other countries. CONCLUSION: The radiation dose indicators for adult patients were similar to those reported in the literature, except for those associated with head protocols. CT protocol optimization is necessary for adult head and pediatric chest, HRCT-chest, abdominal, and pelvic protocols. The findings from this study are recommended for use as national DRLs in Turkey.

Current status of nuclear cardiology in Japan: Ongoing efforts to improve clinical standards and to establish evidence.

Nuclear cardiology imaging tests are widely performed in Japan as clinical practice. The Japanese nuclear cardiology community has developed new diagnostic imaging tests using (123)I-beta-methyl-p-iodophenyl-pentadecanoic acid, (123)I-metaiodobenzylguanidine, and (18)F-fluorodeoxyglucose PET for detecting cardiac involvement in sarcoidosis. These tests have become popular worldwide. The Japanese Circulation Society and the Japanese Society of Nuclear Cardiology have published clinical imaging guidelines showing indications and standards for the new imaging tests. JSNC is currently striving to improve the standard of clinical practice and is promoting research activities.

Russian practical guidance on radiological support for justification of X-ray and nuclear medicine examinations.

An important part of the justification process is assessment of the radiation risks caused by exposure of a patient during examination. The authors developed official national methodology both for medical doctors and sanitary inspectors called 'assessment of radiation risks of patients undergoing diagnostic examinations with the use of ionizing radiation'. The document addresses patients of various age groups and a wide spectrum of modern X-ray and nuclear medicine examinations. International scale of risk categorisation was implemented by the use of effective dose with account for age dependence of radiation risk. The survey of effective doses in radiology, including CT, mammography, and intervention radiology, and nuclear medicine, including single-photon emission tomography and positron emission tomography, for patients of various age groups from several regions of Russia was used for the risk assessment. The output of the methodology is a series of tables for each diagnostic technology with lists of examinations for three age groups (children/adolescents, adults and seniors) corresponding to various radiation risk categories.

Angiosarcoma epitelioide óseo multifocal con metástasis pulmonares / Multifocal epithelioid angiosarcoma of bone with lung metastases

Los angiosarcomas son neoplasias mesenquimales poco frecuentes que pueden derivar de tejido vascular o linfático. Los angiosarcomas óseos son extremadamente infrecuentes, representando menos del 1% de todos los angiosarcomas. Se trata de tumores muy agresivos, con metástasis en el diagnóstico inicial en un gran porcentaje de casos. Radiológicamente suelen aparecer como lesiones líticas muy agresivas, con frecuente extensión a partes blandas, que en tomografía computarizada o en resonancia magnética suelen estar hipervascularizadas. El aspecto en la gammagrafía ósea es variable, con hipercaptación o hipocaptación del trazador. Predominan en los huesos largos pero en un 10% pueden localizarse en las vértebras. En un 20-50% de los casos son multicéntricos. Existen pocos casos descritos en la bibliografía de angiosarcoma óseo con metástasis pulmonares. Presentamos el caso de un paciente con un angiosarcoma epitelioide multifocal (vertebral y costal), con metástasis pulmonares demostradas en la tomografía computarizada torácica y en la gammagrafía ósea convencional (AU)

Angiosarcoma is a rare mesenchymal neoplasm that may arise from vascular or lymphatic tissue. Bone primary angiosarcoma is extremely rare, representing less than 1% of all angiosarcomas. It́s a very aggressive neoplasm and patients have metastatic disease at initial diagnosis in a large percentage of cases. On radiographs, these lesions are usually aggressive osteolytic lesions, commonly with soft-tissue mass extension, and tumoral enhancement on CT or MR imaging. The appearance of the bone scan is variable, describing studies with tracer uptake or low uptake. These tumours are more often found in the long bones, but spinal involvement has been reported in 10% of patients. There are a few reports in the literature of bone angiosarcoma with lung metastases. We present a patient with multifocal epithelioid angiosarcoma (spine and ribs) and multiple lung metastasis, evidenced by CT and conventional bone scintigraphy, with a fast growth (AU)

Tirotoxicosis en paciente con enfermedad trofoblástica gestacional. A propósito de un caso / Hyperthyroidism in metastatic gestational trophoblastic disease. A case report

La gonadotropina coriónica humana (hCG) es producida por el trofoblasto tanto en el embarazo como en la enfermedad trofoblástica gestacional (ETG). La subunidad α de la hCG es idéntica a las subunidades α de otras hormonas, como hormona luteinizante (LH), la hormona folículo estimulante (FSH) y la hormona estimulante de la tiroides (TSH). Una elevación marcada de hCG se asocia a la presencia de complicaciones como la hiperémesis gravídica, el desarrollo precoz de preeclampsia y, ocasionalmente, con el hipertiroidismo. Los procedimientos de laboratorio utilizados para la medición de los niveles de hCG son bastante sensibles y específicos para el estudio de las condiciones del trofoblasto (AU)

Human chorionic gonadotropin (hCG) is produced by trophoblasts in pregnancy as well as in gestational trophoblastic diseases (GTD). The alpha subunit is identical to that for luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH). Elevated serum levels of hCG can lead to complications that include hyperemesis gravidarum, early development of preeclampsia, and occasionally hyperthyroidism. Laboratory test for hCG are very sensitive and specific (AU)

A gluten-free vegan meal for gastric emptying scintigraphy: establishment of reference values and its utilization in the evaluation of diabetic gastroparesis.

PURPOSE: The aim of this study was to describe the preparation of radiolabeled idli (savory cake) meal for use as an alternate to the egg white sandwich (EWS) meal in gastric emptying scintigraphy (GES). Furthermore, the aim of this study was to establish normal emptying rates for this meal and present our experience in using it in the evaluation of diabetic gastroparesis. PATIENTS AND METHODS: The meal was prepared using a universally available packaged mix labeled with 1 mCi 99mTc sulfur colloid, and the stability of labeling was tested up to 4 hours in simulated gastric fluid. One hundred thirteen healthy volunteers (aged 20-78 years; 54 women, 59 men) underwent GES study using the idli meal. Gastric retention at one-half, 1, 2, and 4 hours after ingestion of the meal was estimated, and the normal limits were set using the fifth and 95th percentile values at each period. Having established its normal emptying rates, the idli meal was further used to evaluate 70 patients suspected with diabetic gastroparesis. RESULTS: The idli meal, with a calorific value ≈282 kcal, has a relatively higher fat content (8% of total mass) than EWS. More than 96% of 99mTc sulfur colloid remained bound to the meal after 4 hours suspension in simulated gastric fluid. Gastric retention greater than 30% and greater than 6% at 2 hours and 4 hours, respectively, indicated delayed gastric emptying, whereas retention less than 30% at 1 hour suggested rapid emptying. Among patients suspected with diabetic gastroparesis, delayed gastric emptying was identified in 76%, and rapid emptying was seen in 4.2%. CONCLUSIONS: Radiolabeled idli meal is a good alternative to EWS meal for routine GES, especially among patients with specific dietary restrictions.

The importance of a supportive environment in clinical audit: a pilot study of doctors' engagement with the NHS National PET-CT audit programme.

PURPOSE: The NHS National PET-CT Audit Programme was launched in 2008 as part of a national NHS programme to widen patient access to PET-computed tomography (CT) imaging in England. However, to implement clinical audit effectively, healthcare professionals need to be fully engaged with the process. The purpose of the pilot study was to identify and explore the different factors that influence doctors' engagement with the National NHS PET-CT Audit Programme. METHODS: A single embedded case study was undertaken, which centred on the NHS National PET-CT Audit Programme. Seven theoretical propositions drawn from a review of the literature were tested and their influence evaluated. A purposeful sample of 13 semistructured interviews with consultant doctors was taken from different hospitals over a 6-month period. The data were analysed using directed thematic content analysis, with the themes compared against the study's propositions. RESULTS: Doctors' perspectives of clinical audit changed in response to the way in which the audit was implemented. The main barriers to engagement were the lack of a common vision and poor communication, which contributed to poor interprofessional relationships and a perceived culture of blame. In contrast, factors that facilitated engagement centred on the adoption of a more supportive and collaborative approach, which in turn facilitated higher levels of trust between professionals. The dissemination of performance data was found to be a key influencing factor. CONCLUSION: The study makes use of a unique data set and to the best of our knowledge is one of the first studies to document how the dissemination of doctors' performance data positively influences engagement with clinical audit in England. In addition, the study also shows how, contrary to some studies in the literature, clinical audit can reduce professional anxiety by providing a validation of professional competence. The study supports the premise that clinical audit will be fully embraced by doctors only if they are sufficiently involved in the process so as to be able to redefine and clarify its purpose and meaning. The preliminary findings of this pilot study provide the theoretical underpinning for a national survey into reporter perspectives of the National PET-CT Audit Programme.