RadioGraphics Update: The 10 Pillars of Lung Cancer Screening-Rationale and Logistics of a Lung Cancer Screening Program.

Editor's Note.-RadioGraphics Update articles supplement or update information found in full-length articles previously published in RadioGraphics. These updates, written by at least one author of the previous article, provide a brief synopsis that emphasizes important new information such as technological advances, revised imaging protocols, new clinical guidelines involving imaging, or updated classification schemes.

Impact of Baseline Interstitial Lung Abnormalities on Pneumonitis Risk in Patients Receiving Immune Checkpoint Inhibitors for Non-Small-Cell Lung Cancer.

INTRODUCTION/BACKGROUND: Immune-related pneumonitis is a potentially fatal complication of treatment with immune checkpoint inhibitors (ICIs). Interstitial lung disease (ILD) is associated with increased risk for pneumonitis, but the impact of interstitial abnormalities (ILA) in the absence of ILD has not been extensively assessed. We examined the relationship between ILA on pretreatment chest computed tomography (CT) scans and risk of pneumonitis in patients with non-small-cell lung cancer (NSCLC). METHODS: This retrospective cohort study included consecutive adult patients who received ICI for NSCLC between January 2013 and January 2020 at our institution. Two thoracic radiologists blinded to clinical outcomes independently reviewed pre-ICI chest CTs to identify and categorize ILA using previously published definitions. We used uni- and multivariable analysis adjusted for age, radiation, and smoking status to assess for associations between ILA, clinicopathologic characteristics, and symptomatic (CTCAE grade ≥2) pneumonitis. RESULTS: Of 475 patients who received ICI treatment and met inclusion criteria, baseline ILA were present in 78 (16.4%) patients, most commonly as a subpleural nonfibrotic pattern. In total, 43 (9.1%) of 475 patients developed symptomatic pneumonitis. Pneumonitis occurred in 16.7% of patients with ILA compared to 7.6% patients without ILA (P < .05). Presence of ground glass and extent of lung parenchymal involvement were associated with an increased risk of pneumonitis. On multivariable analysis, baseline ILA remained associated with increased risk of symptomatic pneumonitis (OR 2.2, 95% CI, 1.0-4.5). CONCLUSIONS: Baseline ILAs are associated with the development of symptomatic pneumonitis in patients with NSCLC treated with ICI. Additional studies are needed to validate these observations.

ACR Appropriateness Criteria® Routine Chest Imaging.

Routine chest imaging has been used to identify unknown or subclinical cardiothoracic abnormalities in the absence of symptoms. Various imaging modalities have been suggested for routine chest imaging. We review the evidence for or against the use of routine chest imaging in different clinical scenarios. This document aims to determine guidelines for the use of routine chest imaging as initial imaging for hospital admission, initial imaging prior to noncardiothoracic surgery, and surveillance imaging for chronic cardiopulmonary disease. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

U.S. Newspaper Coverage of Lung Cancer Screening From 2010 to 2022.

BACKGROUND. Newspapers are an important source of information for the public about low-dose CT (LDCT) lung cancer screening (LCS) and may influence public perception and knowledge of this important cancer screening service. OBJECTIVE. The purpose of this article was to evaluate the volume, content, and other characteristics of articles pertaining to LCS that have been published in U.S. newspapers. METHODS. The ProQuest U.S. Newsstream database was searched for U.S. newspaper articles referring to LCS published between January 1, 2010 (the year of publication of the National Lung Screening Trial results), and March 28, 2022. Search terms included "lung cancer screening(s)," "lung screening(s)," "low dose screening(s)," and "LDCT." Search results were reviewed to identify those articles mentioning LCS. Characteristics of included articles and originating newspapers were extracted. Articles were divided among nine readers, who independently assessed article sentiment regarding LCS and additional article content using a standardized form. RESULTS. The final analysis included 859 articles, comprising 816 nonsyndicated articles published in a single newspaper and 43 syndicated articles published in multiple newspapers. Sentiment regarding LCS was positive in 76% (651/859) of articles, neutral in 21% (184/859), and negative in 3% (24/859). Frequency of positive sentiment was lowest (61%) for articles published from 2010 to 2012; frequency of negative sentiment was highest (8%) for articles published in newspapers in the highest quartile for weekly circulation. LCS enrollment criteria were mentioned in 52% of articles, smoking cessation programs in 28%, need for annual CT in 27%, and shared decision-making in 4%. Cost or insurance coverage for LCS was mentioned in 33% in articles. A total of 64% of articles mentioned at least one benefit of LCS (most commonly early detection or possible cure of lung cancer), and 23% mentioned at least one harm (most commonly false-positives). A total of 9% of articles interviewed or mentioned a radiologist. CONCLUSION. The sentiment of U.S. newspaper articles covering LCS from 2010 to 2022 was overall positive. However, certain key elements of LCS were infrequently mentioned. CLINICAL IMPACT. The findings highlight areas for potential improvement of LCS media coverage; radiologists have an opportunity to take a more active role in this coverage.

Vasculopathy and Increased Vascular Congestion in Fatal COVID-19 and Acute Respiratory Distress Syndrome.

Rationale: The leading cause of death in coronavirus disease 2019 (COVID-19) is severe pneumonia, with many patients developing acute respiratory distress syndrome (ARDS) and diffuse alveolar damage (DAD). Whether DAD in fatal COVID-19 is distinct from other causes of DAD remains unknown. Objective: To compare lung parenchymal and vascular alterations between patients with fatal COVID-19 pneumonia and other DAD-causing etiologies using a multidimensional approach. Methods: This autopsy cohort consisted of consecutive patients with COVID-19 pneumonia (n = 20) and with respiratory failure and histologic DAD (n = 21; non-COVID-19 viral and nonviral etiologies). Premortem chest computed tomography (CT) scans were evaluated for vascular changes. Postmortem lung tissues were compared using histopathological and computational analyses. Machine-learning-derived morphometric analysis of the microvasculature was performed, with a random forest classifier quantifying vascular congestion (CVasc) in different microscopic compartments. Respiratory mechanics and gas-exchange parameters were evaluated longitudinally in patients with ARDS. Measurements and Main Results: In premortem CT, patients with COVID-19 showed more dilated vasculature when all lung segments were evaluated (P = 0.001) compared with controls with DAD. Histopathology revealed vasculopathic changes, including hemangiomatosis-like changes (P = 0.043), thromboemboli (P = 0.0038), pulmonary infarcts (P = 0.047), and perivascular inflammation (P < 0.001). Generalized estimating equations revealed significant regional differences in the lung microarchitecture among all DAD-causing entities. COVID-19 showed a larger overall CVasc range (P = 0.002). Alveolar-septal congestion was associated with a significantly shorter time to death from symptom onset (P = 0.03), length of hospital stay (P = 0.02), and increased ventilatory ratio [an estimate for pulmonary dead space fraction (Vd); p = 0.043] in all cases of ARDS. Conclusions: Severe COVID-19 pneumonia is characterized by significant vasculopathy and aberrant alveolar-septal congestion. Our findings also highlight the role that vascular alterations may play in Vd and clinical outcomes in ARDS in general.

United States lung cancer screening program websites: radiology representation, multimedia and multilingual content.

PURPOSE: To assess radiology representation, multimedia content, and multilingual content of United States lung cancer screening (LCS) program websites. MATERIALS AND METHODS: We identified the websites of US LCS programs with the Google internet search engine using the search terms lung cancer screening, low-dose CT screening, and lung screening. We used a standardized checklist to assess and collect specific content, including information regarding LCS staff composition and references to radiologists and radiology. We also tabulated types and frequencies of included multimedia and multilingual content and patient narratives. RESULTS: We analyzed 257 unique websites. Of these, only 48% (124 of 257) referred to radiologists or radiology in text, images, or videos. Radiologists were featured in images or videos on only 14% (36 of 257) of websites. Radiologists were most frequently acknowledged for their roles in reading or interpreting imaging studies (35% [90 of 574]). Regarding multimedia content, only 36% (92 of 257) of websites had 1 image, 27% (70 of 257) included 2 or more images, and 26% (68 of 257) of websites included one or more videos. Only 3% (7 of 257) of websites included information in a language other than English. Patient narratives were found on only 15% (39 of 257) of websites. CONCLUSIONS: The field of Radiology is mentioned in text, images, or videos by less than half of LCS program websites. Most websites make only minimal use of multimedia content such as images, videos, and patient narratives. Few websites provide LCS information in languages other than English, potentially limiting accessibility to diverse populations.

Community and Hospital Acquired Pneumonia.

Community-acquired pneumonia is the most common cause of death among infectious diseases, and responsible for millions of hospitalizations annually. Pneumonia may be classified based on how it is acquired, etiology, and clinical presentation. Chest radiographs are the gold standard for initial imaging evaluation and chest computed tomography plays an important role in diagnostic problem-solving and evaluation of complicated and treatment-resistant pneumonia. Follow-up imaging with chest radiographs or computed tomography post-illness resolution may be used to identify treatment-resistant inflammation or unidentified underlying malignancies.

Assessing Public Interest in Elective Surgery During the COVID-19 Pandemic: A Google Trends Analysis.

Objective: To determine trends in internet search volume for elective surgery terms during the first peak of the coronavirus disease 2019 (COVID-19) pandemic using Google Trends data. Background: Postponement of much-needed elective and urgent oncologic surgeries takes a toll on patients and the health care system. The COVID-19 pandemic has led to a decline in elective surgery volume, partially due to the cancellation of elective surgeries at the start of the pandemic. Methods: We performed a cross-sectional analysis of internet search volume trends for elective surgery terms during the first peak of the COVID-19 pandemic using Google Trends data and compared to a control group of terms representing common urgent and oncologic surgeries. Results: Search volume for elective surgery terms ("knee replacement," "spinal fusion," "hip replacement," "laminectomy," "cataract surgery") revealed a decrease of up to 54% compared to the prepandemic period, a significantly greater decrease than search volume for urgent and oncologic surgery terms ("C-section," "cholecystectomy," "CABG," "colectomy," "lobectomy," and "mastectomy"). Conclusions: The first phase of the COVID-19 pandemic led to sharp declines in search volume for essential elective surgical procedures, which may have been partially due to the cancellation of elective surgeries, but patient factors such as a temporary decline in interest in elective surgery might have also played a role. Attention to internet search volume may be used during future public health crises to monitor public engagement and interest in important health topics, including preventive health measures such as cancer screening.

Racial and Ethnic Disparities in Lung Cancer Screening Eligibility.

Background To address disparities in lung cancer screening (LCS) that may exclude large numbers of high-risk African American smokers, revised U.S. Preventive Services Task Force (USPSTF) recommendations lowered LCS eligibility thresholds. However, there are limited recent data about the impact of newly revised guidelines on disparities in LCS eligibility. Purpose To evaluate the impact of revised USPSTF guidelines on racial and ethnic disparities in LCS eligibility. Materials and Methods Cross-sectional survey data from 20 states were retrospectively evaluated from the 2019 Behavioral Risk Factor Surveillance System survey (median response rate, 49.4%). Respondents without a history of lung cancer aged 55-79 years (ie, under the previous guidelines) or aged 50-79 years (ie, under the revised guidelines) were included. Multivariable logistic regression analyses were performed to evaluate the association between race and ethnicity and LCS eligibility. All analyses were performed accounting for complex survey design features (ie, weighting, stratification, and clustering). Results Under previous guidelines, 11% of 67 567 weighted survey respondents were eligible for LCS (White [12%], Hispanic [4%], African American [7%], American Indian [17%], Asian or Pacific Islander [4%], and other [12%]). Under revised USPSTF guidelines, 14% of 77 689 weighted survey respondents were eligible for LCS (White [15%], Hispanic [5%], African American [9%], American Indian [21%), Asian or Pacific Islander [5%], and other [18%]). Compared with White respondents, African American respondents (adjusted odds ratio [OR] = 0.36; 95% CI: 0.27, 0.47; P < .001) and Hispanic respondents (adjusted OR = 0.15; 95% CI: 0.09, 0.24; P < .001) were less likely to be eligible for LCS under previous guidelines. African American respondents (adjusted OR = 0.39; 95% CI: 0.32, 0.47; P < .001) and Hispanic respondents (adjusted OR = 0.15; 95% CI: 0.10, 0.23; P < .001) were less likely to be eligible under the revised guidelines. The Wald test showed no evidence of differences in the degree to which racial and ethnic minority groups were less likely to be eligible for LCS when comparing previous versus revised USPSTF guidelines (P = .76). Conclusion The revised U.S. Preventive Services Task Force guidelines (version 2.0) may perpetuate lung cancer disparities, as racial and ethnic minority groups are still less likely to be eligible for lung cancer screening. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Jacobs and Springfield in this issue.

Imaging Manifestations of Chest Trauma.

Trauma is the leading cause of death among individuals under 40 years of age, and pulmonary trauma is common in high-impact injuries. Unlike most other organs, the lung is elastic and distensible, with a physiologic capacity to withstand significant changes in contour and volume. The most common types of lung parenchymal injury are contusions, lacerations, and hematomas, each having characteristic imaging appearances. A less common type of lung injury is herniation. Chest radiography is often the first-line imaging modality performed in the assessment of the acutely injured patient, although there are inherent limitations in the use of this modality in trauma. CT images are more accurate for the assessment of the nature and extent of pulmonary injury than the single-view anteroposterior chest radiograph that is typically obtained in the trauma bay. However, the primary limitations of CT concern the need to transport the patient to the CT scanner and a longer processing time. The American Association for the Surgery of Trauma has established the most widely used grading scale to describe lung injury, which serves to communicate severity, guide management, and provide useful prognostic factors in a systematic fashion. The authors provide an in-depth exploration of the most common types of pulmonary parenchymal, pleural, and airway injuries. Injury grading, patient management, and potential complications of pulmonary injury are also discussed. ©RSNA, 2021.

Practical application and validation of the 2018 ATS/ERS/JRS/ALAT and Fleischner Society guidelines for the diagnosis of idiopathic pulmonary fibrosis.

BACKGROUND: Accurate diagnosis of idiopathic pulmonary fibrosis (IPF) is essential to inform prognosis and treatment. In 2018, the ATS/ERS/JRS/ALAT and Fleischner Society released new diagnostic guidelines for usual interstitial pneumonitis (UIP)/IPF, adding Probable UIP as a CT category based on prior studies demonstrating this category had relatively high positive predictive value (PPV) for histopathologic UIP/Probable UIP. This study applies the 2018 ATS/ERS/JRS/ALAT and Fleischner Society guidelines to determine test characteristics of CT categories in academic clinical practice. METHODS: CT and histopathology were evaluated by three thoracic radiologists and two thoracic pathologists. Comparison of consensus categorization by the 2018 ATS and Fleischner Society guidelines by CT and histopathology was performed. RESULTS: Of patients with CT UIP, 87% (PPV, 95% CI: 60-98%) had histopathologic UIP with 97% (CI: 90-100%) specificity. Of patients with CT Probable UIP, 38% (PPV, CI: 14-68%) had histopathologic UIP and 46% (PPV, CI: 19-75%) had either histopathologic UIP or Probable UIP, with 88% (CI: 77-95%) specificity. Patients with CT Indeterminate and Alternative Diagnosis had histopathologic UIP in 27% (PPV, CI: 6-61%) and 21% (PPV, CI: 11-33%) of cases with specificities of 90% (CI: 80-96%) and 25% (CI: 16-37%). Interobserver variability (kappa) between radiologists ranged 0.32-0.81. CONCLUSIONS: CT UIP and Probable UIP have high specificity for histopathologic UIP, and CT UIP has high PPV for histopathologic UIP. PPV of CT Probable UIP was 46% for combined histopathologic UIP/Probable UIP. Our results indicate that additional studies are needed to further assess and refine the guideline criteria to improve classification performance.

Artificial intelligence-based vessel suppression for detection of sub-solid nodules in lung cancer screening computed tomography.

BACKGROUND: Lung cancer screening (LCS) with low-dose computed tomography (LDCT) helps early lung cancer detection, commonly presenting as small pulmonary nodules. Artificial intelligence (AI)-based vessel suppression (AI-VS) and automatic detection (AI-AD) algorithm can improve detection of subsolid nodules (SSNs) on LDCT. We assessed the impact of AI-VS and AI-AD in detection and classification of SSNs [ground-glass nodules (GGNs) and part-solid nodules (PSNs)], on LDCT performed for LCS. METHODS: Following regulatory approval, 123 LDCT examinations with sub-solid pulmonary nodules (average diameter ≥6 mm) were processed to generate three image series for each examination-unprocessed, AI-VS, and AI-AD series with annotated lung nodules. Two thoracic radiologists in consensus formed the standard of reference (SOR) for this study. Two other thoracic radiologists (R1 and R2; 5 and 10 years of experience in thoracic CT image interpretation) independently assessed the unprocessed images alone, then together with AI-VS series, and finally with AI-AD for detecting all ≥6 mm GGN and PSN. We performed receiver operator characteristics (ROC) and Cohen's Kappa analyses for statistical analyses. RESULTS: On unprocessed images, R1 and R2 detected 232/310 nodules (R1: 114 GGN, 118 PSN) and 255/310 nodules (R2: 122 GGN, 133 PSN), respectively (P>0.05). On AI-VS images, they detected 249/310 nodules (119 GGN, 130 PSN) and 277/310 nodules (128 GGN, 149 PSN), respectively (P≥0.12). When compared to the SOR, accuracy (AUC) for detection of PSN on the AI-VS images (AUC 0.80-0.81) was greater than on the unprocessed images (AUC 0.70-0.76). AI-VS images enabled detection of solid components in five nodules deemed as GGN on the unprocessed images. Accuracy of AI-AD was lower than both the radiologists (AUC 0.60-0.72). CONCLUSIONS: AI-VS improved the detection and classification of SSN into GGN and PSN on LDCT of the chest for the two radiologist (R1 and R2) readers.

Comparison of Chest CT Findings of COVID-19, Influenza, and Organizing Pneumonia: A Multireader Study.

BACKGROUND. Previous studies compared CT findings of COVID-19 pneumonia with those of other infections; however, to our knowledge, no studies to date have included noninfectious organizing pneumonia (OP) for comparison. OBJECTIVE. The objectives of this study were to compare chest CT features of COVID-19, influenza, and OP using a multireader design and to assess the performance of radiologists in distinguishing between these conditions. METHODS. This retrospective study included 150 chest CT examinations in 150 patients (mean [± SD] age, 58 ± 16 years) with a diagnosis of COVID-19, influenza, or non-infectious OP (50 randomly selected abnormal CT examinations per diagnosis). Six thoracic radiologists independently assessed CT examinations for 14 individual CT findings and for Radiological Society of North America (RSNA) COVID-19 category and recorded a favored diagnosis. The CT characteristics of the three diagnoses were compared using random-effects models; the diagnostic performance of the readers was assessed. RESULTS. COVID-19 pneumonia was significantly different (p < .05) from influenza pneumonia for seven of 14 chest CT findings, although it was different (p < .05) from OP for four of 14 findings (central or diffuse distribution was seen in 10% and 7% of COVID-19 cases, respectively, vs 20% and 21% of OP cases, respectively; unilateral distribution was seen in 1% of COVID-19 cases vs 7% of OP cases; non-tree-in-bud nodules was seen in 32% of COVID-19 cases vs 53% of OP cases; tree-in-bud nodules were seen in 6% of COVID-19 cases vs 14% of OP cases). A total of 70% of cases of COVID-19, 33% of influenza cases, and 47% of OP cases had typical findings according to RSNA COVID-19 category assessment (p < .001). The mean percentage of correct favored diagnoses compared with actual diagnoses was 44% for COVID-19, 29% for influenza, and 39% for OP. The mean diagnostic accuracy of favored diagnoses was 70% for COVID-19 pneumonia and 68% for both influenza and OP. CONCLUSION. CT findings of COVID-19 substantially overlap with those of influenza and, to a greater extent, those of OP. The diagnostic accuracy of the radiologists was low in a study sample that contained equal proportions of these three types of pneumonia. CLINICAL IMPACT. Recognized challenges in diagnosing COVID-19 by CT are furthered by the strong overlap observed between the appearances of COVID-19 and OP on CT. This challenge may be particularly evident in clinical settings in which there are substantial proportions of patients with potential causes of OP such as ongoing cancer therapy or autoimmune conditions.

Google search volume trends for cancer screening terms during the COVID-19 pandemic.

The COVID-19 pandemic has led to delays in cancer diagnosis, in part due to postponement of cancer screening. We used Google Trends data to assess public attention to cancer screening during the first peak of the COVID-19 pandemic. Search volume for terms related to established cancer screening tests ("colonoscopy," "mammogram," "lung cancer screening," and "pap smear") showed a marked decrease of up to 76% compared to the pre-pandemic period, a significantly greater drop than for search volume for terms denoting common chronic diseases. Maintaining awareness of cancer screening during future public health crises may decrease delays in cancer diagnosis.

Addressing Linguistic Barriers to Care: Evaluation of Breast Cancer Online Patient Educational Materials for Spanish-Speaking Patients.

PURPOSE: The purpose of this study was to evaluate the readability of breast cancer online patient educational materials (OPEM) written in Spanish and to compare to equivalent English-language OPEM. METHODS: The breast cancer-related terms cáncer de seno (breast cancer), detección de cáncer de seno (breast cancer screening), and biopsia de seno (breast biopsy) were queried using an online search engine. After each query, educational information related to the queried term was downloaded from each website appearing on the first five search engine result pages. Readability of Spanish-language OPEM was evaluated using the Crawford reading grade score. When available, equivalent English-language OPEM from the same website was then evaluated using the mean of five validated readability indices. Differences in readability, word count, and reading time between Spanish- and English-language OPEM were compared using an unpaired t test. The Fisher exact test was used to compare the proportion of websites meeting AMA recommendations for patient educational resources. RESULTS: Queries for cáncer de seno, detección de cáncer de seno, and biopsia de seno yielded 27, 31, and 30 results of term-specific OPEM. Equivalent English-language versions were available for 19 (70.4%), 18 (58.1%), and 20 (66.7%) websites, respectively. Spanish-language OPEM were written at a lower grade reading level than equivalent English-language versions overall (5.49 ± 0.50 versus 7.77 ± 1.95, P < .01). Spanish-language OPEM were also more likely than English-language OPEM to meet AMA recommendations (82.9% versus 40.4%, P < .01). CONCLUSIONS: Breast cancer-related Spanish-language OPEM were written at a significantly lower grade reading level compared with equivalent information written in English.

Coronary artery calcification in COVID-19 patients: an imaging biomarker for adverse clinical outcomes.

BACKGROUND: Recent studies have demonstrated a complex interplay between comorbid cardiovascular disease, COVID-19 pathophysiology, and poor clinical outcomes. Coronary artery calcification (CAC) may therefore aid in risk stratification of COVID-19 patients. METHODS: Non-contrast chest CT studies on 180 COVID-19 patients ≥ age 21 admitted from March 1, 2020 to April 27, 2020 were retrospectively reviewed by two radiologists to determine CAC scores. Following feature selection, multivariable logistic regression was utilized to evaluate the relationship between CAC scores and patient outcomes. RESULTS: The presence of any identified CAC was associated with intubation (AOR: 3.6, CI: 1.4-9.6) and mortality (AOR: 3.2, CI: 1.4-7.9). Severe CAC was independently associated with intubation (AOR: 4.0, CI: 1.3-13) and mortality (AOR: 5.1, CI: 1.9-15). A greater CAC score (UOR: 1.2, CI: 1.02-1.3) and number of vessels with calcium (UOR: 1.3, CI: 1.02-1.6) was associated with mortality. Visualized coronary stent or coronary artery bypass graft surgery (CABG) had no statistically significant association with intubation (AOR: 1.9, CI: 0.4-7.7) or death (AOR: 3.4, CI: 1.0-12). CONCLUSION: COVID-19 patients with any CAC were more likely to require intubation and die than those without CAC. Increasing CAC and number of affected arteries was associated with mortality. Severe CAC was associated with higher intubation risk. Prior CABG or stenting had no association with elevated intubation or death.