Joint EANM-SNMMI guideline on the role of 2-[18F]FDG PET/CT in no special type breast cancer : (endorsed by the ACR, ESSO, ESTRO, EUSOBI/ESR, and EUSOMA).

INTRODUCTION: There is much literature about the role of 2-[18F]FDG PET/CT in patients with breast cancer (BC). However, there exists no international guideline with involvement of the nuclear medicine societies about this subject. PURPOSE: To provide an organized, international, state-of-the-art, and multidisciplinary guideline, led by experts of two nuclear medicine societies (EANM and SNMMI) and representation of important societies in the field of BC (ACR, ESSO, ESTRO, EUSOBI/ESR, and EUSOMA). METHODS: Literature review and expert discussion were performed with the aim of collecting updated information regarding the role of 2-[18F]FDG PET/CT in patients with no special type (NST) BC and summarizing its indications according to scientific evidence. Recommendations were scored according to the National Institute for Health and Care Excellence (NICE) criteria. RESULTS: Quantitative PET features (SUV, MTV, TLG) are valuable prognostic parameters. In baseline staging, 2-[18F]FDG PET/CT plays a role from stage IIB through stage IV. When assessing response to therapy, 2-[18F]FDG PET/CT should be performed on certified scanners, and reported either according to PERCIST, EORTC PET, or EANM immunotherapy response criteria, as appropriate. 2-[18F]FDG PET/CT may be useful to assess early metabolic response, particularly in non-metastatic triple-negative and HER2+ tumours. 2-[18F]FDG PET/CT is useful to detect the site and extent of recurrence when conventional imaging methods are equivocal and when there is clinical and/or laboratorial suspicion of relapse. Recent developments are promising. CONCLUSION: 2-[18F]FDG PET/CT is extremely useful in BC management, as supported by extensive evidence of its utility compared to other imaging modalities in several clinical scenarios.

Can incorrect artificial intelligence (AI) results impact radiologists, and if so, what can we do about it? A multi-reader pilot study of lung cancer detection with chest radiography.

OBJECTIVE: To examine whether incorrect AI results impact radiologist performance, and if so, whether human factors can be optimized to reduce error. METHODS: Multi-reader design, 6 radiologists interpreted 90 identical chest radiographs (follow-up CT needed: yes/no) on four occasions (09/20-01/22). No AI result was provided for session 1. Sham AI results were provided for sessions 2-4, and AI for 12 cases were manipulated to be incorrect (8 false positives (FP), 4 false negatives (FN)) (0.87 ROC-AUC). In the Delete AI (No Box) condition, radiologists were told AI results would not be saved for the evaluation. In Keep AI (No Box) and Keep AI (Box), radiologists were told results would be saved. In Keep AI (Box), the ostensible AI program visually outlined the region of suspicion. AI results were constant between conditions. RESULTS: Relative to the No AI condition (FN = 2.7%, FP = 51.4%), FN and FPs were higher in the Keep AI (No Box) (FN = 33.0%, FP = 86.0%), Delete AI (No Box) (FN = 26.7%, FP = 80.5%), and Keep AI (Box) (FN = to 20.7%, FP = 80.5%) conditions (all ps < 0.05). FNs were higher in the Keep AI (No Box) condition (33.0%) than in the Keep AI (Box) condition (20.7%) (p = 0.04). FPs were higher in the Keep AI (No Box) (86.0%) condition than in the Delete AI (No Box) condition (80.5%) (p = 0.03). CONCLUSION: Incorrect AI causes radiologists to make incorrect follow-up decisions when they were correct without AI. This effect is mitigated when radiologists believe AI will be deleted from the patient's file or a box is provided around the region of interest. CLINICAL RELEVANCE STATEMENT: When AI is wrong, radiologists make more errors than they would have without AI. Based on human factors psychology, our manuscript provides evidence for two AI implementation strategies that reduce the deleterious effects of incorrect AI. KEY POINTS: • When AI provided incorrect results, false negative and false positive rates among the radiologists increased. • False positives decreased when AI results were deleted, versus kept, in the patient's record. • False negatives and false positives decreased when AI visually outlined the region of suspicion.

FDG PET in Evaluation of Patients With Fever of Unknown Origin: AJR Expert Panel Narrative Review.

Fever of unknown origin (FUO) is a diagnostic challenge, with its cause remaining undiagnosed in approximately half of patients. Nuclear medicine tests typically are performed after a negative or inconclusive initial workup. Gallium-67 citrate and labeled leukocytes were previous mainstays of radionuclide imaging for FUO, although they had limited diagnostic performance. FDG PET/CT has subsequently emerged as the nuclear medicine imaging test of choice, supported by a growing volume of evidence. A positive FDG PET/CT result contributes useful information by identifying potential causes of fever, localizing sites for further evaluation, and guiding further management; a negative result contributes useful information by excluding focal disease as the cause of fever and predicts a favorable prognosis. In 2021, CMS rescinded a prior national noncoverage determination for FDG PET for infection and inflammation, leading to increasing national utilization of FDG PET/CT for FUO workup. This article reviews the current status of the role of FDG PET/CT in the evaluation of patients with FUO. The literature reporting the diagnostic performance and yield of FDG PET/CT in FUO workup is summarized, with comparison with historically used nuclear medicine tests included. Attention is also given to the test's clinical impact; protocol, cost, and radiation considerations; and application in children.

Imaging and Management of Radial Scars and Complex Sclerosing Lesions.

Radial scars and complex sclerosing lesions, often collectively referred to as radial sclerosing lesions (RSLs), are breast lesions characterized by sclerotic stroma with entrapped epithelial elements. RSLs have imaging features that overlap with those of breast malignancy and often become the target of imaging-guided biopsy given their suspicious imaging appearance. These can be identified in isolation or can also be associated with atypia or other high-risk lesions that have intrinsic malignant potential, increasing the risk of carcinoma and affecting prognosis and management of RSLs. Because of this, management of these lesions remains controversial. Traditional management has been surgical excisional biopsy. However, as more RSLs are identified (because digital breast tomosynthesis allows identification of more architectural distortions), optimal management is evolving. Physicians in some practices are using a multidisciplinary approach to the management of RSLs when deciding on surgical excision of these lesions versus imaging follow-up. These discussions also incorporate individual patient risk factors and greater patient informed medical decision making. Reported upgrade rates of RSLs at core needle biopsy vary and can depend on the sampling method, number of samples, gauge of the needle, target being sampled, and radiologic-pathologic concordance or discordance. A precise sampling technique also allows greater accuracy of diagnosis and lower upgrade rates for these lesions, with radiologic-pathologic correlation as an integral component for further management decisions. The authors review the overall histopathologic, clinical, and imaging features of RSLs and discuss appropriate management based on currently available data regarding upgrade rates. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Imaging a Fever-Redefining the Role of 2-deoxy-2-[18F]Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography in Fever of Unknown Origin Investigations.

Growing evidence suggests that 2-deoxy-2-[18F]fluoro-D-glucose (18FDG)-positron emission tomography/computed tomography (PET/CT) is a useful imaging technique for the evaluation of fever of unknown origin (FUO). This imaging technique allows for accurate localization of foci of hypermetabolism based on 18FDG uptake in glycolytically active cells that may represent inflammation, infection, or neoplasia. The presence of abnormal uptake can help direct further investigation that may yield a final diagnosis. A lack of abnormal uptake can be reasonably reassuring that these conditions are not present, thereby avoiding unnecessary additional testing. Insurers have not routinely covered outpatient 18FDG-PET/CT for the indication of FUO in the United States. However, data published since 2007 suggest early use in FUO diagnostic evaluations improves diagnostic efficiency and reduces costs. Clinicians and insurers should consider 18FDG-PET/CT as a useful tool when preliminary studies are unrevealing.

Considerations in Specialty Selections: What Medical Students Think, Know, and Think They Know about Interventional Radiology.

PURPOSE: To compare the motivation, deterrents, knowledge, exposure, and other specialty considerations of first- to fourth-year medical students interested in interventional radiology (IR) with those who are not. MATERIALS AND METHODS: Matriculants of 5 medical schools varying by region, public/private, class size, and National Institutes of Health research ranking received a 19-question survey with questions about demographics, specialty interests, motivations/deterrents, knowledge, and exposure to IR. RESULTS: A total of 25.8% (611/2370) of students completed the survey, of which 20.5% (125/611) expressed interest in IR, and 25% (47/186), 26% (40/153), 24% (34/143), and 3% (3/117) of first-year, second-year, third-year, and fourth-year medical students, respectively, were seriously considering IR. Those interested in IR were less motivated by direct patient care (mean, 2.8/5; 95% confidence interval [CI], 2.6-3.0) and longitudinal patient care (mean, 1.6/5; 95% CI, 1.4-1.7) (both, P < .01) and more motivated by salary (2.6/5; 95% CI, 2.3-2.9), job market (2.8/5; 95% CI, 2.6-2.9), and procedures (3.1/5; 95% CI, 2.8-3.4) compared with their peers (all P < .05). Those interested in IR were more certain about their IR knowledge (mean range, 1.6-2.0/3.0; 95% CI, 1.3-2.3) than their peers (mean range, 1.9-2.4/3.0; 95% CI, 1.6-2.1, in which 0 = certain, P ≤ .01); however, both groups scored low in actual knowledge (those considering IR: 35.0-73.2% correct; 95% CI, 23.5-81.4; those who were not: 26.6-66.7% correct; 95% CI, 24.3-75.9, P > .05). CONCLUSIONS: Although medical students showed interest in IR, they had a limited understanding of IR. IR educators may increase IR interest and understanding among medical students by clarifying the procedural aspects and longitudinal care present in a comprehensive IR practice.

Survey of radiologists and emergency department providers after implementation of a global radiology report categorization system.

PURPOSE: Breakdown in communication of important imaging results threatens patient safety and risks malpractice claims. To facilitate closed-loop communication, our institution developed a unique radiology report categorization (RADCAT) system employing automated alert notification systems. This study aimed to understand users' initial experiences with the RADCAT system and obtain feedback. METHODS: Web-based surveys were distributed to radiologists and emergency department (ED) providers at our hospital system within 1 year of institution-wide RADCAT implementation. Survey designs differed based on clinical setting. Most prompts utilized declarative statements with 5-point agreement Likert scales. Closed-response data was analyzed with descriptive statistics. RESULTS: Response rates among radiologists and ED providers were 59.4% (63/106) and 38.4% (69/211), respectively. 78.0% (46/59) of radiologists and 60.9% (42/69) of ED providers agreed that RADCAT improves patient care. Of radiologists, 84.1% (53/63) agreed that RADCAT design is intuitive, and 57.6% (34/59) agreed that RADCAT improves efficiency. Of ED providers, 69.6% (48/69) agreed that RADCAT appropriately differentiates urgent and non-urgent findings, and 65.2% (45/69) agreed that auto-population of discharge documents with imaging results containing follow-up recommendations protects them from liability. Only 35.6% (21/59) of radiologists and 21.7% (15/69) of ED providers agreed that RADCAT implementation decreased reading room visits by ordering providers. Open-response feedback showed that some ED providers find RADCAT too complex while some radiologists desire improved transparency regarding imaging study communication status. CONCLUSION: Since its implementation, RADCAT has been well received among radiologists and ED providers with agreement that it improves patient care and effectively distinguishes and communicates important imaging findings.

Molecular Breast Imaging in Clinical Practice.

OBJECTIVE. The purpose of this article is to review clinical uses and image interpretation of molecular breast imaging (MBI) and clarify radiation risks. CONCLUSION. MBI detects additional cancers compared with conventional imaging in women with dense breasts and those with elevated risk of breast cancer. Its role as an imaging biomarker of cancer risk and in assessing neoadjuvant chemotherapy response is growing. Radiation risk is minimal; benefit-to-risk ratio is similar to that of mammography. MBI is low cost, well tolerated, and easily adapted into clinical practice.

Readability of Online Patient Educational Materials Related to Breast Lesions Requiring Surgery.

Purpose To evaluate readability of websites that are commonly accessed for information on breast lesions requiring surgery. Materials and Methods An internet search using three malignant and eight nonmalignant breast lesions that traditionally require lumpectomy or excisional biopsy as search terms was conducted to identify websites commonly accessed for patient information on breast lesions requiring surgery. Nine websites with information on breast diagnoses were identified based on search engine results for each breast lesion queried. Available patient-directed information was downloaded for each lesion from each website on May 15, 2018. Grade-level readability of downloaded content for each lesion was then determined by using generalized estimating equations, with observations nested within readability metrics from each website. Readability of associated terms breast biopsy, breast cancer, and breast surgery was also evaluated with the same method. Results were compared with American Medical Association (AMA) recommended readability parameters (sixth-grade reading level). All interval estimates were calculated for 95% confidence. Results Average grade level readability score of health information on breast lesions requiring surgery was 11.7, which exceeded the AMA parameters. Information on Wikipedia was written at the highest reading level (grade level readability score, 14.2), while information on the National Institutes of Health website ( http://cancer.gov ) was written at the lowest reading level (grade level readability score, 9.7). Educational materials on malignant breast lesions (grade level readability score, 12.3) were written at a higher reading level than were those on nonmalignant breast lesions (grade level readability score,11.4). Information on the terms breast biopsy (grade level readability score, 10.9), breast cancer (grade level readability score, 10.6), and breast surgery (grade level readability score, 11.1) were all written above a sixth-grade reading level. Conclusion Readability of current online resources on breast biopsy lesions traditionally requiring surgery may be too complex for the general public to comprehend, leading to misinformation and confusion. © RSNA, 2019 See also the editorial by Haygood in this issue.

FDG PET/CT of Infection: Should It Replace Labeled Leukocyte Scintigraphy of Inpatients?

OBJECTIVE. The purpose of this study was to compare the sensitivity, specificity, and helpfulness to referring clinicians of labeled leukocyte scintigraphy versus FDG PET/CT in inpatients with suspected infection. MATERIALS AND METHODS. In this retrospective study, labeled leukocyte scintigraphy and FDG PET/CT examinations performed from 2009 to 2017 for suspected infection in inpatients were identified. Sensitivity, specificity, and helpfulness of PET/CT versus labeled leukocyte scintigraphy were calculated by means of a mixed generalized linear model. Number of yearly tests and radiopharmaceutical costs were also assessed. RESULTS. Fifty-seven patients (30 men, 27 women; median age, 65 years; range, 21-91 years) underwent whole-body labeled leukocyte scintigraphy. Forty-two patients (30 male patients, 12 female patients; median age, 62.5 years; range, 12-91 years) underwent PET/CT for suspected infection. Labeled leukocyte scintigraphy was 66.7% sensitive, whereas the sensitivity of PET/CT was 89.7% (p = 0.0485). The higher sensitivity of PET/CT did not come at a cost to specificity, which was 73.3% as opposed to 76.9% for labeled leukocyte scintigraphy (p = 0.8050). The odds of a positive study being helpful increased 4.6-fold for PET/CT versus labeled leukocyte scintigraphy (p = 0.0412). From 2009 to 2011, 33 labeled leukocyte scintigraphic examinations were performed versus two PET/CT examinations; and from 2012 to 2014, 16 labeled leukocyte scintigraphic versus 22 PET/CT examinations; from 2015 to 2017, eight labeled leukocyte scintigraphic versus 18 PET/CT examinations. The cost of labeled leukocytes increased between 2009 and 2017, but that of FDG decreased. By 2017, a labeled leukocyte radiopharmaceutical dose was approximately 10 times the cost of an FDG dose. CONCLUSION. PET/CT was more sensitive than and as specific as labeled leukocyte scintigraphy for identifying a source of infection in inpatients, and it was more helpful to referring clinicians. Use of PET/CT increased over time and was associated with substantial savings in radiopharmaceutical cost.

Dense Breast Ultrasound Screening After Digital Mammography Versus After Digital Breast Tomosynthesis.

OBJECTIVE. The objective of this study was to compare the yield of dense breast ultrasound (US) screening after digital mammography (DM) versus after digital breast tomosyn-thesis (DBT). MATERIALS AND METHODS. For this institutional review board-approved, HIPAA-compliant study, we retrospectively searched databases at two tertiary breast imaging centers and an office practice staffed by the same fellowship-trained breast radiologists for screening US examinations from October 1, 2014, to September 30, 2016. Prior DM versus DBT and screening US and pathology results were recorded. Mammographically occult cancers detected with US and additional benign lesions requiring biopsy were calculated. Differences between DM and DBT were compared using the two-sample proportions z test. RESULTS. A total of 3183 screening breast US examinations were performed, 1434 (45.1%) after DM and 1668 (52.4%) after DBT. Of the 3183 examinations, 81 (2.5%) had no prior mammogram available. Of the 122 DM and DBT patients for whom biopsy or cyst aspiration was recommended (all BI-RADS assessment category 4 or BI-RADS assessment category 5 studies), 118 (96.7%) had biopsy or cyst aspiration results available. Of the 36 biopsies or aspirations after DM, 6 (16.7%) were malignant and 30 (83.3%) were benign; of the 82 biopsies or aspirations after DBT, 11 (13.4%) were malignant and 71 (86.6%) were benign (p = 0.8583). The additional cancer detection rate by US after DM was 5/1434 or 3.5 per 1000 women screened and after DBT was 5/1668 or 3.0 per 1000 women screened (p = 0.9999). CONCLUSION. No significant difference in additional cancer detection rate was found with screening US after DM versus after DBT.

Effectiveness of a Staged US and Unenhanced MR Imaging Algorithm in the Diagnosis of Pediatric Appendicitis.

Purpose To establish, in a large cohort, the diagnostic performance of a staged algorithm involving ultrasonography (US) followed by conditional unenhanced magnetic resonance (MR) imaging for the imaging work-up of pediatric appendicitis. Materials and Methods A staged imaging algorithm in which US and unenhanced MR imaging were performed in pediatric patients suspected of having appendicitis was implemented at the authors' institution on January 1, 2011, with US as the initial modality followed by unenhanced MR imaging when US findings were equivocal. A search of the radiology database revealed 2180 pediatric patients who had undergone imaging for suspected appendicitis from January 1, 2011, through December 31, 2012. Of the 2180 patients, 1982 (90.9%) were evaluated according to the algorithm. The authors reviewed the electronic medical records and imaging reports for all patients. Imaging reports were reviewed and classified as positive, negative, or equivocal for appendicitis and correlated with surgical and pathology reports. Results The frequency of appendicitis was 20.5% (407 of 1982 patients). US alone was performed in 1905 of the 1982 patients (96.1%), yielding a sensitivity of 98.7% (386 of 391 patients) and specificity of 97.1% (1470 of 1514 patients) for appendicitis. Seventy-seven patients underwent unenhanced MR imaging after equivocal US findings, yielding an overall algorithm sensitivity of 98.2% (400 of 407 patients) and specificity of 97.1% (1530 of 1575 patients). Seven of the 1982 patients (0.4%) had false-negative results with the staged algorithm. The negative predictive value of the staged algorithm was 99.5% (1530 of 1537 patients). Conclusion A staged algorithm of US and unenhanced MR imaging for pediatric appendicitis appears to be effective. The results of this study demonstrate that this staged algorithm is 98.2% sensitive and 97.1% specific for the diagnosis of appendicitis in pediatric patients. © RSNA, 2017.

Comparison of digital mammography and digital breast tomosynthesis in the detection of architectural distortion.

OBJECTIVES: To compare interobserver variability (IOV), reader confidence, and sensitivity/specificity in detecting architectural distortion (AD) on digital mammography (DM) versus digital breast tomosynthesis (DBT). METHODS: This IRB-approved, HIPAA-compliant reader study used a counterbalanced experimental design. We searched radiology reports for AD on screening mammograms from 5 March 2012-27 November 2013. Cases were consensus-reviewed. Controls were selected from demographically matched non-AD examinations. Two radiologists and two fellows blinded to outcomes independently reviewed images from two patient groups in two sessions. Readers recorded presence/absence of AD and confidence level. Agreement and differences in confidence and sensitivity/specificity between DBT versus DM and attendings versus fellows were examined using weighted Kappa and generalised mixed modeling, respectively. RESULTS: There were 59 AD patients and 59 controls for 1,888 observations (59 × 2 (cases and controls) × 2 breasts × 2 imaging techniques × 4 readers). For all readers, agreement improved with DBT versus DM (0.61 vs. 0.37). Confidence was higher with DBT, p = .001. DBT achieved higher sensitivity (.59 vs. .32), p < .001; specificity remained high (>.90). DBT achieved higher positive likelihood ratio values, smaller negative likelihood ratio values, and larger ROC values. CONCLUSIONS: DBT decreases IOV, increases confidence, and improves sensitivity while maintaining high specificity in detecting AD. KEY POINTS: • Digital breast tomosynthesis decreases interobserver variability in the detection of architectural distortion. • Digital breast tomosynthesis increases reader confidence in the detection of architectural distortion. • Digital breast tomosynthesis improves sensitivity in the detection of architectural distortion.

Automated Delivery of Clinical Follow-Up to the Radiologist via E-Mail: Feasibility Study of a New Information Technology Algorithm.

OBJECTIVE: The purposes of this study were to develop an automated process for radiologists to obtain clinical follow-up on radiology reports via HIPAA-compliant e-mail and to determine what follow-up data were collected and whether they were relevant to the radiology reports. CONCLUSION: The algorithm generated high-yield follow-up data for radiologists that may improve patient care by facilitating radiologist engagement and self-assessment.

Cryoablation of Abdominal Wall Endometriosis: A Minimally Invasive Treatment.

OBJECTIVE: The objective of this study is to present cryoablation as a minimally invasive definitive treatment for abdominal wall endometriosis. We describe our experience with the outpatient application of cryoablation to treat symptomatic abdominal wall endometriosis in three patients. CONCLUSION: This feasibility study shows that minimally invasive cryoablation treated abdominal wall endometriosis in three patients and provided a prompt clinical response.

The RADCAT-3 system for closing the loop on important non-urgent radiology findings: a multidisciplinary system-wide approach.

The goal of this project was to create a system that was easy for radiologists to use and that could reliably identify, communicate, and track communication of important but non-urgent radiology findings to providers and patients. Prior to 2012, our workflow for communicating important non-urgent diagnostic imaging results was cumbersome, rarely used by our radiologists, and resulted in delays in report turnaround time. In 2012, we developed a new system to communicate important non-urgent findings (the RADiology CATegorization 3 (RADCAT-3) system) that was easy for radiologists to use and documented communication of results in the electronic medical record. To evaluate the performance of the new system, we reviewed our radiology reports before (June 2011-June 2012) and after (June 2012-June 2014) the implementation of the new system to compare utilization by the radiologists and success in communicating these findings. During the 12 months prior to implementation, 250 radiology reports (0.06 % of all reports) entered our workflow for communicating important non-urgent findings. One-hundred percent were successfully communicated. During the 24 months after implementation, 13,158 radiology reports (1.4 % of all reports) entered our new RADCAT-3 workflow (3995 (0.8 % of all reports) during year 1 and 9163 (1.9 % of all reports) during year 2). 99.7 % of those reports were successfully communicated. We created a reliable system to ensure communication of important but non-urgent findings with providers and/or patients and to document that communication in the electronic medical record. The rapid adoption of the new system by radiologists suggests that they found it easy to use and had confidence in its integrity. This system has the potential to improve patient care by improving the likelihood of appropriate follow-up for important non-urgent findings that could become life threatening.

Imaging Unusual Pregnancy Implantations: Rare Ectopic Pregnancies and More.

OBJECTIVE: The purpose of this article is to review key clinical issues and imaging features of unusual pregnancy implantations. Examples from different imaging modalities are provided to increase interpreting physicians' familiarity with the appearance and potential complications of unusual ectopic, cesarean scar, heterotopic, and rudimentary horn pregnancies. CONCLUSION: Abnormal pregnancy implantations are life-threatening. Interpreting physicians' familiarity with the appearance of unusual pregnancy implantations is critical for early identification and initiation of appropriate therapy.