Paraneoplastic Syndromes from Head to Toe: Pathophysiology, Imaging Features, and Workup.

Patients often have symptoms due to the mass effect of a neoplasm on surrounding tissues or the development of distant metastases. However, some patients may present with clinical symptoms that are not attributable to direct tumor invasion. In particular, certain tumors may release substances such as hormones or cytokines or trigger an immune cross-reactivity between malignant and normal body cells, resulting in characteristic clinical features that are broadly referred to as paraneoplastic syndromes (PNSs). Recent advances in medicine have improved the understanding of the pathogenesis of PNSs and enhanced their diagnosis and treatment. It is estimated that 8% of patients with cancer develop a PNS. Diverse organ systems may be involved, most notably the neurologic, musculoskeletal, endocrinologic, dermatologic, gastrointestinal, and cardiovascular systems. Knowledge of various PNSs is necessary, as these syndromes may precede tumor development, complicate the patient's clinical presentation, indicate tumor prognosis, or be mistaken for metastatic spread. Radiologists should be familiar with the clinical presentations of common PNSs and the selection of appropriate imaging examinations. Many of these PNSs have imaging features that can assist with arriving at the correct diagnosis. Therefore, the key radiographic findings associated with these PNSs and the diagnostic pitfalls that can be encountered during imaging are important, as their detection can facilitate early identification of the underlying tumor, reveal early recurrence, and enable monitoring of the patient's response to therapy. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Li-Fraumeni Syndrome and Whole-Body MRI Screening: Screening Guidelines, Imaging Features, and Impact on Patient Management.

OBJECTIVE: Li-Fraumeni syndrome (LFS) is a rare autosomal-dominant inherited syndrome containing a germline mutation in the TP53 gene, which predisposes to oncogenesis. Leukemia and tumors of the brain, soft tissues, breasts, adrenal glands, and bone are the most common cancers associated with this syndrome. Patients with LFS are very susceptible to radiation, therefore the use of whole-body MRI is recommended for regular cancer screening. It is important to recognize the common tumors associated with LFS on MRI, and it is also important to be aware of the high rate of false-positive lesions. CONCLUSION: Whole-body MRI is useful for the detection of cancer in patients who come for regular screening; however, it is associated with pitfalls about which the radiologist must remain aware.

Imaging Features at the Periphery: Hemodynamics, Pathophysiology, and Effect on LI-RADS Categorization.

Liver lesions have different enhancement patterns at dynamic contrast-enhanced imaging. The Liver Imaging Reporting and Data System (LI-RADS) applies the enhancement kinetic of liver observations in its algorithms for imaging-based diagnosis of hepatocellular carcinoma (HCC) in at-risk populations. Therefore, careful analysis of the spatial and temporal features of these enhancement patterns is necessary to increase the accuracy of liver mass characterization. The authors focus on enhancement patterns that are found at or around the margins of liver observations-many of which are recognized and defined by LI-RADS, such as targetoid appearance, rim arterial phase hyperenhancement, peripheral washout, peripheral discontinuous nodular enhancement, enhancing capsule appearance, nonenhancing capsule appearance, corona enhancement, and periobservational arterioportal shunts-as well as peripheral and periobservational enhancement in the setting of posttreatment changes. Many of these are considered major or ancillary features of HCC, ancillary features of malignancy in general, features of non-HCC malignancy, features associated with benign entities, or features related to treatment response. Distinction between these different patterns of enhancement can help with achieving a more specific diagnosis of HCC and better assessment of response to local-regional therapy. ©RSNA, 2021.

Calcified Splenic Lesions: Pattern Recognition Approach on CT With Pathologic Correlation.

OBJECTIVE. Incidental splenic lesions, often found on CT images of the abdomen, may often be ignored or mischaracterized. Calcified splenic lesions are often presumed to be granulomas; however, understanding the broader differential diagnostic considerations can be useful. CONCLUSION. Determining the cause of splenic lesions is essential to guide appropriate management; the pattern of calcification together with other imaging and clinical findings can aid with differentiation.

A Review of Viral-Related Malignancies and the Associated Imaging Findings.

OBJECTIVE. Imaging plays an important role in the diagnosis and staging of malignancies. Many common lymphoproliferative and other solid tumor malignancies can be viral-related. CONCLUSION. This review discusses the imaging findings that can be associated with common viral-induced malignancies. Knowledge of these imaging presentations can help narrow the differential diagnosis to reach a specific diagnosis through a precise workup and proper management.

Calcified Adrenal Lesions: Pattern Recognition Approach on Computed Tomography With Pathologic Correlation.

Incidental adrenal lesions are found in 2% to 10% of the population. The presence and pattern of calcifications, in conjunction with other clinical and imaging features, such as soft tissue attenuation, enhancement, and laterality, can aid in narrowing a differential diagnosis, thereby preventing unnecessary biopsies and avoiding delays in management. Calcified adrenal lesions can be categorized under the clinical and laboratory headings of normal adrenal function, hyperfunctioning adrenal tissue, and adrenal insufficiency. In this review, we provide an algorithmic approach to assessing calcified adrenal nodules with correlative radiologic findings.

Inferring Intracellular Signal Transduction Circuitry from Molecular Perturbation Experiments.

The development of network inference methodologies that accurately predict connectivity in dysregulated pathways may enable the rational selection of patient therapies. Accurately inferring an intracellular network from data remains a very challenging problem in molecular systems biology. Living cells integrate extremely robust circuits that exhibit significant heterogeneity, but still respond to external stimuli in predictable ways. This phenomenon allows us to introduce a network inference methodology that integrates measurements of protein activation from perturbation experiments. The methodology relies on logic-based networks to provide a predictive approximation of the transfer of signals in a network. The approach presented was validated in silico with a set of test networks and applied to investigate the epidermal growth factor receptor signaling of a breast epithelial cell line, MFC10A. In our analysis, we predict the potential signaling circuitry most likely responsible for the experimental readouts of several proteins in the mitogen-activated protein kinase and phosphatidylinositol-3 kinase pathways. The approach can also be used to identify additional necessary perturbation experiments to distinguish between a set of possible candidate networks.

What can go wrong when doing right? A pictorial review of iatrogenic genitourinary complications.

A growing number of treatments for genitourinary diseases can result in various iatrogenic complications. Multimodality imaging in the post-procedural setting is essential for early and accurate diagnosis to limit morbidity and mortality. We review common and uncommon treatment-induced pathologies affecting the genitourinary system via a case-based approach. We illustrate notable complications affecting the kidneys, ureters, bladder, and urethra induced by percutaneous procedures, external beam radiation, immunotherapy, laparoscopic/robotic pelvic surgery, and intravesicular BCG. Finally, we provide guidance on optimal imaging techniques for diagnosis and highlight the role of image-guided interventions for mitigation of complications.

Modern glucose-lowering drugs in liver transplant recipients: improvement in weight, glycemic control, and potentially allograft steatosis.

Introduction: Recurrent allograft steatosis occurs in one-third of transplanted livers. Antidiabetic agents like glucagon-like peptide-1 receptor agonists (GLP1RA) and sodium-glucose cotransporter type-2 (SGLT2) inhibitors are effective in the management of obesity and hepatic steatosis in the general population; however, there is limited evidence supporting their use in allograft steatosis. We aimed to evaluate their effects on steatosis, body weight, and glycemic control in liver transplant recipients at our institution. Methods: In this single-center retrospective cohort study of liver transplant recipients currently on a GLP1RA or SGLT2 inhibitor (transplanted 2015-2022), we compared clinical and radiological data before medication use and at follow-up. Differences were compared using Wilcoxon signed-rank test. Results: Thirty-seven liver transplant recipients were taking the agents. Diabetes was the most common indication (n = 33) followed by obesity (n = 4). Median follow up was 427 days (301,798). Among those with documented steatosis (n = 21), steatosis improved in 5, worsened in 4, remained unchanged in 1, and change could not be evaluated in 11 due to lack of comparable pre and post imaging. Average weight loss was 3.2 kg (p < 0.001) and BMI decreased by 1.2 kg/m2 (p < 0.001). Hemoglobin A1c decreased by 0.6 mmol/mol (p = 0.0014), insulin requirement reduced by 7 units/day (p = 0.02), and there was no change in additional antidiabetic medications. Discussion: GLP1RA and SGLT-2 inhibitors are tolerated in transplant patients and result in weight loss and better glycemic control. They are promising agents to treat recurrent or de-novo liver allograft steatosis, but further research is needed to evaluate long-term outcomes in liver transplant recipients.

FDG-Avid Pulmonary Nodules and Tracheobronchial Mural Inflammation in IgG4-Related Disease.

ABSTRACT: We report the case of a 9-year-old girl who presented with acute fevers, cough, and epistaxis with nasal swelling, and found to have a nasal mass. On 18F-FDG PET/CT, she was found to have marked nodal and pulmonary parenchymal disease with diffuse and symmetrical mural FDG uptake within the trachea and bronchial tree. The differential diagnosis was broad, and she was diagnosed with IgG4-RD (IgG4-related disease) and improved on appropriate treatment. To our knowledge, there are only 2 other pediatric cases of IgG4-related pulmonary disease in the literature, and our case serves as a unique constellation of intrapulmonary IgG4-RD imaging findings.

Mitigating Unconscious Bias in Recruitment and Hiring.

Unconscious biases in recruitment and hiring can limit the potential for building a diverse academic and private radiology practice. In the private practice environment of radiology, especially in smaller firms, in which a dysfunctional team can lead to a dysfunctional practice overall, it is especially essential to find the best candidates for the team. Many strategies for mitigating these biases can be employed strategically at multiple levels of the hiring process.

To Sustain or not to Sustain: Varying Educational Sessions on Advanced Imaging of Low Back Pain and R-SCAN.

PURPOSE: The aim is to present our long-term institutional experience on the use of the American College of Radiology's (ACR's) Radiology Support, Communication, and Alignment Network (R-SCAN) via educational presentations and guideline dissemination in sustaining lumbar spine magnetic resonance imaging (MRI) appropriateness for low back pain. METHODS: Initial educational presentations on appropriate use criteria for lumbar spine MRI were given to referring providers at three county clinics in April and May of 2016. A second educational refresher was given to the same 3 clinics in November 2017: Clinic A received guideline dissemination, Clinic B served as a control group, and Clinic C received a refresher presentation. Wilcoxon rank-sum test was used to compare the monthly MRI referral rate and ACR Appropriateness Criteria rating. RESULTS: There was no significant difference in monthly referral rates and ACR Appropriateness Criteria after the second education. Monthly referral rates were significantly lower than the baseline rates before the first education for Clinic A (P <0.001), C (P = 0.004), and the combined total (P = 0.002). ACR Appropriateness Criteria ratings were significantly higher than the baseline ratings before the first education for Clinic C (P = 0.002) and the combined total (P = 0.024). DISCUSSION: After the second education, inappropriateness, and referral rates remained significantly lower when compared to rates before but not after the first education. Radiology Support, Communication, and Alignment Network is an invaluable online tool for both radiology practices and referring clinicians to become familiar in preparing to comply with the Protecting Access to Medicare Act and satisfying the Improvement Activities category of the Merit Based Incentive Payment Systems.