Ultrasound-estimated hepatorenal index: diagnostic performance and interobserver agreement for pediatric liver fat quantification.

BACKGROUND: Semiquantitative and quantitative sonographic techniques have the potential for screening and surveillance of children at risk of nonalcoholic fatty liver disease. OBJECTIVE: To determine diagnostic performance and interobserver agreement of hepatorenal index (HRI) for pediatric ultrasound-based liver fat quantification. MATERIALS AND METHODS: In an institutional review board (IRB)-approved retrospective study (April 2014 to April 2023), children (< 18 years) with clinically performed magnetic resonance imaging (MRI) scans for liver fat quantification were assessed. Inclusion criteria required availability of abdominal ultrasound within 3 months of quantitative MRI. Three blinded readers subjectively assessed for sonographic hepatic steatosis and calculated HRI. MRI proton density fat fraction (PDFF) was the reference standard. Interobserver agreement, correlation with PDFF, and optimal HRI (using ROC analysis) values were analyzed. The significance level was set at p < 0.05. RESULTS: A total of 41 patients (25 male) with median (interquartile range (IQR)) age of 13 (10-15) years were included. Median (IQR) MRI PDFF was 11.30% (2.70-17.95%). Hepatic steatosis distribution by MRI PDFF included grade 0 (34%), grade 1 (15%), grade 2 (22%), and grade 3 (29%) patients. Intraclass correlation coefficient for HRI among the three readers was 0.61 (95% CI 0.43-0.75) (p < 0.001). Moderate correlation was observed between manually estimated HRI and PDFF for each reader (r = 0.62, 0.67, and 0.67; p < 0.001). Optimal HRI cutoff was found to be 1.99 to diagnose hepatic steatosis (sensitivity 89%, specificity 93%). Median (IQR) HRI for each MRI grade of hepatic steatosis (0-4) was as follows: 1.2 (1.1-1.5), 2.6 (1.1-3.3), 3.6 (2.6-5.4), 5.6 (2.6-10.9), respectively (p < 0.001). CONCLUSION: Ultrasound-estimated HRI has moderate interobserver agreement and moderate correlation with MRI-derived PDFF. HRI of 1.99 maximizes accuracy for identifying pediatric liver fat.

Role of ultrasonography (USG) and color Doppler in the evaluation of thyroid nodules and its association with USG-guided FNAC - A cross-sectional study.

Introduction: Thyroid diseases affect approximately 42 million people in India. The majority (15%-40%) of these cases remain asymptomatic and benign and warrant special investigations such as ultrasonography (USG) and fine-needle aspiration cytology (FNAC) for diagnosis. Early diagnosis and management of thyroid disorders determine the disease course in many patients. Objective: To determine the role of USG and color Doppler in the evaluation of thyroid nodules and its association with USG-guided FNAC. Methods: We did a cross-sectional analytical study over 2 years, where we recruited 108 patients with thyroid swelling attending the OPD. We used a semi-structured data collection proforma that captured information on sociodemographic details, clinical symptoms, physical examination, and all ne cessary laboratory investigations. All patients underwent USG, color Doppler, and FNAC as a part of the investigation of thyroid nodules. The diagnostic value of ultrasound and Doppler parameters was assessed in terms of sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for detection of malignancy in comparison to FNAC. Results: Approximately 155 nodules were identified from the selected 108 cases, and the prevalence of malignancy among the selected thyroid nodule patients was found to be 9.1%. We observed that malignant tumors were likely to be solitary with lobulated margins, >2 cm in size with <50% peripheral halo, with markedly hypoechoic, predominantly solid, with nodal involvement and extrathyroidal extension, microcalcifications, and central vascularity. We also observed that tumors that had USG characteristics of being taller than wide (91%), poorly defined margins (92%), marked hypoechoic (95%), and microcalcifications (96%) had the highest diagnostic accuracy in detecting malignancy when compared to FNAC. Conclusion: Thus, through our study findings, we conclude that USG and color Doppler can serve as vital tools for the evaluation of thyroid nodules with high sensitivity and specificity.

Unusual imaging findings associated with abdominal pediatric germ cell tumors.

Germ cell tumors of childhood are tumors arising from germline cells in gonadal or extragonadal locations. Extragonadal germ cell tumors are characteristically located in the midline, arising intracranially or in the mediastinum, retroperitoneum, or pelvis. These tumors are generally easily diagnosed due to typical sites of origin, characteristic imaging findings, and laboratory markers. However, germ cell tumors can be associated with unusual clinical syndromes or imaging features that can perplex the radiologist. This review will illustrate atypical imaging/clinical manifestations and complications of abdominal germ cell tumors in childhood. These features include unusual primary tumors such as multifocal primaries; local complications such as ovarian torsion or ruptured dermoid; atypical presentations of metastatic disease associated with burned-out primary tumor, growing teratoma syndrome, and gliomatosis peritonei; endocrine manifestations such as precocious puberty and hyperthyroidism; and antibody mediated paraneoplastic syndrome such as anti-N-methyl-D-aspartate-receptor antibody-mediated encephalitis. This review aims to illustrate unusual imaging features associated with the primary tumor, metastatic disease, or distant complications of abdominal germ cell tumors of childhood.

Treatment and outcomes of clear cell sarcoma of the kidney: A report from the Children's Oncology Group studies AREN0321 and AREN03B2.

BACKGROUND: On the fifth National Wilms Tumor Study, treatment for clear cell sarcoma of the kidney (CCSK) included combined vincristine, doxorubicin, cyclophosphamide, and etoposide (regimen I) plus radiation therapy (RT), yielding 5-year event-free survival (EFS) rates of 100%, 88%, 73%, and 29% for patients who had with stage I, II, III, and IV disease, respectively. In the Children's Oncology Group study AREN0321 of risk-adapted therapy, RT was omitted for stage I disease if lymph nodes were sampled, and carboplatin was added for stage IV disease (regimen UH-1). Patients who had stage II/III disease received regimen I with RT. METHODS: Four-year EFS was analyzed for patients enrolled on AREN0321 and on those enrolled on AREN03B2 who received AREN0321 stage-appropriate chemotherapy. RESULTS: Eighty-two patients with CCSK enrolled on AREN0321, 50 enrolled on AREN03B2 only. The 4-year EFS rate was 82.7% (95% confidence interval [CI], 74.8%-91.4%) for AREN0321 and 89.6% (95% CI, 81.3%-98.7%) for AREN03B2 only (p = .28). When combining studies, the 4-year EFS rates for patients who had stage I (n = 10), II (n = 47), III (n = 65), and IV (n = 10) disease were 90% (95% CI, 73.2%-100.0%), 93.4% (95% CI, 86.4%-100.0%), 82.8% (95% CI, 74.1%-92.6%), and 58.3% (95% CI, 34%-100.0%), respectively. There were no local recurrences among seven patients with stage I disease who were treated without RT. One stage I recurrence occurred in the brain, which was the most common site of relapse overall. Among patients with local stage III tumors, neither initial procedure type, margin status, nor lymph node involvement were prognostic. CONCLUSIONS: Patients with stage I CCSK had excellent outcomes without local recurrences when treated without RT. Patients with stage IV disease appeared to benefit from a carboplatin-containing regimen, although their outcomes remained unsatisfactory. Further research is needed to improve outcomes for patients with advanced-stage disease (ClinicalTrials.gov identifiers NCT00335556 and NCT00898365).

Treatment of children with favorable histology Wilms tumor with extrapulmonary metastases: A report from the COG studies AREN0533 and AREN03B2 and NWTSG study NWTS-5.

BACKGROUND: Patients with stage IV favorable histology Wilms tumor (FHWT) with extrapulmonary metastases (EPM) constitute a small subset of patients with FHWT. Because of their rarity and heterogeneity, optimal FHWT treatment is not well understood. Children's Oncology Group protocol AREN0533 assigned patients with FHWT and EPM to intensified chemotherapy, regimen M, after initial DD-4A chemotherapy. To improve understanding of prognostic factors and best therapies, experiences of patients with EPM on AREN0533, as well as on protocols AREN03B2 and NWTS-5, were reviewed. METHODS: Combined outcomes for patients with EPM from NWTS-5, AREN0533, and AREN03B2 were determined. Those treated on AREN0533 were compared with those treated on NWTS-5. Prognostic factors were explored in the pooled cohort. RESULTS: Forty-seven patients with FHWT with EPM enrolled on AREN0533, 37 enrolled on NWTS-5, and 64 were followed only on AREN03B2. The pooled cohort of all 148 patients demonstrated a 4-year event-free survival (EFS) of 77.3% (95% CI, 70.8-84.4) and 4-year overall survival of 88.9% (95% CI, 83.9-94.2). Four-year EFS of patients with EPM treated on AREN0533 was 76.0% (95% CI, 64.6-89.4) vs 64.9% (95% CI, 51.7-82.2) on NWTS-5; hazard ratio, 0.64, p = .26; no difference in overall survival was observed. Increasing linear age and slow incomplete lung response were associated with worse EFS in a pooled cohort. CONCLUSIONS: Outcomes for patients with EPM are among the lowest for children with FHWT. Further trials with standardized surgical and radiation treatment to metastatic sites, and prospectively collected biologic and treatment details are needed. CLINICAL TRIAL REGISTRATION: Clinical Trials.gov identifiers: NCT00379340, NCT00898365, and NCT00002611.

Disparities in paediatric radiology research publications from low- and lower middle-income countries: a time for change.

The positive impact of diversity on health research and outcomes is well-recognised and widely published. Despite this, published evidence shows that at every step of the research pathway, issues of equity, diversity and inclusion (EDI) arise. There is evidence of a lack of diversity within research teams, in the research questions asked/research participants recruited, on grant review/funding panels, amongst funded researchers and on the editorial boards and reviewer pools of the journals to which results are submitted for peer-reviewed publication. Considering the journal Pediatric Radiology, while its editorial board of 92 members has at least one member affiliated to a country in every region of the world, the majority are in North America (n=52, 57%) and Europe (n=30, 33%) and only two (2%) are affiliated to institutions in a lower middle-income country (LMIC) (India, Nigeria), with one (1%) affiliated to an institution in an upper middle-income country (UMIC) (Peru) and none in a low-income country (LIC). Pediatric Radiology is "…the official journal of the European Society of Paediatric Radiology, the Society for Pediatric Radiology, the Asian and Oceanic Society for Pediatric Radiology and the Latin American Society of Pediatric Radiology". However, of the total number of manuscripts submitted for potential publication in the four years 2019 through 2022, only 0.03% were from a LIC and only 7.9% were from a LMIC. Further, the frequency of acceptance of manuscripts from UMIC was seven times higher than that from LMIC (no manuscripts were published from LIC). Increased collaboration is required between researchers across the globe to better understand the barriers to equity in the funding, conduct and publication of research from LIC and LMIC and to identify ways in which we can overcome them together.

Cancer Therapy-related Hepatic Injury in Children: Imaging Review from the Pediatric LI-RADS Working Group.

The liver is the primary organ for the metabolism of many chemotherapeutic agents. Treatment-induced liver injury is common in children undergoing cancer therapy. Hepatic injury occurs due to various mechanisms, including biochemical cytotoxicity, hepatic vascular injury, radiation-induced cytotoxicity, and direct hepatic injury through minimally invasive and invasive surgical treatments. Treatment-induced liver injury can be seen contemporaneous with therapy and months to years after therapy is complete. Patients can develop a combination of hepatic injuries manifesting during and after treatment. Acute toxic effects of cancer therapy in children include hepatitis, steatosis, steatohepatitis, cholestasis, hemosiderosis, and vascular injury. Longer-term effects of cancer therapy include hepatic fibrosis, chronic liver failure, and development of focal liver lesions. Quantitative imaging techniques can provide useful metrics for disease diagnosis and monitoring, especially in treatment-related diffuse liver injury such as hepatic steatosis and steatohepatitis, hepatic iron deposition, and hepatic fibrosis. Focal liver lesions, including those developing as a result of treatment-related vascular injury such as focal nodular hyperplasia-like lesions and hepatic perfusion anomalies, as well as hepatic infections occurring as a consequence of immune suppression, can be anxiety provoking and confused with recurrent malignancy or hepatic metastases, although there often are imaging features that help elucidate the correct diagnosis. Radiologic evaluation, in conjunction with clinical and biochemical screening, is integral to diagnosing and monitoring hepatic complications of cancer therapy in pediatric patients during therapy and after therapy completion for long-term surveillance. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material See the invited commentary by Ferraciolli and Gee in this issue.

Imaging of pediatric liver tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

Primary hepatic malignancies are relatively rare in the pediatric population, accounting for approximately 1%-2% of all pediatric tumors. Hepatoblastoma and hepatocellular carcinoma are the most common primary liver malignancies in children under the age of 5 years and over the age of 10 years, respectively. This paper provides consensus-based imaging recommendations for evaluation of patients with primary hepatic malignancies at diagnosis and follow-up during and after therapy.

Imaging of pediatric renal tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper focused on Wilms tumor and nephrogenic rests.

Malignant renal tumors account for approximately 6% of pediatric malignancies, with Wilms tumor (WT) representing approximately 90% of pediatric renal tumors. This paper provides consensus-based imaging guidelines for the initial evaluation of a child with suspected WT and follow-up during and after therapy co-developed by the Children's Oncology Group (COG) Diagnostic Imaging and Society for Pediatric Radiology (SPR) oncology committees. The guidelines for Wilms Tumor Imaging in the Society of International Pediatric Oncology (SIOP) are briefly discussed to highlight some of the differences in imaging approach.

Similarities and controversies in imaging of pediatric renal tumors: A SIOP-RTSG and COG collaboration.

Malignant renal tumors are rare in children, and Wilms tumors (WTs) are the most common subtype. Imaging plays an essential role in the diagnosis, staging, and follow-up of these patients. Initial workup for staging is mainly performed by cross-sectional imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI). Imaging approach within the two core international groups, the Children's Oncology Group (COG, North America) and the International Society of Pediatric Oncology - Renal Tumor Study Group (SIOP-RTSG, Europe), differs. Whereas abdominal ultrasound (US) is used for the initial diagnosis of a suspected pediatric renal tumor globally, COG protocols support the use of CT or MRI for locoregional staging, contrary to the preference for MRI over CT for abdominopelvic evaluation within the SIOP-RTSG. The purpose of this manuscript is to summarize current imaging approaches, highlighting differences and similarities within these core international groups, while focusing on future innovative efforts and collaboration within the HARMONICA initiative.

Optimizing Imaging of Pediatric Liver Lesions: Guidelines from the Pediatric LI-RADS Working Group.

A differential diagnosis based on a patient's age, clinical presentation, and serum α-fetoprotein level will help guide the initial imaging workup in children with a liver lesion. Children vary significantly in size, the ability to stay still, and the ability to breath hold for imaging examinations. Choosing and tailoring imaging techniques and protocols for each indication and age group is important for optimal care with minimal invasiveness. The need for sedation or anesthesia can be obviated by using techniques like feed and bundle, distraction, contrast-enhanced US, and motion-insensitive sequences for MRI. US is often the first imaging modality used in children with a suspected abdominal mass. Once a hepatic lesion is confirmed, multiphasic contrast-enhanced MRI is recommended for most lesions as the next imaging modality allowing full characterization of the lesion and assessment of the liver parenchyma. Contrast-enhanced CT can also be performed for assessment of pediatric focal liver lesions, especially in patients who have a contraindication to MRI. Contrast-enhanced US has shown promise to decrease the need for MRI or CT in some lesions such as hemangioma and focal nodular hyperplasia. Children with a history of malignancy can develop multiple types of hepatic lesions at various stages, including infections during an immunocompromised state, manifesting as focal liver lesions. Based on available limited data in the literature and the collective experiences of the Liver Imaging and Reporting Data System Pediatric Working Group, the authors provide guidelines for the imaging workup of pediatric focal liver lesions with an indication- and age-based approach and discuss the selection and performance of various imaging techniques and modalities. ©RSNA, 2022 See the invited commentary by Chojniak and Boaventura in this issue.

Pediatric Hepatic Cystic Lesions: Differential Diagnosis and Multimodality Imaging Approach.

When a pediatric hepatic cystic lesion is identified at imaging, the differential diagnosis may be broad, including developmental, infectious, neoplastic, and posttraumatic or iatrogenic causes. The location of a cystic lesion and its number, size, composition, and relationship to the biliary system are features that help in narrowing the differential diagnosis. An incidentally detected simple hepatic cyst is the most commonly encountered. Ciliated foregut cysts are typically located in hepatic segment IVa. The presence of multiple cysts should raise suspicion for fibropolycystic liver disease, a group of related lesions-including biliary hamartoma and choledochal cyst-caused by abnormal embryologic development of the ductal plate. Communication of the cystic lesion with the biliary tree can confirm the diagnosis of choledochal cyst. In a neonate with jaundice, a cystic lesion at the porta hepatis should raise suspicion for choledochal cyst versus cystic biliary atresia. Hepatic abscess can appear cystlike, though typically with internal contents. In an immunocompromised child, multiple cystlike lesions should raise concern for fungal microabscesses. A complex cystic mass in a young child should raise suspicion for mesenchymal hamartoma, which can evolve into undifferentiated embryonal sarcoma if untreated. Hepatic hematoma and biloma can appear cystlike in children with a history of trauma or recent intervention. In neonates with an umbilical vein catheter (UVC), an intrahepatic cyst along the course of the UVC should raise concern for infusate extravasation. Familiarity with imaging findings and clinical features is essential for achieving accurate diagnosis of pediatric hepatic cystic lesions, which in turn can guide appropriate clinical management. Online supplemental material is available for this article. ©RSNA, 2022.