Imaging features of adrenal gland masses in the pediatric population

International consensus statement on the diagnosis and management of phaeochromocytoma and paraganglioma in children and adolescents

Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumours that arise not only in adulthood but also in childhood and adolescence. Up to 70-80% of childhood PPGL are hereditary, accounting for a higher incidence of metastatic and/or multifocal PPGL in paediatric patients than in adult patients. Key differences in the tumour biology and management, together with rare disease incidence and therapeutic challenges in paediatric compared with adult patients, mandate close expert cross-disciplinary teamwork. Teams should ideally include adult and paediatric endocrinologists, oncologists, cardiologists, surgeons, geneticists, pathologists, radiologists, clinical psychologists and nuclear medicine physicians. Provision of an international Consensus Statement should improve care and outcomes for children and adolescents with these tumours.

Prevention and management of hypertensive crises in children with pheochromocytoma and paraganglioma

Hypertensive crises in pediatric patients are rare conditions. However, determining their precise prevalence is more challenging than in adults due to the heterogeneity in the definition itself. These crises frequently occur without a prior diagnosis of hypertension and may indicate an underlying cause of secondary hypertension, including pheochromocytoma/paraganglioma (PPGL). The mechanisms of hypertensive crises in the pediatric population with PPGL are directly related to different types of catecholamine excess. Noradrenergic tumors typically present with sustained hypertension due to their predominant action on α1-adrenoceptors in the vasculature. Conversely, adrenergic tumors, through epinephrine binding to β2-adrenoceptors in addition to stimulation of α1- and α2-adrenoceptors, more frequently cause paroxysmal hypertension. Furthermore, the biochemical phenotype also reflects the tumor localization and the presence of a genetic mutation. Recent evidence suggests that more than 80% of PPGL in pediatric cases have a hereditary background. PPGL susceptibility mutations are categorized into three clusters; mutations in cluster 1 are more frequently associated with a noradrenergic phenotype, whereas those in cluster 2 are associated with an adrenergic phenotype. Consequently, the treatment of hypertensive crises in pediatric patients with PPGL, reflecting the underlying pathophysiology, requires first-line therapy with alpha-blockers, potentially in combination with beta-blockers only in the case of tachyarrhythmia after adequate alpha-blockade. The route of administration for treatment depends on the context, such as intraoperative or pre-surgical settings, and whether it presents as a hypertensive emergency (elevated blood pressure with acute target organ damage), where intravenous administration of antihypertensive drugs is mandatory. Conversely, in cases of hypertensive urgency, if children can tolerate oral therapy, intravenous administration may initially be avoided. However, managing these cases is complex and requires careful consideration of the selection and timing of therapy administration, particularly in pediatric patients. Therefore, facing these conditions in tertiary care centers through interdisciplinary collaboration is advisable to optimize therapeutic outcomes.

A retrospective analysis of the clinical characteristics of 207 hospitalized children with adrenal masses

Objective

The detection rates of adrenal masses (AMs) have recently increased. The present study aimed to examine the clinical characteristics of these adrenal masses for guiding the clinical diagnosis and treatment among hospitalized children.

Methods

The clinical data of AM cases admitted to our hospital from January 2014 to March 2023 were collected and analyzed retrospectively. The data included composition, sex, age, initial presentation, size and site of mass, functional tumor, intervention or surgery, pathological or clinical diagnosis, and imaging data.

Results

A total of 207 hospitalized children were included. Among them, adrenal hematoma was the most common finding (53.6%), followed by adrenal neuroblastoma (36.2%). Most masses were larger-sized (51.2%) and non-functional (94.7%). We found that adrenal hematoma commonly occurred in a neonate or child with abdominal trauma. Most adrenal hematoma cases were found in male patients (63.1%), on the right side (71.2%), and with sizes <4 cm (73.9%). Adrenal neuroblastoma was commonly detected in male patients (56.0%), on the right side (66.7%), and with sizes ≥4 cm (85.3%). Moreover, the metastases were frequently explored at the time of diagnosis. In addition, there was no significant difference between ultrasound and computed tomography (CT) scans under suspicion of hematoma (P > 0.05). However, CT showed a priority over ultrasound in the diagnosis of neuroblastoma (P < 0.05).

Conclusion

Most masses were non-functional and benign. Of these, adrenal hematoma was the most common type of pediatric AM, followed by adrenal neuroblastoma. They were both commonly found in male patients and on the right side. Neuroblastoma revealed a larger tumor size. Compared to cases of adrenal hematoma, cases of adrenal neuroblastoma required CT scans for further assessment.

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

Adrenal tumors other than neuroblastoma are uncommon in children. The most frequently encountered are adrenocortical carcinoma and pheochromocytoma. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary adrenal malignancy other than neuroblastoma at diagnosis and during follow-up.

Clinical utility of nuclear imaging in the evaluation of pediatric adrenal neoplasms

Adrenal neoplasms rarely occur in children. They can be diagnosed in the presence of endocrine, metabolic or neurological problems, an abdominal mass, more rarely an adrenal incidentaloma, or in the context of an adrenal mass discovered in the evaluation of childhood cancer including hematologic malignancy. According to standard medical practice, pediatric malignancies are almost always evaluated by ¹⁸F-fluorodeoxyglucose positron emission tomography with computed tomography ([¹⁸F]FDG PET/CT). Nuclear imaging using specific radiotracers is also an important tool for diagnosing and staging neuroblastoma, pheochromocytoma, hormone hypersecretion, or indeterminate adrenal masses. The Hippocratic oath "primum non nocere" encourages limitation of radiation in children per the ALARA concept (as low as reasonably achievable) but should not lead to the under-use of nuclear imaging because of the potential risk of inaccurate diagnosis or underestimation of the extent of disease. As in adults, nuclear imaging in children should be performed in conjunction with hormone evaluation and morphological imaging.

Radiomics in Cross-Sectional Adrenal Imaging: A Systematic Review and Quality Assessment Study

In this study, we aimed to systematically review the current literature on radiomics applied to cross-sectional adrenal imaging and assess its methodological quality. Scopus, PubMed and Web of Science were searched to identify original research articles investigating radiomics applications on cross-sectional adrenal imaging (search end date February 2021). For qualitative synthesis, details regarding study design, aim, sample size and imaging modality were recorded as well as those regarding the radiomics pipeline (e.g., segmentation and feature extraction strategy). The methodological quality of each study was evaluated using the radiomics quality score (RQS). After duplicate removal and selection criteria application, 25 full-text articles were included and evaluated. All were retrospective studies, mostly based on CT images (17/25, 68%), with manual (19/25, 76%) and two-dimensional segmentation (13/25, 52%) being preferred. Machine learning was paired to radiomics in about half of the studies (12/25, 48%). The median total and percentage RQS scores were 2 (interquartile range, IQR = −5–8) and 6% (IQR = 0–22%), respectively. The highest and lowest scores registered were 12/36 (33%) and −5/36 (0%). The most critical issues were the absence of proper feature selection, the lack of appropriate model validation and poor data openness. The methodological quality of radiomics studies on adrenal cross-sectional imaging is heterogeneous and lower than desirable. Efforts toward building higher quality evidence are essential to facilitate the future translation into clinical practice.

Adrenocortical Tumors and Pheochromocytoma/Paraganglioma Initially Mistaken as Neuroblastoma-Experiences From the GPOH-MET Registry

In children and adolescents, neuroblastoma (NBL), pheochromocytoma (PCC), and adrenocortical tumors (ACT) can arise from the adrenal gland. It may be difficult to distinguish between these three entities including associated extra-adrenal tumors (paraganglioma, PGL). Precise discrimination, however, is of crucial importance for management. Biopsy in ACT or PCC is potentially harmful and should be avoided whenever possible. We herein report data on 10 children and adolescents with ACT and five with PCC/PGL, previously mistaken as NBL. Two patients with adrenocortical carcinoma died due to disease progression. Two (2/9, missing data in one patient) patients with a final diagnosis of ACT clearly presented with obvious clinical signs and symptoms of steroid hormone excess, while seven patients did not. Blood analyses indicated increased levels of steroid hormones in one additional patient; however, urinary steroid metabolome analysis was not performed in any patient. Two (2/10) patients underwent tumor biopsy, and in two others tumor rupture occurred intraoperatively. In 6/10 patients, ACT diagnosis was only established by a reference pediatric pathology laboratory. Four (4/5) patients with a final diagnosis of PCC/PGL presented with clinical signs and symptoms of catecholamine excess. Urine tests indicated possible catecholamine excess in two patients, while no testing was carried out in three patients. Measurements of plasma metanephrines were not performed in any patient. None of the five patients with PCC/PGL received adrenergic blockers before surgery. In four patients, PCC/PGL diagnosis was established by a local pathologist, and in one patient diagnosis was revised to PGL by a pediatric reference pathologist. Genetic testing, performed in three out of five patients with PCC/PGL, indicated pathogenic variants of PCC/PGL susceptibility genes. The differential diagnosis of adrenal neoplasias and associated extra-adrenal tumors in children and adolescents may be challenging, necessitating interdisciplinary and multidisciplinary efforts. In ambiguous and/or hormonally inactive cases through comprehensive biochemical testing, microscopical complete tumor resection by an experienced surgeon is vital to preventing poor outcome in children and adolescents with ACT and/or PCC/PGL. Finally, specimens need to be assessed by an experienced pediatric pathologist to establish diagnosis.

Biochemical Diagnosis of Catecholamine-Producing Tumors of Childhood: Neuroblastoma, Pheochromocytoma and Paraganglioma

Catecholamine-producing tumors of childhood include most notably neuroblastoma, but also pheochromocytoma and paraganglioma (PPGL). Diagnosis of the former depends largely on biopsy-dependent histopathology, but this is contraindicated in PPGL where diagnosis depends crucially on biochemical tests of catecholamine excess. Such tests retain some importance in neuroblastoma though continue to largely rely on measurements of homovanillic acid (HVA) and vanillylmandelic acid (VMA), which are no longer recommended for PPGL. For PPGL, urinary or plasma metanephrines are the recommended most accurate tests. Addition of methoxytyramine to the plasma panel is particularly useful to identify dopamine-producing tumors and combined with normetanephrine also shows superior diagnostic performance over HVA and VMA for neuroblastoma. While use of metanephrines and methoxytyramine for diagnosis of PPGL in adults is established, there are numerous pitfalls for use of these tests in children. The establishment of pediatric reference intervals is particularly difficult and complicated by dynamic changes in metabolites during childhood, especially in infants for both plasma and urinary measurements, and extending to adolescence for urinary measurements. Interpretation of test results is further complicated in children by difficulties in following recommended preanalytical precautions. Due to this, the slow growing nature of PPGL and neglected consideration of the tumors in childhood the true pediatric prevalence of PPGL is likely underappreciated. Earlier identification of disease, as facilitated by surveillance programs, may uncover the true prevalence and improve therapeutic outcomes of childhood PPGL. For neuroblastoma there remain considerable obstacles in moving from entrenched to more accurate tests of catecholamine excess.

Imaging findings of primary adrenal tumors in pediatric patients

Apart from neuroblastomas, adrenal tumors are rarely seen in children. The most common adrenal tumors are adrenocortical carcinoma and pheochromocytoma. Adrenocortical carcinoma is usually a large heterogeneous, well-marginated mass with solid/cystic areas and calcifications, with poor prognosis. Most of the pheochromocytomas are benign tumors and usually show intense contrast enhancement, the pattern of which may be diffuse, mottled, or peripheral on computed tomography and magnetic resonance imaging. The purpose of this article is to evaluate primary nonneurogenic adrenal tumors.

[Imaging of tumor predisposition syndromes]

CLINICAL ISSUE

Tumor predisposition syndromes (TPS) are a heterogeneous group of genetic cancers. About 10% of the approximately 2200 malignancies in the childhood in Germany develop due to an inherited disposition, whereby TPS may be underdiagnosed. The focus of this review is set on imaging of Li-Fraumeni syndrome, neurofibromatoses, tuberous sclerosis, overgrowth, and neuroendocrine syndromes.

STANDARD RADIOLOGICAL METHODS

In order to detect tumors at an early stage, screening at specific time intervals for each TPS are required. Ultrasonography and magnetic resonance imaging (MRI), especially whole-body MRI, are particularly important imaging modalities.

METHODOLOGICAL INNOVATIONS

Innovative MRI techniques can increase image quality and patient comfort. MRI acquisition time can be significantly reduced through optimized acceleration factors, motion robust radial sequences and joint acquisition and readout of multiple slices during excitation. Thus, shorter MRI examinations can be performed in younger children without anesthesia.

PRACTICAL RECOMMENDATION

Regular screening with ultrasound and MRI can reduce the morbidity and mortality of the patients affected with TPS.

Pancreatic stellate cells regulate branched-chain amino acid metabolism in pancreatic cancer

Background

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal malignancy: it has a 5-year survival rate of less than 9%. Although surgical resection is an effective treatment for PDAC, only a small number of patients can have their tumors surgically removed. Thus, an urgent need to find new therapeutic targets for PDAC exists. Understanding the molecular mechanism of PDAC development is essential for the treatment of this malignancy. This research aimed to study the mechanisms of pancreatic stellate cells (PSCs), which regulate branched-chain amino acid (BCAA) metabolism in PDAC.

Methods

Differentially expressed proteins were detected via nanoliquid chromatography coupled to mass spectrometry (nano-LC-MS/MS). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment methods were used to find the valine-leucine-isoleucine (BCAA) degradation pathway. The levels of BCAAs in the sera and tissues of patients with PDAC were measured by using nuclear magnetic resonance (NMR). The functions of BCAA concentrations and the effects of activated pancreatic stellate cells (aPSCs) were also evaluated by performing Cell Counting Kit-8, colony formation, and wound healing assays.

Results

A total of 1,519 proteins with significantly differential expression were discovered in PDAC and adjacent tissues by using nano-LC-MS/MS. KEGG pathway enrichment analysis identified the BCAA degradation pathway. The content of BCAA in PDAC clinical samples was up-regulated. However, the addition of different concentrations of BCAA to PDAC cell culture medium failed to promote the proliferation and migration of PDAC cells. Given that analysis based on The Cancer Genome Atlas database showed that the number of aPSCs gradually increased with the progression of PDAC, the effects of aPSCs on PDAC cells were explored. After coculture with aPSCs, PDAC cell proliferation showed a significant increase, and the proteins involved in the BCAA degradation pathway in PDAC cells had also changed.

Conclusions

aPSCs could regulate BCAA metabolism to enhance the progression of PDAC, indicating that the regulation of BCAA metabolism may serve as a new therapeutic direction for PDAC.

Adrenal Ganglioneuroma Presenting as an Incidentaloma in an Adolescent Patient

OBJECTIVE

In an adult endocrine clinic, the majority of patients referred for evaluation of an incidentally discovered adrenal mass are aged more than 30 years, for which many national and international societies have developed management guidelines. However, adrenal incidentalomas in children and young adults are uncommon. We report the case of an 18-year-old woman with an incidentally discovered right-sided adrenal mass.

METHODS

We present the adrenal tests, computed tomography, and magnetic resonance imaging results and treatment of a young woman with an adrenal mass that proved to be a ganglioneuroma.

RESULTS

A computed tomography scan showed a 2.2 × 2.6 cm right-sided adrenal mass with noncontrast Hounsfield units >10 and <50% washout. Magnetic resonance imaging was not typical of a lipid-rich adenoma. Blood and urine tests demonstrated normal secretion of cortisol, aldosterone, adrenal androgens, and catecholamines. Based on the patient's age and imaging studies, she underwent a right adrenalectomy, removing a 2.2 × 2.0 × 2.7-cm ganglioneuroma.

CONCLUSION

The differential diagnosis of an adrenal mass in children and adolescents is quite different compared with adult patients. There are no standardized guidelines for the management of adrenal masses in these younger age groups, although some authors recommend removing all adrenal masses, regardless of size or imaging characteristics, in all children aged more than 3 months. This case emphasizes how the management of adrenal masses in pediatric patients and young adults differs from guidelines published by endocrine and urologic societies.

Clinical, Genetic, and Prognostic Features of Adrenocortical Tumors in Children: A 10-Year Single-Center Experience

Background and Aims: Pediatric adrenocortical tumors (ACTs) are very rare endocrine neoplasms in childhood. In this study, we performed a retrospective analysis of children with ACT treated at our institution by examining clinical and genetic disease features, treatment strategies, and outcomes.

Methods: We retrospectively analyzed a cohort of 13 children treated at the Bambino Gesù Children's Hospital from November 2010 to March 2020.

Results: The median age at diagnosis was 17 months (range = 0–82 months). The female: male ratio was 3.3/1. Mixed symptomatology (>1 hormone abnormality) was the most common presentation (46.1%). In three cases, the tumor was detected during prenatal or perinatal echographic screening. All patients presented with localized disease at diagnosis and underwent total adrenalectomy. Six patients were identified as having malignancies according to the Wieneke scoring system, five benign, and two undetermined. Seven patients underwent mitotane adjuvant therapy for 12 months. There was metastatic disease in three patients, with no correlation with age or Wieneke score. The most common sites of metastases were the liver and lungs. Metastatic patients were treated with surgery (n = 2), mitotane (n = 1), chemotherapy (n = 2) associated with anti-EGFR (n = 1), or immunotherapy with anti-PD1 (pembrolizumab) (n = 1); two patients achieved complete disease remission. Overall 2- and 5-year survival rates were 100%, with a median follow-up of 5 years (range = 2–9.5 years). Two- and 5-year disease free survival was 76.9 and 84.6%, respectively (95% confidence interval = −66.78–114.76 months). All patients are alive, 12 without disease, and one with stable disease. Genetic analyses showed TP53 germline mutations in six of eight patients analyzed (five inherited, one de novo). One patient had Beckwith–Wiedemann syndrome, with mosaic paternal uniparental disomy of chromosome 11, in both neoplastic and healthy adrenal tissue.

Conclusion: We report the cases of 13 patients treated for ACT, including 12 aged <4 years at diagnosis, with a relative short time from symptoms onset. Our cohort experienced an excellent prognosis. TP53 mutation was found in 75% of tested patients (6/8) confirming the need to perform genetic tests and familial counseling in this disease.

Imaging of Adrenal-Related Endocrine Disorders

Endocrine disorders associated with adrenal pathologies can be caused by insufficient adrenal gland function or excess hormone secretion. Excess hormone secretion may result from adrenal hyperplasia or hormone-secreting (ie, functioning) adrenal masses. Based on the hormone type, functioning adrenal masses can be classified as cortisol-producing tumors, aldosterone producing tumors, and androgen-producing tumors, which originate in the adrenal cortex, as well as catecholamine-producing pheochromocytomas, which originate in the medulla. Nonfunctioning lesions can cause adrenal gland enlargement without causing hormonal imbalance. Evaluation of adrenal-related endocrine disorders requires clinical and biochemical workup associated with imaging evaluation to reach a diagnosis and guide management.