Update on pediatric cancer predisposition syndromes

Malignant Rhabdoid Tumor and Related Pediatric Tumors: Multimodality Imaging Review with Pathologic Correlation

Malignant rhabdoid tumors (MRTs) are rare but lethal solid neoplasms that overwhelmingly affect infants and young children. While the central nervous system is the most common site of occurrence, tumors can develop at other sites, including the kidneys and soft tissues throughout the body. The anatomic site of involvement dictates tumor nomenclature and nosology. While the clinical and imaging manifestations of MRTs and other more common entities may overlap, there are some site-specific distinctive imaging characteristics. Irrespective of the site of occurrence, somatic and germline mutations in SMARCB1, and rarely in SMARCA4, underlie the entire spectrum of rhabdoid tumors. MRTs have a simple and remarkably stable genome but can demonstrate considerable molecular and biologic heterogeneity. Related neoplasms encompass an expanding category of phenotypically dissimilar (nonrhabdoid tumors driven by SMARC-related alterations) entities. US, CT, MRI, and fluorodeoxyglucose PET/CT or PET/MRI facilitate diagnosis, initial staging, and follow-up, thus informing therapeutic decision making. Multifocal synchronous or metachronous rhabdoid tumors occur predominantly in the context of underlying rhabdoid tumor predisposition syndromes (RTPSs). These autosomal dominant disorders are driven in most cases by pathogenic variants in SMARCB1 (RTPS type 1) and rarely by pathogenic variants in SMARCA4 (RTPS type 2). Genetic testing and counseling are imperative in RTPS. Guidelines for imaging surveillance in cases of RTPS are based on age at diagnosis. ©RSNA, 2024 Supplemental material is available for this article.

Long-term second primary cancer risk in adolescent and young adult (15-39 years) cancer survivors: a population-based study in the Netherlands between 1989 and 2018

BACKGROUND

Few studies have comprehensively investigated the long-term second cancer risk among adolescent and young adult (AYA, aged 15-39 years) cancer survivors. This study investigated the long-term second cancer risk by including the full range of first and second cancer combinations with at least 10 observations in the Netherlands between 1989 and 2018.

MATERIALS AND METHODS

First and second primary cancer data of all 6-month AYA cancer survivors were obtained from the nationwide population-based Netherlands Cancer Registry. Excess cancer risk compared to the general population was assessed with standardized incidence ratio (SIR) and absolute excess risk (AER) statistics up to 25 years after diagnosis. Cumulative incidences were estimated, using death as a competing risk factor. Analyses were carried out with and without applying multiple cancer rules.

RESULTS

The cohort included 99 502 AYA cancer survivors. Male survivors had a 2-fold higher risk of developing any cancer compared to the general population, whereas this was around 1.3-fold in females. AERs were 17.5 and 10.1 per 10 000 person-years for males and females. The long-term excess risk of cancer was significantly higher for most first and second primary cancer combinations, but comparable and lower risk estimates were also observed. Application of the multiple cancer rules resulted in a noticeable risk underestimation in melanoma, testicular, and breast cancer survivors. Risk outcomes remained similar in most cases otherwise. The cumulative incidence of second cancer overall increased over time up to 8.9% in males and 10.3% in females at 25 years' follow-up. Highest long-term cumulative incidences were observed among lymphoma survivors (13.3% males and 18.9% females).

CONCLUSIONS

AYA cancer survivors have a higher cancer risk compared to the general population for most cancers up to 25 years after their initial cancer diagnosis. Additional studies that investigate risk factors for the specific cancer type combinations are needed to develop personalized follow-up strategies.

Pediatric, adolescent, and young adult breast and reproductive tumors

Tumors of the breast and reproductive organs that occur in children, adolescents, and young adults (AYA) have different biological features and can present special challenges. Although prognosis for these tumors is generally favorable, the long-term effects of treatment can be debilitating. Treatments are often multimodal and may include surgery as well as chemotherapy and/or radiation, which can cause considerable distress and anxiety related to loss of femininity or masculinity, concern over future fertility, or sexual dysfunction. Thus, tumors of the reproductive organs in pediatric/AYA patients require special consideration of the treatment effects beyond the intended oncologic outcome. Multidisciplinary teams should be involved in their care and address issues of fertility, sexual dysfunction, and psychosexual concerns before treatment begins. This review addresses histology, risk factors, prognosis, staging and treatment of gynecologic, breast and testicular cancers in pediatric and AYA patients.

Sensitivity and Specificity of Whole-body MRI for the Detection of Pediatric Malignancy

Children with cancer often present with general and nonspecific symptoms leading to initial diagnostic workup inclusive of clinical imaging. Various sequences of magnetic resonance imaging (MRI) are becoming more available for diagnostic imaging. However, there is currently a dearth of literature quantifying the sensitivity and specificity of whole-body MRI in identifying pediatric malignancy. In this study, a retrospective analysis was performed of pediatric whole-body MRI inclusive of short tau inversion recovery sequence conducted at an academic pediatric medical center from 2013 to 2018. Kappa statistics were used to evaluate the diagnostic agreement between MRI results and the gold standard diagnostic study of the respective final diagnosis. Sensitivity, specificity, false-positive, and false-negative estimates were provided with joint 90% confidence regions. One hundred forty-two patients received a whole-body MRI during the study period. The sensitivity of whole-body MRI in detecting malignancy was found to be 93.8% with a specificity of 93.4%. The positive and negative predictive values were determined to be 65.2% and 99.1%, respectively. Our findings suggest that whole-body MRI may be of value as an initial diagnostic tool for pediatric malignancy. Larger multicenter collaboration will be needed to further support these data.

Contribution of Inherited Variants to Hereditary Cancer Syndrome Predisposition

Cancer is a clonal disease that develops as a result of the changes on the genetic material by various factors in micro/macro environment. It has a multi-step development process. In some cancer types, genetic factors allow this multi-step process to proceed easily. These cancer types are also called hereditary cancer syndromes. Targeted gene panels are important diagnostic methods in hereditary cancer syndromes to detect the causative variants associated with these hereditary cancer syndromes. We reviewed the data of 94 patients who applied to Ankara City Hospital Genetic Diseases Evaluation Center from March 2019 to July 2021. Qiagen familial cancer susceptibility gene panel kit was used for next generation sequencing to detect the single nucleotide variants for the targeted genes. Sixty-one genes which are associated with increased cancer risk or well characterized hereditary cancer syndromes were included to this panel. Twenty five patients (27%), including 8 males and 17 females, had pathogenic/likely pathogenic variants in 13 of the 61 genes analyzed. Forty patients (43%) had variants which were assessed as variant of unknown significant. In our study, targeted multi-gene panel was diagnostic in nearly one third of the patients with personal/familial cancer syndromes. Molecular diagnosis in familial cancer syndromes is important in terms of predictive diagnosis and family screening, as well as patient follow-up and early prophylactic surgery. The predisposition for hereditary cancer syndromes can be determined according to pre-test evaluation, figuring out the inheritance type with pedigree analysis, cancer type and the genetic analysis for appropriate susceptibility genes.

Defining the Spectrum, Treatment and Outcome of Patients With Genetically Confirmed Gorlin Syndrome From the HIT-MED Cohort

Gorlin syndrome is a genetic condition associated with the occurrence of SHH activated medulloblastoma, basal cell carcinoma, macrocephaly and other congenital anomalies. It is caused by heterozygous pathogenic variants in PTCH1 or SUFU. In this study we included 16 patients from the HIT2000, HIT2000interim, I-HIT-MED, observation registry and older registries such as HIT-SKK87, HIT-SKK92 (1987 – 2020) with genetically confirmed Gorlin syndrome, harboring 10 PTCH1 and 6 SUFU mutations. Nine patients presented with desmoplastic medulloblastomas (DMB), 6 with medulloblastomas with extensive nodularity (MBEN) and one patient with classic medulloblastoma (CMB); all tumors affected the cerebellum, vermis or the fourth ventricle. SHH activation was present in all investigated tumors (14/16); DNA methylation analysis (when available) classified 3 tumors as iSHH-I and 4 tumors as iSHH-II. Age at diagnosis ranged from 0.65 to 3.41 years. All but one patient received chemotherapy according to the HIT-SKK protocol. Ten patients were in complete remission after completion of primary therapy; four subsequently presented with PD. No patient received radiotherapy during initial treatment. Five patients acquired additional neoplasms, namely basal cell carcinomas, odontogenic tumors, ovarian fibromas and meningioma. Developmental delay was documented in 5/16 patients. Overall survival (OS) and progression-free survival (PFS) between patients with PTCH1 or SUFU mutations did not differ statistically (10y-OS 90% vs. 100%, p=0.414; 5y-PFS 88.9% ± 10.5% vs. 41.7% ± 22.2%, p=0.139). Comparing the Gorlin patients to all young, SHH activated MBs in the registries (10y-OS 93.3% ± 6.4% vs. 92.5% ± 3.3%, p=0.738; 10y-PFS 64.9%+-16.7% vs. 83.8%+-4.5%, p=0.228) as well as comparing Gorlin M0 SKK-treated patients to all young, SHH activated, M0, SKK-treated MBs in the HIT-MED database did not reveal significantly different clinical outcomes (10y-OS 88.9% ± 10.5% vs. 88% ± 4%, p=0.812; 5y-PFS 87.5% ± 11.7% vs. 77.7% ± 5.1%, p=0.746). Gorlin syndrome should be considered in young children with SHH activated medulloblastoma, especially DMB and MBEN but cannot be ruled out for CMB. Survival did not differ to patients with SHH-activated medulloblastoma with unknown germline status or between PTCH1 and SUFU mutated patients. Additional neoplasms, especially basal cell carcinomas, need to be expected and screened for. Genetic counselling should be provided for families with young medulloblastoma patients with SHH activation.

The relationship among primary anatomic subsite and risk and distribution of second malignant neoplasms in patients with stage I/II diffuse large B-cell lymphoma: An analysis of the surveillance, epidemiology, and end results database

BACKGROUND

Recent studies have reported that diffuse large B-cell lymphoma (DLBCL) involving different primary extranodal sites have distinct clinicopathological characteristics and prognosis. However, the risk of secondary malignant neoplasms (SMNs) in DLBCL survivors with different primary extranodal sites are unknown.

METHODS

A total of 40,714 patients diagnosed with stage I/II DLBCL were included from the Surveillance, Epidemiology, and End Results (SEER) database from 1983 to 2015.The standardized incidence ratio (SIR) and absolute excess risk (AER) were used to assess the risk of SMNs.

RESULTS

The results show that the risk of SMN was significantly higher in extranodal DLBCL than in the US general population (SIR, 1.18; 95% CI, 1.11-1.26), and the risk of developing SMN remains significantly elevated with increased latency. Moreover, there were multiple site-specific risk patterns. There was a 22%, 44%, 66%, 123% and 151% increased risk of SMN 10 years after primary gastrointestinal tract, head/neck, skeletal, lung and liver/pancreas DLBCL diagnosis, respectively. There was a significant decrease risk of SMN with increasing age at diagnosis for primary gastrointestinal tract and skeletal DLBCL. In addition, DLBCL patients with primary sites in the gastrointestinal tract, thyroid and liver/pancreas had the highest incidences of secondary stomach cancer, second thyroid cancer, and second hepatobiliary cancer, respectively, which indicated that the initial site of DLBCL may predict the type of SMN.

CONCLUSIONS

The strategies for cancer surveillance after extranodal DLBCL diagnosis may need to be individualized according to the subsite of extranodal DLBCL.

Hotspot Mutations in DICER1 Causing GLOW Syndrome-Associated Macrocephaly via Modulation of Specific microRNA Populations Result in the Activation of PI3K/ATK/mTOR Signaling

BACKGROUND

We have previously described mosaic mutations in the RNase IIIb domain of DICER1that display global developmental delays, lung cysts, somatic overgrowth, macrocephaly and Wilms tumor. This constellation of phenotypes was classified as GLOW syndrome. Due to the phenotypic overlap between GLOW and syndromes caused by mutations in the PI3K/AKT/mTOR pathway, we hypothesized that alterations in miRNA regulation of this pathway cause its specific constellation of phenotypes.

OBJECTIVE

To test the hypothesis that DICER1 "hot spot" mutations associated with GLOW syndrome activate PI3K/AKT/mTOR signaling.

METHODS

We developed HEK293T cells with loss of exon 25 in DICER1, a genetic modification that is synonymous with the "hot spot" RNAseIIIb mutations that cause GLOW syndrome. We assayed the cells for activation of the PI3K/AKT/mTOR signaling pathway.

RESULTS

We observed activation of the PI3K/AKT/mTOR pathway as demonstrated by increased pS6Kinase, p4EBP1 and pTSC2 levels. Additionally, these cells demonstrate a striking cellular phenotype, with the ability to form spheres when the serum is removed from their growth medium. The cells in these spheres are Oct4 and Sox2 positive and exhibit the property of reversion with the addition of serum. We queried miRNA expression data and identified a population of miRNAs that increase due to these mutations and target negative regulators of the PI3K/AKT/mTOR pathway.

CONCLUSION

This work identifies the delicate and essential role for miRNA control of the PI3K/AKT/mTOR pathway. We conclude that the phenotypes observed in the GLOW syndrome are the result of PI3K/AKT/mTOR activation.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY GUIDELINES FOR MANAGEMENT OF GROWTH HORMONE DEFICIENCY IN ADULTS AND PATIENTS TRANSITIONING FROM PEDIATRIC TO ADULT CARE

Objective: The development of these guidelines is sponsored by the American Association of Clinical Endocrinologists (AACE) Board of Directors and American College of Endocrinology (ACE) Board of Trustees and adheres with published AACE protocols for the standardized production of clinical practice guidelines (CPG). Methods: Recommendations are based on diligent reviews of clinical evidence with transparent incorporation of subjective factors, according to established AACE/ACE guidelines for guidelines protocols. Results: The Executive Summary of this 2019 updated guideline contains 58 numbered recommendations: 12 are Grade A (21%), 19 are Grade B (33%), 21 are Grade C (36%), and 6 are Grade D (10%). These detailed, evidence-based recommendations allow for nuance-based clinical decision-making that addresses multiple aspects of real-world care of patients. The evidence base presented in the subsequent Appendix provides relevant supporting information for the Executive Summary recommendations. This update contains 357 citations of which 51 (14%) are evidence level (EL) 1 (strong), 168 (47%) are EL 2 (intermediate), 61 (17%) are EL 3 (weak), and 77 (22%) are EL 4 (no clinical evidence). Conclusion: This CPG is a practical tool that practicing endocrinologists and regulatory bodies can refer to regarding the identification, diagnosis, and treatment of adults and patients transitioning from pediatric to adult-care services with growth hormone deficiency (GHD). It provides guidelines on assessment, screening, diagnostic testing, and treatment recommendations for a range of individuals with various causes of adult GHD. The recommendations emphasize the importance of considering testing patients with a reasonable level of clinical suspicion of GHD using appropriate growth hormone (GH) cut-points for various GH-stimulation tests to accurately diagnose adult GHD, and to exercise caution interpreting serum GH and insulin-like growth factor-1 (IGF-1) levels, as various GH and IGF-1 assays are used to support treatment decisions. The intention to treat often requires sound clinical judgment and careful assessment of the benefits and risks specific to each individual patient. Unapproved uses of GH, long-term safety, and the current status of long-acting GH preparations are also discussed in this document. LAY ABSTRACT This updated guideline provides evidence-based recommendations regarding the identification, screening, assessment, diagnosis, and treatment for a range of individuals with various causes of adult growth-hormone deficiency (GHD) and patients with childhood-onset GHD transitioning to adult care. The update summarizes the most current knowledge about the accuracy of available GH-stimulation tests, safety of recombinant human GH (rhGH) replacement, unapproved uses of rhGH related to sports and aging, and new developments such as long-acting GH preparations that use a variety of technologies to prolong GH action. Recommendations offer a framework for physicians to manage patients with GHD effectively during transition to adult care and adulthood. Establishing a correct diagnosis is essential before consideration of replacement therapy with rhGH. Since the diagnosis of GHD in adults can be challenging, GH-stimulation tests are recommended based on individual patient circumstances and use of appropriate GH cut-points. Available GH-stimulation tests are discussed regarding variability, accuracy, reproducibility, safety, and contraindications, among other factors. The regimen for starting and maintaining rhGH treatment now uses individualized dose adjustments, which has improved effectiveness and reduced reported side effects, dependent on age, gender, body mass index, and various other individual characteristics. With careful dosing of rhGH replacement, many features of adult GHD are reversible and side effects of therapy can be minimized. Scientific studies have consistently shown rhGH therapy to be beneficial for adults with GHD, including improvements in body composition and quality of life, and have demonstrated the safety of short- and long-term rhGH replacement. Abbreviations: AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; AHSG = alpha-2-HS-glycoprotein; AO-GHD = adult-onset growth hormone deficiency; ARG = arginine; BEL = best evidence level; BMD = bone mineral density; BMI = body mass index; CI = confidence interval; CO-GHD = childhood-onset growth hormone deficiency; CPG = clinical practice guideline; CRP = C-reactive protein; DM = diabetes mellitus; DXA = dual-energy X-ray absorptiometry; EL = evidence level; FDA = Food and Drug Administration; FD-GST = fixed-dose glucagon stimulation test; GeNeSIS = Genetics and Neuroendocrinology of Short Stature International Study; GH = growth hormone; GHD = growth hormone deficiency; GHRH = growth hormone-releasing hormone; GST = glucagon stimulation test; HDL = high-density lipoprotein; HypoCCS = Hypopituitary Control and Complications Study; IGF-1 = insulin-like growth factor-1; IGFBP = insulin-like growth factor-binding protein; IGHD = isolated growth hormone deficiency; ITT = insulin tolerance test; KIMS = Kabi International Metabolic Surveillance; LAGH = long-acting growth hormone; LDL = low-density lipoprotein; LIF = leukemia inhibitory factor; MPHD = multiple pituitary hormone deficiencies; MRI = magnetic resonance imaging; P-III-NP = procollagen type-III amino-terminal pro-peptide; PHD = pituitary hormone deficiencies; QoL = quality of life; rhGH = recombinant human growth hormone; ROC = receiver operating characteristic; RR = relative risk; SAH = subarachnoid hemorrhage; SDS = standard deviation score; SIR = standardized incidence ratio; SN = secondary neoplasms; T3 = triiodothyronine; TBI = traumatic brain injury; VDBP = vitamin D-binding protein; WADA = World Anti-Doping Agency; WB-GST = weight-based glucagon stimulation test.

Application of genome analysis strategies in the clinical testing for pediatric diseases

Next‐generation sequencing (NGS) is being used in clinical testing. Government authorities in both China and the United States are overseeing the clinical application of NGS instruments and reagents. In addition, the US Association for Molecular Pathology and the College of American Pathologists have jointly released a guidance to standardize the analysis and interpretation of NGS data involved in clinical testing. At present, the analysis strategies and pipelines for NGS data related to the clinical detection of pediatric disease are similar to those used for adult diseases. However, for rare pediatric diseases without linkage to known genetic variants, it is currently difficult to detect the relevant pathogenic genes using NGS technology. Additionally, it is challenging to identify novel pathogenic genes of familial pediatric tumors. Therefore, characterization of the pathogenic genes associated with above diseases is important for the diagnosis and treatment of rare diseases in children. This article introduces the general pipelines for NGS data analyses of diseases and elucidates data analysis strategies for the pathogenic genes of rare pediatric diseases and familial pediatric tumors.

Family history of cancer and the risk of childhood solid tumours: a Norwegian nationwide register-based cohort study

Background:

It is not clear if family history of cancer increases risk of cancer in children.

Methods:

We followed-up a total of 2 610 937 children born between 1960 and 2001 for cancer risk, and their parents and siblings. In this period, 2477 primary childhood solid tumours (except lymphoma) were diagnosed. The data from the Norwegian Family and Life Course Study and from the Norwegian Cancer Register were used. Classification of hereditary cancer syndromes was based on tumour histology, pedigrees and Chompret’s criteria.

Results:

An association between risk of childhood tumours and first-degree family history of early onset of solid tumours was observed for central nervous system tumours (2.3-fold), neuroblastoma (2.3-fold), retinoblastoma (6.1-fold), hepatic tumours (4.0-fold), and melanomas (8.3-fold). Elevated risk was also seen for osteosarcomas (1.5-fold) when considering first-degree family history of cancer diagnosed at any age. The risk of hepatic tumours, neuroblastomas and melanomas remained elevated even after controlling for probable hereditary cancer syndromes.

Conclusions:

The increased risk for several childhood solid site cancers among those with first-degree relatives diagnosed with solid cancer suggests that genetic or environmental factors are involved. The fact that these associations remained after controlling for hereditary cancer syndromes indicates other genetic mechanisms might be involved.

Pediatric oncologist willingness to offer germline TP53 testing in osteosarcoma

BACKGROUND

Li-Fraumeni syndrome (LFS) is a cancer predisposition syndrome caused by mutations in the tumor-suppressor gene TP53. Osteosarcoma is a sentinel cancer in LFS. Prior studies using Sanger sequencing platforms have demonstrated that 3% of individuals with osteosarcoma harbor a mutation in TP53. New data from next-generation sequencing have demonstrated that 3.8% of patients with osteosarcoma have a known pathogenic variant, and an additional 5.7% carry exonic variants of unknown significance in TP53.

METHODS

Pediatric oncologists were e-mailed an anonymous 18-question survey assessing their willingness to offer TP53 germline testing to a child with osteosarcoma with or without a family history, and they were evaluated for changes in their choices with the prior data and the new data.

RESULTS

One hundred seventy-seven pediatric oncologists (22%) responded to the survey. Respondents were more likely to offer TP53 testing to a patient with a positive family history (77.4% vs 12.4%; P < .0001). Significantly more providers responded that they would offer TP53 testing once they were provided with the new data (25.4% vs 12.4%; P = .0038). The proportion of providers who responded that they were unsure increased significantly when they were presented with the new data (25.4% vs 10.2%; P = .0002). Potential implications for other family members and the possibility that surveillance imaging would detect new malignancies at an earlier stage were important factors influencing a provider's decision to offer TP53 testing.

CONCLUSIONS

Recent data increase the proportion of providers willing to offer testing, and this suggests concern on the part of pediatric oncologists that variants of unknown significance may be disease-defining in rare cancers. Cancer 2018;124:1242-50. © 2018 American Cancer Society.

Predominance of girls with cancer in families with multiple childhood cancer cases

Background

Recent studies indicate that one of four childhood cancers can be attributed to hereditary genetic abnormalities.

Methods

The Lund Childhood Cancer Genetic study includes newly diagnosed childhood cancer patients as well as childhood cancer survivors visiting the Department of Pediatrics or the Late Effect Clinic at Skåne University Hospital, Lund, Sweden. Questionnaires regarding family history of cancer and blood samples were provided. Reported data were validated and extended by use of the Swedish Population- and Cancer Registries. Demographics in families with one case of childhood cancer (FAM1) were investigated and compared to families with multiple cases of childhood cancer (FAM > 1) as well as to childhood cancer in the general population.

Results

Forty-one out of 528 families (7.8%) had more than one case of childhood cancer. In 23 families the affected children were relatives up to a 3rd degree (4.4%). In FAM > 1, 69.2% of the children with leukemia and 60% of those with tumors in the central nervous system (CNS) had a childhood relative with matching diagnosis, both significantly higher than expected. Significantly more female than male patients were observed in FAM > 1 compared to FAM1. This female predominance was most striking in childhood leukemia (77% female) and also, yet to a lesser extent, in CNS tumors (68% female).

Conclusions

We conclude that the high proportion of children with leukemia or CNS tumors in FAM > 1 having a childhood relative with the same diagnosis suggests a hereditary background. Moreover, we report a female predominance in childhood leukemia and childhood CNS tumors in FAM > 1, which may indicate a hereditary gender-specific risk factor in these families.

Concurrent myeloid sarcoma, atypical teratoid/rhabdoid tumor, and hypereosinophilia in an infant with a germline SMARCB1 mutation

We report a 1-year-old female child presenting with hypereosinophilia who was found to have concurrent myeloid sarcoma and a central nervous system (CNS) atypical teratoid/rhabdoid tumor (AT/RT). She was later found to have a germline mutation in SMARCB1. Concurrent hematologic malignancy and CNS AT/RT have not previously been described in the context of a SMARCB1 loss-of-function germline mutation.

Ethical considerations surrounding germline next-generation sequencing of children with cancer

INTRODUCTION

The advent of next-generation sequencing (NGS) has introduced an exciting new era in biomedical research. NGS forms the foundation of current genetic testing approaches, including targeted gene panel testing, as well as more comprehensive whole-exome and whole-genome sequencing. Together, these approaches promise to provide critical insights into the understanding of health and disease. However, with NGS testing come many ethical questions and concerns, particularly when testing involves children. These concerns are especially relevant for children with cancer, where the testing of tumor and germline tissues is increasingly being incorporated into clinical care. Areas covered: In this manuscript, we explore the key ethical considerations related to conducting germline NGS testing in pediatric oncology, focusing on the four main principles of beneficence, non-maleficence, autonomy and justice. Expert commentary: The ethical issues surrounding germline NGS testing are complex and result in part from our limited understanding of the medical relevance of many of the results obtained and poor knowledge of the impacts of testing, both beneficial and detrimental, on patients and their families. In this article we discuss the risks and benefits of germline NGS testing and the arguments for and against such testing in children with cancer.

Advances in the Treatment of Pediatric Bone Sarcomas

Bone tumors make up a significant portion of noncentral nervous system solid tumor diagnoses in pediatric oncology patients. Ewing sarcoma and osteosarcoma, both with distinct clinical and pathologic features, are the two most commonly encountered bone cancers in pediatrics. Although mutations in the germline have classically been more associated with osteosarcoma, there is recent evidence germline alterations in patients with Ewing sarcoma also play a significant role in pathogenesis. Treatment advances in this patient population have lagged behind that of other pediatric malignancies, particularly targeted interventions directed at the biologic underpinnings of disease. Recent advances in biologic and genomic understanding of these two cancers has expanded the potential for therapeutic advancement and prevention. In Ewing sarcoma, directed focus on inhibition of EWSR1-FLI1 and its effectors has produced promising results. In osteosarcoma, instead of a concentrated focus on one particular change, largely due to tumor heterogeneity, a more diversified approach has been adopted including investigations of growth factors inhibitors, signaling pathway inhibitors, and immune modulation. Continuing recently made treatment advances relies on clinical trial design and enrollment. Clinical trials should include incorporation of biological findings; specifically, for Ewing sarcoma, assessment of alternative fusions and, for osteosarcoma, stratification utilizing biomarkers. Expanded cancer genomics knowledge, particularly with solid tumors, as it relates to heritability and incorporation of family history has led to early identification of patients with cancer predisposition. In these patients through application of cost-effective evidence-based screening techniques the ultimate goal of cancer prevention is becoming a realization.

Rhabdoid Tumor Predisposition Syndrome and Pleuropulmonary Blastoma Syndrome

In recent years, hereditary cancer syndromes have developed greater interest in the scientific community. Two such syndromes, rhabdoid tumor syndrome and pleuropulmonary blastoma (DICER1) syndrome, have appeared increasingly in the literature. This review will discuss these two syndromes in terms of clinical parameters, associated tumors, and genetic associations.

Syndrome-Associated Tumors by Organ System

Certain tumors suggest the possibility of a patient harboring a genetic syndrome, particularly in children. Syndrome-associated tumors of the gastrointestinal tract, genitourinary tract, gynecologic tract, heart, lungs, brain, eye, endocrine organs, and hematopoietic system will be briefly discussed.

Considering GH replacement for GH-deficient adults with a previous history of cancer: a conundrum for the clinician

Previous studies have shown that GH and IGF-I may enhance tumorigenesis, metastasis, and cell proliferation in humans and animals. Evidence supporting this notion is derived from animal model studies, epidemiological studies, experience from patients with acromegaly, molecular therapeutic manipulation of GH and IGF-I actions, and individuals with GH receptor and congenital IGF-I deficiencies. Prior exposure to radiation therapy, aging, family history of cancer, and individual susceptibility may also contribute to increase this risk. Therefore, the use of GH replacement in patients with a history of cancer raises hypothetical safety concerns for patients, caregivers, and providers. Studies of GH therapy in GH-deficient adults with hypopituitarism and childhood cancer survivors have not convincingly demonstrated an increased cancer risk. Conversely, the risk of occurrence of a second neoplasm (SN) in childhood cancer survivors may be increased, with meningiomas being the most common tumor; however, this risk appears to decline over time. In light of these findings, if GH replacement is to be considered in patients with a previous history of cancer, we propose this consideration to be based on each individual circumstance and that such therapy should only be initiated at least 2 years after cancer remission is achieved with the understanding that in some patients (particularly those with childhood cancers), GH may potentially increase the risk of SNs. In addition, close surveillance should be undertaken working closely with the patient's oncologist. More long-term data are thus needed to determine if GH replacement in GH-deficient adults with a history of cancer is associated with the development of de novo tumors and tumor recurrence.

Von Hippel-Lindau Disease: Genetics and Role of Genetic Counseling in a Multiple Neoplasia Syndrome

Von Hippel-Lindau disease (VHL) is one of the most common inherited neoplasia syndromes and is characterized by highly vascular tumors of the eyes, brain, and spine, as well as benign and malignant tumors and/or cysts of the kidneys, adrenal medullae and sympathetic paraganglia, endolymphatic sac, epididymis, and broad ligament. Since the discovery of the VHL gene in 1993, more than 900 families with VHL have been identified and examined. Genetic testing for VHL is widely available and will detect a disease-causing mutation in rate 95% to 100% of individuals who have a clinical diagnosis of VHL, making it the standard of care for diagnosis of VHL. Furthermore, genetic testing for VHL is indicated in some individuals with seemingly sporadic VHL-related tumor types, as ≤ 10% of pheochromocytoma or early-onset renal cell carcinoma and ≤ 40% of CNS hemangioblastoma harbor germline VHL mutations without a family history or additional features of VHL disease. The majority of VHL mutations are private, but there are also well-characterized founder mutations. VHL is a complex, multiorgan disease that spans the breadth of oncology subspecialties, and, as such, providers in these subspecialties should be aware of when to consider a diagnosis of VHL, when to refer a patient to a genetics specialist for consideration of gene testing, and, perhaps most importantly, how to communicate this sensitive information in an age-appropriate manner to at-risk families. This review will provide state-of-the-art information regarding the genetics of VHL and will serve as a key reference for nongenetics professionals who encounter patients with VHL.

Comparative oncology: what dogs and other species can teach us about humans with cancer

Over 1.66 million humans (approx. 500/100,000 population rate) and over 4.2 million dogs (approx. 5300/100,000 population rate) are diagnosed with cancer annually in the USA. The interdisciplinary field of comparative oncology offers a unique and strong opportunity to learn more about universal cancer risk and development through epidemiology, genetic and genomic investigations. Working across species, researchers from human and veterinary medicine can combine scientific findings to understand more quickly the origins of cancer and translate these findings to novel therapies to benefit both human and animals. This review begins with the genetic origins of canines and their advantage in cancer research. We next focus on recent findings in comparative oncology related to inherited, or genetic, risk for tumour development. We then detail the somatic, or genomic, changes within tumours and the similarities between species. The shared cancers between humans and dogs that we discuss include sarcoma (osteosarcoma, soft tissue sarcoma, histiocytic sarcoma, hemangiosarcoma), haematological malignancies (lymphoma, leukaemia), bladder cancer, intracranial neoplasms (meningioma, glioma) and melanoma. Tumour risk in other animal species is also briefly discussed. As the field of genomics advances, we predict that comparative oncology will continue to benefit both humans and the animals that live among us.

Risk-reduction surgery in pediatric surgical oncology: A perspective

OBJECTIVE

A small percentage of pediatric solid cancers arise as a result of clearly identified inherited predisposition syndromes and nongenetic lesions. Evidence supports preemptive surgery for children with genetic [multiple endocrine neoplasia type 2 (MEN2), familial adenomatous polyposis syndrome (FAP), hereditary nonpolyposis colorectal cancer (HNPCC), and hereditary diffuse gastric cancer (HDGC) and nongenetic [thyroglossal duct cysts (TGDC), congenital pulmonary airway malformations (CPAM), alimentary tract duplication cysts (ATDC), and congenital choledochal cysts (CCC)] developmental anomalies. Our aim was to explore the utility of risk reduction surgery to treat and prevent cancer in children.

METHODS

A systematic review of the available peer-reviewed literature on PubMed was performed using a PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) search strategy, where possible. Search items included "risk reduction surgery", "hereditary cancer predisposition syndrome", "multiple endocrine neoplasia type 2", "familial adenomatous polyposis", "hereditary nonpolyposis colorectal cancer", "hereditary diffuse gastric cancer", "thyroglossal duct cysts", congenital pulmonary airway malformations", "alimentary tract duplication cysts", "malignant transformation", and "guidelines".

RESULTS

We identified 67 articles that met the inclusion criteria describing the indications for prophylactic surgery in surgical oncology. For the genetic predisposition syndromes, 7 studies were related to professional endorsed guidelines, 7 were related to surgery for MEN2, 11 were related to colectomy for FAP, 6 were related to colectomy for HNPCC, and 12 related to gastrectomy for HDGC. Articles for the nongenetic lesions included 5 for techniques related to TGDC resection, 9 for surgery for CPAMs, and 10 for resection of ATDCs. Guidelines and strategies varied significantly especially related to the extent and timing of surgical intervention; the exception was for the timing of thyroidectomy in children with MEN2.

CONCLUSION

Current evidence supporting prophylactic surgery in the management of pediatric cancer predisposition syndromes and nongenetic lesions is best delineated for thyroidectomy to prevent medullary thyroid cancer in children with MEN2 (Strength of Recommendation Grade B/C). Despite the lack of pediatric specific evidence-based recommendations regarding the appropriate extent and timing for risk-reduction surgery for FAP, HNPCC, HDGC and nongenetic anomalies, our review represents an opportunity towards understanding the postgenomic development of these lesions and provides current indications and techniques for preemptive cancer prevention surgery in children.

Is Whole-Exome Sequencing an Ethically Disruptive Technology? Perspectives of Pediatric Oncologists and Parents of Pediatric Patients With Solid Tumors

BACKGROUND

It has been anticipated that physician and parents will be ill prepared or unprepared for the clinical introduction of genome sequencing, making it ethically disruptive.

PROCEDURE

As a part of the Baylor Advancing Sequencing in Childhood Cancer Care study, we conducted semistructured interviews with 16 pediatric oncologists and 40 parents of pediatric patients with cancer prior to the return of sequencing results. We elicited expectations and attitudes concerning the impact of sequencing on clinical decision making, clinical utility, and treatment expectations from both groups. Using accepted methods of qualitative research to analyze interview transcripts, we completed a thematic analysis to provide inductive insights into their views of sequencing.

RESULTS

Our major findings reveal that neither pediatric oncologists nor parents anticipate sequencing to be an ethically disruptive technology, because they expect to be prepared to integrate sequencing results into their existing approaches to learning and using new clinical information for care. Pediatric oncologists do not expect sequencing results to be more complex than other diagnostic information and plan simply to incorporate these data into their evidence-based approach to clinical practice, although they were concerned about impact on parents. For parents, there is an urgency to protect their child's health and in this context they expect genomic information to better prepare them to participate in decisions about their child's care.

CONCLUSIONS

Our data do not support the concern that introducing genome sequencing into childhood cancer care will be ethically disruptive, that is, leave physicians or parents ill prepared or unprepared to make responsible decisions about patient care.

Metabolic dysregulation in monogenic disorders and cancer - finding method in madness

Cancer is a prime example of a disease process in which carcinogenic and metabolic changes are intertwined to promote cell survival and growth. One approach to unravel this complex relationship is by studying rare, monogenic disorders caused by mutations in genes encoding metabolic enzymes or regulators. There are hundreds of these diseases, most of which manifest in childhood and are collectively termed 'inborn errors of metabolism' (IEMs). Several IEMs demonstrate the consequences of chronic, systemic loss of a particular metabolic activity that can result in malignancy. In this Opinion article, we present a conceptual categorization of IEMs associated with cancer and discuss how assessment of these rare diseases might inform us about the biological foundations of common types of cancer and opportunities for cancer diagnosis and therapy.

Risk of Neoplasia in Pediatric Patients Receiving Growth Hormone Therapy--A Report From the Pediatric Endocrine Society Drug and Therapeutics Committee

CONTEXT

GH and IGF-1 have been shown to affect tumor growth in vitro and in some animal models. This report summarizes the available evidence on whether GH therapy in childhood is associated with an increased risk of neoplasia during treatment or after treatment is completed.

EVIDENCE ACQUISITION

A PubMed search conducted through February 2014 retrieved original articles written in English addressing GH therapy and neoplasia risk. Subsequent searches were done to include additional relevant publications.

EVIDENCE SYNTHESIS

In children without prior cancer or known risk factors for developing cancer, the clinical evidence does not affirm an association between GH therapy during childhood and neoplasia. GH therapy has not been reported to increase the risk for neoplasia in this population, although most of these data are derived from postmarketing surveillance studies lacking rigorous controls. In patients who are at higher risk for developing cancer, current evidence is insufficient to conclude whether or not GH further increases cancer risk. GH treatment of pediatric cancer survivors does not appear to increase the risk of recurrence but may increase their risk for subsequent primary neoplasms.

CONCLUSIONS

In children without known risk factors for malignancy, GH therapy can be safely administered without concerns about an increased risk for neoplasia. GH use in children with medical diagnoses predisposing them to the development of malignancies should be critically analyzed on an individual basis, and if chosen, appropriate surveillance for malignancies should be undertaken. GH can be used to treat GH-deficient childhood cancer survivors who are in remission with the understanding that GH therapy may increase their risk for second neoplasms.

Germline TP53 mutations and the changing landscape of Li-Fraumeni syndrome

Since its description by Li and Fraumeni over 40 years ago, Li-Fraumeni syndrome (LFS) remains one of the most striking familial cancer predisposition syndromes. Children and adults are affected by a wide array of cancers that occur predominantly at younger ages. This review discusses LFS, describes its association with TP53, and examines the classic and evolving definitions of the syndrome. The potential implications of multigene assessments of individuals at increased cancer risk, which have already begun to identify those with very little personal or family cancer history carrying germline TP53 mutations, are considered. Newer options in the management of individuals with LFS are also discussed, highlighting the importance of further clinical trials for cancer detection, prevention, and management. Finally, we observe how the clinical criteria for TP53 mutation screening appear to be evolving as our understanding of the impact of germline TP53 mutations continues to expand.

Management of familial cancer: sequencing, surveillance and society

The clinical management of familial cancer begins with recognition of patterns of cancer occurrence suggestive of genetic susceptibility in a proband or pedigree, to enable subsequent investigation of the underlying DNA mutations. In this regard, next-generation sequencing of DNA continues to transform cancer diagnostics, by enabling screening for cancer-susceptibility genes in the context of known and emerging familial cancer syndromes. Increasingly, not only are candidate cancer genes sequenced, but also entire 'healthy' genomes are mapped in children with cancer and their family members. Although large-scale genomic analysis is considered intrinsic to the success of cancer research and discovery, a number of accompanying ethical and technical issues must be addressed before this approach can be adopted widely in personalized therapy. In this Perspectives article, we describe our views on how the emergence of new sequencing technologies and cancer surveillance strategies is altering the framework for the clinical management of hereditary cancer. Genetic counselling and disclosure issues are discussed, and strategies for approaching ethical dilemmas are proposed.

Parent decision-making around the genetic testing of children for germline TP53 mutations

BACKGROUND

Li-Fraumeni syndrome is a rare genetic cancer predisposition syndrome caused by germline TP53 mutations. Up to 20% of mutation carriers develop cancer during childhood. The benefits of TP53 mutation testing of children are a matter of debate and knowledge of parent decision-making around such testing is limited. The current study examined how parents make decisions regarding TP53 testing for their children.

METHODS

Families offered and those pursuing TP53 testing for their children were identified across the study sites. Qualitative interviews with 46 parents (39 families) were analyzed to describe decision-making styles and perceived advantages and disadvantages of testing.

RESULTS

TP53 mutation testing uptake was high (92%). Three decision-making styles emerged. Automatic decisions (44% of decisions) involved little thought and identified immediate benefit(s) in testing (100% pursued testing). Considered decisions (49%) weighed the risks and benefits but were made easily (77% pursued testing). Deliberated decisions (6%) were difficult and focused on psychosocial concerns (25% pursued testing). Perceived advantages of testing included promoting child health, satisfying a "need to know," understanding why cancer(s) occurred, suggesting family member risk, and benefiting research. Disadvantages included psychosocial risks and privacy/discrimination/insurance issues.

CONCLUSIONS

Although empirical evidence regarding the benefits and risks of TP53 testing during childhood are lacking, the majority of parents in the current study decided easily in favor of testing and perceived a range of advantages. The authors conclude that in the context of a clinical diagnosis of Li-Fraumeni syndrome, parents should continue to be offered TP53 testing for their children, counseled regarding potential risks and benefits, and supported in their decision-making process.

Impact of NGS in the medical sciences: Genetic syndromes with an increased risk of developing cancer as an example of the use of new technologies

The increased speed and decreasing cost of sequencing, along with an understanding of the clinical relevance of emerging information for patient management, has led to an explosion of potential applications in healthcare. Currently, SNP arrays and Next-Generation Sequencing (NGS) technologies are relatively new techniques used to scan genomes for gains and losses, losses of heterozygosity (LOH), SNPs, and indel variants as well as to perform complete sequencing of a panel of candidate genes, the entire exome (whole exome sequencing) or even the whole genome. As a result, these new high-throughput technologies have facilitated progress in the understanding and diagnosis of genetic syndromes and cancers, two disorders traditionally considered to be separate diseases but that can share causal genetic alterations in a group of developmental disorders associated with congenital malformations and cancer risk. The purpose of this work is to review these syndromes as an example of a group of disorders that has been included in a panel of genes for NGS analysis. We also highlight the relationship between development and cancer and underline the connections between these syndromes.

Hereditary Pheochromocytoma

INTRODUCTION

Pheochromocytomas (PHEO) and paragangliomas (PGL) are rare neuroendocrine tumors with an estimated occurrence of 2 to 5 patients per million per year and an incidence of about 1 per 100 000 in the general population. These tumors may arise sporadically or be associated to various syndromes, namely multiple endocrine neoplasia type 2, neurofibromatosis type 1, Von Hippel-Lindau syndrome, and hereditary paraganglioma-pheochromocytoma syndromes.

OBJECTIVES

This article aims to review the current epidemiology, pathogenesis, clinical presentation, and genetic aspects of syndromes associated with hereditary PHEO/PGL.

METHODS

The literature research, conducted at PubMed database, included review articles, published from February 2009 to February 2014, written in English or Portuguese, using as query: "Hereditary AND Pheochromocytoma."

CONCLUSION

These tumors can be part of a myriad hereditary conditions that are not yet fully understood. Nevertheless, important systemic symptoms and even fatal outcomes can occur. Knowledge of these hereditary conditions can ensure a more efficient detection, treatment, and even prevention of these neuroectodermal tumors, thus new tests and studies should be conducted.

Cancer risks for relatives of children with cancer

We determined the extent and distribution of cancers in relatives of 379 children newly diagnosed with cancer. Family history was collected from 1,337 first-degree and 3,399 second-degree relatives and incidence compared with national age- and gender-specific rates. Overall, 14 children (3.7%) had a relative with a history of childhood cancer and 26 children (6.9%) had a first-degree relative with a history of cancer, with only one of these having an identifiable familial cancer syndrome. There was a higher than expected incidence of childhood cancer among first-degree relatives (parents and siblings) (standardized incidence ratio (SIR) 1.43; 95% CI 0.54–5.08). There was also a higher than expected incidence of adult cancers among first-degree relatives (SIR 1.45; 95% CI 0.93–2.21), particularly in females (SIR 1.82; 95% CI 1.26–3.39). The increased family cancer history in first-degree females was largely attributable to an effect in mothers (SIR 1.78; 95% CI 1.27–3.33). The gender-specific association was reflected in higher than expected incidence rates of breast cancer in both mothers (SIR 1.92; 95% CI 0.72–6.83) and aunts (SIR 1.64; 95% CI 0.98–2.94). These findings support the hypothesis that previously undetected familial cancer syndromes contribute to childhood cancer.