Recognition of genetic predisposition in pediatric cancer patients: An easy-to-use selection tool

Improving Detection of Cancer Predisposition Syndromes in Pediatric Oncology

Implementation and adherence to consensus statement criteria for referral of pediatric cancer patients for genetic evaluation are critical to identify the 5% to 10% with a genetic cancer predisposition syndrome. The authors implemented a Plan-Do-Study-Act quality improvement initiative aimed at increasing referrals of at-risk patients. Retrospective chart review was followed by educational intervention-with impact assessed over a 9-month prospective chart review. Referral rate improved >2-fold and there was an improvement in documented oncologic history to at least a third-degree relative. The integration of quality improvement can be an effective tool to improve the referral of patients with an elevated risk for a cancer predisposition syndrome.

Comprehensive germline-genomic and clinical profiling in 160 unselected children and adolescents with cancer

In childhood cancer, the frequency of cancer-associated germline variants and their inheritance patterns are not thoroughly investigated. Moreover, the identification of children carrying a genetic predisposition by clinical means remains challenging. In this single-center study, we performed trio whole-exome sequencing and comprehensive clinical evaluation of a prospectively enrolled cohort of 160 children with cancer and their parents. We identified in 11/160 patients a pathogenic germline variant predisposing to cancer and a further eleven patients carried a prioritized VUS with a strong association to the cancerogenesis of the patient. Through clinical screening, 51 patients (31.3%) were identified as suspicious for an underlying cancer predisposition syndrome (CPS), but only in ten of those patients a pathogenic variant could be identified. In contrast, one patient with a classical CPS and ten patients with prioritized VUS were classified as unremarkable in the clinical work-up. Taken together, a monogenetic causative variant was detected in 13.8% of our patients using WES. Nevertheless, the still unclarified clinical suspicious cases emphasize the need to consider other genetic mechanisms including new target genes, structural variants, or polygenic interactions not previously associated with cancer predisposition.

Diagnostic difficulties and possibilities of NF1-like syndromes in childhood

BACKGROUND

Neurofibromatosis type 1 (NF1), which is caused by heterozygous inactivating pathogenic variants in the NF1, has poor phenotypic expressivity in the early years of life and there are numerous conditions, including many other tumor predisposition syndromes, that can mimic its appearance. These are collectively termed NF1-like syndromes and are also connected by their genetic background. Therefore, the NF1's clinical diagnostic efficiency in childhood could be difficult and commonly should be completed with genetic testing.

METHODS

To estimate the number of syndromes/conditions that could mimic NF1, we compiled them through an extensive search of the scientific literature. To test the utility of NF1's National Institutes of Health (NIH) clinical diagnostic criteria, which have been in use for a long time, we analyzed the data of a 40-member pediatric cohort with symptoms of the NF1-like syndromes' overlapping phenotype and performed NF1 genetic test, and established the average age when diagnostic suspicion arises. To facilitate timely identification, we compiled strongly suggestive phenotypic features and anamnestic data.

RESULTS

In our cohort the utility of NF1's clinical diagnostic criteria were very limited (sensitivity: 80%, specificity: 30%). Only 53% of children with clinically diagnosed NF1 had a detectable NF1 pathogenic variation, whereas 40% of patients without fulfilled clinical criteria tested positive. The average age at first genetic counseling was 9 years, and 40% of children were referred after at least one tumor had already been diagnosed. These results highlight the need to improve NF1-like syndromes' diagnostic efficiency in childhood. We collected the most extensive spectrum of NF1-like syndromes to help the physicians in differential diagnosis. We recommend the detailed, non-invasive clinical evaluation of patients before referring them to a clinical geneticist.

CONCLUSIONS

Early diagnosis of NF1-like syndromes can help to prevent severe complications by appropriate monitoring and management. We propose a potential screening, diagnostic and management strategy based on our findings and recent scientific knowledge.

The paradigm of hematological malignant versus non-malignant manifestations, driven by primary immunodeficiencies: a complex interplay

Hematological malignancies (HM) developed on underlying primary immunodeficiencies (PID) are rare and of unusual features. Differentiating between malignant and non-malignant lymphoproliferation in cases of pediatric hematology and oncology and revealing their molecular predisposition demonstrate the complex interplay between PID and HM. We retrospectively studied a case series of seven pediatric patients, all with PID with manifestations raising suspicion for HM or hypereosinophilic syndrome (HES) or confirmed HM of lymphoid origin. Combined immunodeficiency (CID) without detection of a known mutated gene or with ataxia-telangiectasia (AT), STAT3 gain of function (GOF), DOCK8 deficiency, and CTLA4 deficiency were diagnosed in three, one, one, one, and one patient, respectively. Acute lymphoblastic leukemia and Hodgkin lymphoma followed by second primary Burkitt lymphoma were diagnosed in one patient with CID each, while lymphomatoid granulomatosis in one patient with AT. Lymphoproliferative disease occurred in STAT3 GOF, CTLA4 deficiency and CID, one patient each, and idiopathic HES in DOCK8 deficiency (median age at presentation of PID or any hematological manifestation: four years). Four patients underwent hematopoietic cell transplantation (HCT) for STAT3 GOF, DOCK8 deficiency and CID in one, one, and two cases, respectively (median age: 10 years). At the last follow-up, all transplanted patients were alive. Reporting on patients' phenotype, genotype and course of disease shed light on the prevalence, characteristics, and pathophysiology of HM complicating PID. Discriminating the non-yet malignant lymphoproliferation from its malignant equivalent on the same pathophysiology background proved of additional value. Outcomes of PID after HCT, herein reported, are favorable.

Review of guidelines for the identification and clinical care of patients with genetic predisposition for hematological malignancies

Since WHO has recognized myeloid neoplasms with germline predisposition as a new entity in 2016, it has become increasingly clear that diagnosing familial leukemia has critical implications for both the patient and his/her family, and that interdisciplinary teams of hematologists and clinical geneticists should provide care for this specific patient group. Here, we summarize consensus criteria for the identification and screening of patients with genetic predisposition for hematologic malignancies, as provided by different working groups, e.g. by the Nordic MDS group and the AACR. In addition to typical clinical features, results from targeted deep sequencing may point to a genetic predisposition. We review strategies to distinguish somatic and germline variants and discuss recommendations for genetic analyses aiming to identify the underlying genetic variant that should follow established quality criteria to detect both SNVs and CNVs and to determine the pathogenicity of genetic variants. To enhance the knowledge about hematologic neoplasms with germline predisposition we recommend archiving clinical and genetic data and archiving them in international registries.

Childhood Cancer: Occurrence, Treatment and Risk of Second Primary Malignancies

Cancer represents the leading cause of disease-related death and treatment-associated morbidity in children with an increasing trend in recent decades worldwide. Nevertheless, the 5-year survival of childhood cancer patients has been raised impressively to more than 80% during the past decades, primarily attributed to improved diagnostic technologies and multiagent cytotoxic regimens. This strong benefit of more efficient tumor control and prolonged survival is compromised by an increased risk of adverse and fatal late sequelae. Long-term survivors of pediatric tumors are at the utmost risk for non-carcinogenic late effects such as cardiomyopathies, neurotoxicity, or pneumopathies, as well as the development of secondary primary malignancies as the most detrimental consequence of genotoxic chemo- and radiotherapy. Promising approaches to reducing the risk of adverse late effects in childhood cancer survivors include high precision irradiation techniques like proton radiotherapy or non-genotoxic targeted therapies and immune-based treatments. However, to date, these therapies are rarely used to treat pediatric cancer patients and survival rates, as well as incidences of late effects, have changed little over the past two decades in this population. Here we provide an overview of the epidemiology and etiology of childhood cancers, current developments for their treatment, and therapy-related adverse late health consequences with a special focus on second primary malignancies.

T-cell lymphoblastic lymphoma and leukemia: different diseases from a common premalignant progenitor?

T-cell lymphoblastic lymphoma (T-LBL) and lymphoblastic leukemia (T-ALL) represent malignancies that arise from the transformation of immature precursor T cells. Similarities in T-LBL and T-ALL have raised the question whether these entities represent 1 disease or reflect 2 different diseases. The genetic profiles of T-ALL have been thoroughly investigated over the last 2 decades, whereas fairly little is known about genetic driver mutations in T-LBL. Nevertheless, the comparison of clinical, immunophenotypic, and molecular observations from independent T-LBL and T-ALL studies lent strength to the theory that T-LBL and T-ALL reflect different presentations of the same disease. Alternatively, T-LBL and T-ALL may simultaneously evolve from a common malignant precursor cell, each having their own specific pathogenic requirements or cellular dependencies that differ among stroma-embedded blasts in lymphoid tissues compared with solitary leukemia cells. This review aims to cluster recent findings with regard to clinical presentation, genetic predisposition, and the acquisition of additional mutations that may give rise to differences in gene expression signatures among T-LBL and T-ALL patients. Improved insight in T-LBL in relation to T-ALL may further help to apply confirmed T-ALL therapies to T-LBL patients.

Eye Tumors in Childhood as First Sign of Tumor Predisposition Syndromes: Insights from an Observational Study Conducted in Germany and Austria

Simple Summary

Eye tumors in children are very rare. In Europe, these eye tumors are nearly always diagnosed early and cure rates are high. However, eye tumors in childhood often occur as the first sign of a genetic tumor predisposition syndrome. This study collected data of children with malignant eye tumors diagnosed in five years in Germany and Austria to learn about the association of eye tumors in childhood with tumor predisposition syndrome. The study recruited 300 children with malignant eye tumors in childhood. In the here-presented cohort, more than 40% of eye tumors were associated with rare tumor predisposition syndromes. For this reason, all children with eye tumors and their families should receive genetic counseling for a tumor predisposition syndrome. Children with a genetic predisposition to cancer should receive a tailored surveillance, including detailed history, physical examination and, if indicated, imaging to screen for other cancers later in life.

Abstract

Retinoblastoma and other eye tumors in childhood are rare diseases. Many eye tumors are the first signs of a genetic tumor predisposition syndrome and the affected children carry a higher risk of developing other cancers later in life. Clinical and genetic data of all children with eye tumors diagnosed between 2013–2018 in Germany and Austria were collected in a multicenter prospective observational study. In five years, 300 children were recruited into the study: 287 with retinoblastoma, 7 uveal melanoma, 3 ciliary body medulloepithelioma, 2 retinal astrocytoma, 1 meningioma of the optic nerve extending into the eye. Heritable retinoblastoma was diagnosed in 44% of children with retinoblastoma. One child with meningioma of the optic nerve extending into the eye was diagnosed with neurofibromatosis 2. No pathogenic constitutional variant in DICER1 was detected in a child with medulloepithelioma while two children did not receive genetic analysis. Because of the known association with tumor predisposition syndromes, genetic counseling should be offered to all children with eye tumors. Children with a genetic predisposition to cancer should receive a tailored surveillance including detailed history, physical examinations and, if indicated, imaging to screen for other cancer. Early detection of cancers may reduce mortality.

Clinical value of a screening tool for tumor predisposition syndromes in childhood cancer patients (TuPS): a prospective, observational, multi-center study

Recognizing a tumor predisposition syndrome (TPS) in a child with cancer is of clinical relevance. Earlier we developed a screening tool to increase diagnostic accuracy and clinical efficiency of identifying TPSs in children with cancer. Here we report on the value of this tool in clinical practice. TuPS is a prospective, observational, multi-center study including children newly diagnosed with cancer from 2016 to 2019 in the Netherlands. Children in whom a TPS had been diagnosed before the cancer diagnosis were excluded. The screening tool consists of a checklist, 2D and 3D photographic series and digital assessment of these by a clinical geneticist. If a TPS was suspected, the patient was assessed positive and referred for routine genetic consultation. Primary aim was to assess the clinical value of this new screening tool. Of the 363 included patients, 57% (208/363) were assessed positive. In 15% of patients (32/208), the 2D photographic series with (n = 12) or without (n = 20) 3D photographs were decisive in the positive assessment. In 2% (4/208) of positive assessed patients, a TPS was diagnosed, and in an additional 2% (4/208) a germline variant of uncertain significance was found. Thirty-five negatively assessed patients were evaluated through routine genetic consultation as controls, in none a TPS was detected. Using the screening tool, 57% of the patients were assessed as suspected for having a TPS. No false negative results were identified in the negative control group in the clinical care setting. The observed prevalence of TPS was lower than expected, due to selection bias in the cohort.

Effective identification of cancer predisposition syndromes in children with cancer employing a questionnaire

Approximately 10% of children with newly diagnosed cancer have a cancer predisposition syndrome (CPS). The optimal diagnostic approach to identify them among children diagnosed with cancer is unknown.

OBJECTIVE

 To determine whether the use of a one-page questionnaire can improve the CPS diagnosis among children with an oncologic condition.

DESIGN

 Comparative effectiveness research.

SETTING

 Referral center for children with cancer.

RESULTS

 739 children diagnosed with an oncologic condition between 2012 and 2019. All children with a newly diagnosed oncologic condition presenting to Hannover Medical School between January 1st 2017 and December 31st 2019 were prospectively evaluated with a CPS questionnaire. Children in whom the questionnaire suggested the need of a genetic workup were further evaluated. All children diagnosed with an oncologic condition between January 1st 2012 and December 31st 2016 served as control. The CPS diagnoses established during both time periods were evaluated and compared. A CPS was diagnosed in 27 out of 287 children (9.4%) during the questionnaire period versus 24 out of 452 children (5.3%) during the control period (P = 0.032).

CONCLUSION

 The CPS questionnaire appears to significantly improve the diagnosis of children with CPS among children with a newly diagnosed oncologic condition.

Proportion of children with cancer that have an indication for genetic counseling and testing based on the cancer type irrespective of other features

In children with cancer, specific clinical features such as physical anomalies, occurrence of cancer in young relatives, specific cancer histologies, and unique mutation/methylation signatures may indicate the presence of an underlying cancer predisposition syndrome (CPS). The proportion of children with a cancer type suggesting a CPS among all children with cancer is unknown. To determine the proportion of children with cancer types suggesting an underlying CPS among children with cancer. We evaluated the number of children with cancer types strongly associated with CPS diagnosed in Germany between 2007 and 2016. Data were obtained from various sources including two national pediatric pathology reference laboratories for brain and solid tumors, respectively, various childhood cancer trial offices as well as the German Childhood Cancer Registry. Among 21,127 children diagnosed with cancer between 2007 and 2016, 2554 (12.1%) had a cancer type strongly associated with a CPS. The most common diagnoses were myelodysplastic syndrome and juvenile myelomonocytic leukemia, retinoblastoma, malignant peripheral nerve sheath tumor, infantile myofibromatosis, medulloblastoma^SHH, rhabdoid tumor as well as atypical teratoid/rhabdoid tumor. Based on cancer type only, 12.1% of all children with cancer have an indication for a genetic evaluation. Pediatric oncology patients require access to genetic counselling and testing.

Clinical practice of a genetics referral selection tool in pediatric cancer patients

There are few guidelines for genetic counseling and management of pediatric cancer patients with probable cancer predisposition. In this study, we used a previously proposed patient selection tool by Jongmans and discussed the findings in regard to pediatric cancer patients we treated. Pediatric solid tumor patients who were treated in Kocaeli University Department of Pediatric Oncology were evaluated with the five main questions in Jongmans' referral tool. All of the patients and records of diagnostic imaging were examined and analyzed. One-hundred-twenty-three patients participated in the study. The most common indication for genetic counseling was 'consanguinity of the parents' with '≥2 malignancies at childhood age' following it. Fifty-two (42.28%) patients had indication for genetic counseling. We recommend developing and using genetics counseling selection tools such as Jongmans' which helps clinicians differentiate patients with probable cancer predisposition.

Second malignant neoplasms after treatment of non-Hodgkin's lymphoma-a retrospective multinational study of 189 children and adolescents

Data on the spectrum of second malignant neoplasms (SMNs) after primary childhood non-Hodgkin's lymphoma (NHL) are scarce. One-hundred-and-eighty-nine NHL patients diagnosed in a 30 years period of 1980-2010 developing an SMN were retrieved from 19 members of the European Intergroup for Childhood NHL and/or the international Berlin-Frankfurt-Münster Study Group. Five subgroups of SMNs were identified: (1) myeloid neoplasms (n = 43; 23%), (2) lymphoid neoplasms (n = 51; 27%), (3) carcinomas (n = 48; 25%), (4) central nervous system (CNS) tumors (n = 19; 10%), and (5) "other" SMNs (n = 28; 15%). In 37 patients (20%) preexisting disorders were reported with 90% having any kind of cancer predisposition syndrome (CPS). For the 189 primary NHL patients, 5-year overall survival (OS) after diagnosis of an SMN was 56 ± 4%, being worst for patients with preexisting disorders at 28 ± 8%. Five-year OS rates were 38 ± 8%, 59 ± 7%, 79 ± 8%, 34 ± 12%, and 62 ± 11%, respectively, for patients with myeloid and lymphoid neoplasms, carcinomas, CNS tumors, and "other" SMNs (p < 0.0001). Patients with SMNs after childhood NHL having a reported CPS, mostly mismatch repair disorders, carried a very poor prognosis. Moreover, although outcome was favorable in some subtypes of SMNs after childhood NHL (carcinomas, lymphoid neoplasms), other SMNs such as myeloid neoplasms and CNS tumors had a dismal prognosis.

Predisposition to cancer in children and adolescents

Childhood malignancies are rarely related to known environmental exposures, and it has become increasingly evident that inherited genetic factors play a substantial causal role. Large-scale sequencing studies have shown that approximately 10% of children with cancer have an underlying cancer predisposition syndrome. The number of recognised cancer predisposition syndromes and cancer predisposition genes are constantly growing. Imaging and laboratory technologies are improving, and knowledge of the range of tumours and risk of malignancy associated with cancer predisposition syndromes is increasing over time. Consequently, surveillance measures need to be constantly adjusted to address these new findings. Management recommendations for individuals with pathogenic germline variants in cancer predisposition genes need to be established through international collaborative studies, addressing issues such as genetic counselling, cancer prevention, cancer surveillance, cancer therapy, psychological support, and social-ethical issues. This Review represents the work by a group of experts from the European Society for Paediatric Oncology (SIOPE) and aims to summarise the current knowledge and define future research needs in this evolving field.

Genetic predisposition to fetal and neonatal cancer

BACKGROUND

Neonatal tumors represent an extremely rare and heterogeneous disease with an unknown etiology. Due to its early onset, it has been proposed that genetic factors could play a critical role; however, germline genetic analysis is not usually performed in neonatal cancer patients PATIENTS AND METHODS: To improve the identification of cancer genetic predisposition syndromes, we retrospectively review clinical characteristics in 45 patients with confirmed tumor diagnosis before 28 days of age, and we carried out germline genetic analysis in 20 patients using next-generation sequencing and directed sequencing.

RESULTS

The genetic studies did not find any germline mutation except patients diagnosed with bilateral retinoblastoma who harbored RB1 germline mutations.

CONCLUSIONS

Our results suggest that genetic factors have almost no higher impact in most neonatal tumors. However, since the heterogeneity of the tumors and the small sample size analyzed, we recommend complementary and centralized germline studies to discard the early onset as an additional criterion to take into account to improve the identification of cancer genetic predisposition syndromes in neonates.

Nationwide germline whole genome sequencing of 198 consecutive pediatric cancer patients reveals a high incidence of cancer prone syndromes

PURPOSE

Historically, cancer predisposition syndromes (CPSs) were rarely established for children with cancer. This nationwide, population-based study investigated how frequently children with cancer had or were likely to have a CPS.

METHODS

Children (0-17 years) in Denmark with newly diagnosed cancer were invited to participate in whole-genome sequencing of germline DNA. Suspicion of CPS was assessed according to Jongmans'/McGill Interactive Pediatric OncoGenetic Guidelines (MIPOGG) criteria and familial cancer diagnoses were verified using population-based registries.

RESULTS

198 of 235 (84.3%) eligible patients participated, of whom 94/198 (47.5%) carried pathogenic variants (PVs) in a CPS gene or had clinical features indicating CPS. Twenty-nine of 198 (14.6%) patients harbored a CPS, of whom 21/198 (10.6%) harbored a childhood-onset and 9/198 (4.5%) an adult-onset CPS. In addition, 23/198 (11.6%) patients carried a PV associated with biallelic CPS. Seven of the 54 (12.9%) patients carried two or more variants in different CPS genes. Seventy of 198 (35.4%) patients fulfilled the Jongmans' and/or MIPOGG criteria indicating an underlying CPS, including two of the 9 (22.2%) patients with an adult-onset CPS versus 18 of the 21 (85.7%) patients with a childhood-onset CPS (p = 0.0022), eight of the additional 23 (34.8%) patients with a heterozygous PV associated with biallelic CPS, and 42 patients without PVs. Children with a central nervous system (CNS) tumor had family members with CNS tumors more frequently than patients with other cancers (11/44, p = 0.04), but 42 of 44 (95.5%) cases did not have a PV in a CPS gene.

CONCLUSION

These results demonstrate the value of systematically screening pediatric cancer patients for CPSs and indicate that a higher proportion of childhood cancers may be linked to predisposing germline variants than previously supposed.

Pediatric Lymphoma and Solid Tumors Associated With Cancer Susceptibility Syndromes

The aim of this study was to determine cancer susceptibility syndromes (CSSs) in children with lymphoma and solid tumors and to evaluate their effects on overall survival rates. Between 2006 and 2019, the oncologic charts of 672 patients who were followed-up with a diagnosis of lymphoma and solid tumor in our clinic were retrospectively reviewed. CSSs were detected in 42 children (6.25%). The most common CSS was DNA damage repair defects/genetic instability (in 18 of 42 patients with CSSs, 42.8%). In the patients with CSSs, 48 different cancers developed. The most common types of cancer were lymphoma (n: 10, 21%) and high-grade glial tumor (n: 9, 19%). The lymphoma subgroups were very rare childhood lymphomas, such as gray zone lymphoma and marginal zone lymphoma. The overall survival rates for patients with DNA damage repair defects/genetic instability; with CSSs other than DNA damage repair defects/patients with genetic instability syndrome; and without any CSS, were 9.7%, 65.1%, and 68.7%, respectively. The overall survival rate for patients with DNA damage repair defects/patients with genetic instability syndrome was lower than both patients with CSSs other than DNA damage repair defects/genetic instability syndrome (P=0.002) and those without any CSS (P<0.0001). CSSs should be kept in mind in children with cafe au lait spots; syndromic features; a family history of cancer, especially in siblings; and rare childhood cancers.

Precision oncology: A primer for pediatric surgeons from the APSA cancer committee

Although most children with cancer can be cured of their disease, a subset of patients with adverse tumor types or biological features, and those with relapsed or refractory disease have significantly worse prognosis. Furthermore, current cytotoxic therapy is associated with significant late effects. Precision oncology, using molecular therapeutics targeted against unique genetic features of the patient's tumor, offers the potential to transform the multimodal therapy for these patients. Potentiated by advances in sequencing technology and molecular therapeutic development, and accelerated by large-scale multi-institutional basket trials, the field of pediatric precision oncology has entered the mainstream. These novel therapeutics have important implications for surgical decision making, as well as pre- and postoperative care. This review summarizes the current state of precision medicine in pediatric oncology including the active North American and European precision oncology clinical trials. LEVEL OF EVIDENCE: Treatment study Level V.

Linking population-based registries to identify familial cancer risk in childhood cancer

BACKGROUND

Linked population-based registries provide a unique source for identification of new family cancer syndromes and for elucidating risk of early-onset cancer in close relatives of cancer patients.

METHODS

Using the Finnish Cancer Registry, we identified 9078 probands who had been diagnosed with cancer at <21 years of age between 1970 and 2012. Siblings, offspring, parents, nephews, and nieces of probands were identified from the Population Registry. Childhood and young adult (ChYA) cancer diagnoses (age 0-39 years) in relatives were identified by linking to the Finnish Cancer Registry. The relative risk of ChYA cancer in family members of probands was estimated using standardized incidence ratios (SIRs).

RESULTS

Among 58,010 family members of the 9078 probands, 363 ChYA cancers were diagnosed, 324 of which were expected (SIR, 1.12; 95% CI, 1.01-1.24). The risk of ChYA cancer was elevated both in offspring (SIR, 2.25; 95% CI, 1.51-3.24) and in siblings (SIR, 1.17; 95% CI, 1.01-1.36). Offspring of probands with retinoblastoma were at highest risk (SIR, 75.85; 95% CI, 32.75-149.45); risks were also elevated for siblings of probands with lymphoma (SIR, 1.62; 95% CI, 1.14-2.25). Known cancer predisposition syndromes were observed in 29 (66%) of 44 sibling pairs with cancers diagnosed at <21 years of age and in 20% of the 135 families with a childhood cancer proband whose sibling was diagnosed with a young adult malignancy.

CONCLUSION

Linked population-based registry data indicate a modestly increased risk of ChYA in relatives of children with cancer. Some of the observed cancer clusters in the cohort suggest novel patterns and familial cancer syndromes.

Pediatric Somatic Tumor Sequencing Identifies Underlying Cancer Predisposition

PURPOSE

The diagnosis of cancer predisposition in pediatric patients with cancer is vital for treatment decisions, surveillance, and management of at-risk family members. Somatic tumor testing can identify potential underlying constitutional variants that confer increased cancer risk. Here, we report the characteristics of constitutional variants identified through tumor testing.

MATERIALS AND METHODS

Data were abstracted from medical record review of 1,023 patients who received inhouse somatic tumor testing over a 28-month period. Patients were identified for testing using referral criteria developed as a collaboration between genomic diagnostics, pathology, and oncology. Characteristics of patients who underwent constitutional testing, including family history and variant loss of heterozygosity, were tracked.

RESULTS

From 1,023 patients who underwent somatic tumor sequencing in a 28-month period, 210 variants were identified in 141 patients (13.8%) that were concerning for cancer predisposition syndromes requiring intervention. A total of 73 variants in 41 patients have undergone clinical confirmatory testing thus far. Of these, 26 variants were confirmed to be constitutionally present (35.6%). Among patients tested, 23 (56.1%) of 41 total patients were diagnosed with a cancer predisposition syndrome.

CONCLUSION

Our data demonstrate that more than one third of variants in tumor somatic sequencing that were concerning for underlying cancer predisposition were constitutionally confirmed. Overall, somatic tumor testing identified potential cancer predisposition syndromes in pediatric patients, and some would not have been identified on the basis of clinical history alone.

How I approach hereditary cancer predisposition in a child with cancer

Approximately 10% of all children with cancer are affected by a monogenic cancer predisposition syndrome. This has important implications for both the child and her/his family. The assessment of hereditary cancer predisposition is a challenging task for clinicians and genetic counselors in daily routine. It includes consideration of tumor genetics, specific features of the patient, and the medical/family history. To keep up with the pace of this rapidly evolving and increasingly complex field of genetic susceptibility, we suggest a systematic approach for the evaluation of the child with cancer and her/his family by an interdisciplinary team specialized in hereditary cancer predisposition.

Integrating genetic counseling and testing in the pediatric oncology setting: Parental attitudes and influencing factors

BACKGROUND

Cancer predisposition syndromes (CPS) are caused by germline pathogenic variants that put an individual at increased risk of developing cancer throughout their lifetime. It is estimated that approximately 10-15% of children with cancer have an underlying CPS. Although research has investigated the clinical utility of genetic testing for children diagnosed with cancer, this study aimed to gain a deeper understanding of parental attitudes toward genetic testing in this population.

PROCEDURE

Attitudes toward genetic counseling and testing among parents of children diagnosed with cancer were solicited through questionnaires distributed to a pediatric cancer clinic and online support groups. Quantitative data were analyzed using descriptive statistics and chi-square tests for association.

RESULTS

The majority of participants had prior knowledge of genetic counseling (64.3%), yet most were not offered genetic counseling (59.5%). Fifty percent of parents reported interest in pursuing genetic counseling/testing and 31.0% reported uncertainty. Statistically significant associations were identified between interest in genetic counseling/testing and the child's age at diagnosis, child's sex, and participant annual income (P < .05).

CONCLUSIONS

Parents of children diagnosed with cancer generally expressed interest in genetic counseling/testing; however, notable uncertainty was also reported. In light of this uncertainty, genetic counselors have an ideal skill set to engage families in their decision-making process as they weigh the benefits and drawbacks to pursuing genetic testing among this population. Demonstrated parental receptiveness to genomic technologies supports expansion of genetics providers in pediatric oncology care.

[Genetic predisposition to childhood cancer]

Tackling the topic of genetic predisposition to childhood cancer requires close co-operation between pathologists, pediatric oncologists, and human geneticists. It is not just about the precise diagnosis and the most effective treatment of the cancer, but also to prevent further cancerous diseases for those affected and also their family members. On the basis of examples such as Li-Fraumeni syndrome, constitutional mismatch repair deficiency (CMMRD), medullo- and neuroblastoma, as well as hematological neoplasias, we will discuss the criteria for tumor predisposition genetic syndromes, the relationship between somatic and germline variants, and the immediate clinical consequences. In some cases, the diagnosis of a genetic tumor predisposition syndrome has immediate consequences for the treatment, e. g. to avoid radiotherapy for Li-Fraumeni syndrome, which would otherwise significantly increase the probability of secondary, independent tumors. Predictive diagnostics can be offered to identify the family members who carry the pathogenic variant. Because of their increased tumor risk, they should be integrated into cancer surveillance programs. Evidence-based data show that this significantly improves overall survival.

Molecular Profiling of Hard-to-Treat Childhood and Adolescent Cancers

IMPORTANCE

Little progress in pediatric cancer treatment has been noted in the past decade, urging the development of novel therapeutic strategies for adolescents and children with hard-to-treat cancers. Use of comprehensive molecular profiling in the clinical management of children and adolescents with cancer appears a suitable approach to improve patient care and outcomes, particularly for hard-to-treat cases.

OBJECTIVE

To assess the feasibility of identifying potentially actionable mutations using next-generation sequencing-based assays in a clinically relevant time frame.

DESIGN, SETTING, AND PARTICIPANTS

This diagnostic study reports the results of the TRICEPS study, a prospective genome sequencing study conducted in Québec, Canada. Participants, aged 18 years or younger at diagnosis, with refractory or relapsed childhood and adolescent cancers were enrolled from April 2014 through January 2018. Whole-exome sequencing (WES) of matched tumor normal samples and RNA sequencing of tumor were performed to identify single-nucleotide variants, fusion transcripts, differential gene expression, and copy number alterations. Results reviewed by a team of experts were further annotated, synthesized into a report, and subsequently discussed in a multidisciplinary molecular tumor board.

MAIN OUTCOMES AND MEASURES

Molecular profiling of pediatric patients with hard-to-treat cancer, identification of actionable and targetable alteration needed for the management of these patients, and proposition of targeted and personalized novel therapeutic strategies.

RESULTS

A total of 84 patients with hard-to-treat cancers were included in the analysis. These patients had a mean (range) age of 10.1 (1-21) years and a similar proportion of male (45 [54%]) and female (39 [46%]). Sixty-two patients (74%) had suitable tissues for multimodal molecular profiling (WES and RNA sequencing). The process from DNA or RNA isolation to genomic sequencing and data analysis steps took a median (range) of 24 (4-41) days. Potentially actionable alterations were identified in 54 of 62 patients (87%). Actions were taken in 22 of 54 patients (41%), and 18 (33%) either were on a second or third line of treatment, were in remission, or had stable disease and thus no actions were taken.

CONCLUSIONS AND RELEVANCE

Incorporating genomic sequencing into the management of hard-to-treat childhood and adolescent cancers appeared feasible; molecular profiling may enable the identification of potentially actionable alterations with clinical implications for most patients, including targeted therapy and clinically relevant information of diagnostic, prognostic, and monitoring significance.

Primary Immunodeficiency and Cancer Predisposition Revisited: Embedding Two Closely Related Concepts Into an Integrative Conceptual Framework

Common understanding suggests that the normal function of a "healthy" immune system safe-guards and protects against the development of malignancies, whereas a genetically impaired one might increase the likelihood of their manifestation. This view is primarily based on and apparently supported by an increased incidence of such diseases in patients with specific forms of immunodeficiencies that are caused by high penetrant gene defects. As I will review and discuss herein, such constellations merely represent the tip of an iceberg. The overall situation is by far more varied and complex, especially if one takes into account the growing difficulties to define what actually constitutes an immunodeficiency and what defines a cancer predisposition. The enormous advances in genome sequencing, in bioinformatic analyses and in the functional in vitro and in vivo assessment of novel findings together with the availability of large databases provide us with a wealth of information that steadily increases the number of sequence variants that concur with clinically more or less recognizable immunological problems and their consequences. Since many of the newly identified hard-core defects are exceedingly rare, their tumor predisposing effect is difficult to ascertain. The analyses of large data sets, on the other hand, continuously supply us with low penetrant variants that, at least in statistical terms, are clearly tumor predisposing, although their specific relevance for the respective carriers still needs to be carefully assessed on an individual basis. Finally, defects and variants that affect the same gene families and pathways in both a constitutional and somatic setting underscore the fact that immunodeficiencies and cancer predisposition can be viewed as two closely related errors of development. Depending on the particular genetic and/or environmental context as well as the respective stage of development, the same changes can have either a neutral, predisposing and, in some instances, even a protective effect. To understand the interaction between the immune system, be it "normal" or "deficient" and tumor predisposition and development on a systemic level, one therefore needs to focus on the structure and dynamic functional organization of the entire immune system rather than on its isolated individual components alone.

Tumor risk and surveillance for children with hereditary disorders affecting growth

PURPOSE OF REVIEW

Hereditary disorders affecting growth (both overgrowth and growth retardation) are frequently associated with heightened risk of neoplastic disease. This review summarizes the tumor spectra associated with these conditions and identifies disease-specific screening approaches.

RECENT FINDINGS

An understanding of the molecular events underlying many of these growth disorders has evolved significantly over the past several years. Recognition of genotype-phenotype associations, in many cases, informs the cancer risk profile. Additionally, accumulating data suggest a benefit of rational presymptomatic surveillance for at-risk individuals, with a reduction in tumor-associated morbidity. Recent clinical practice recommendations have established risk-driven paradigms for tumor surveillance in the context of hereditary tumor predisposition syndromes, including those affecting growth.

SUMMARY

Clinicians caring for children with growth disorders should be aware of syndromic associations and the associated cancer risks. Knowledge of tumor spectra and recommended surveillance strategies may facilitate tumor diagnosis at an early stage and reduce morbidity of the disease and associated treatments.

Current Understanding and Future Research Priorities in Malignancy Associated With Inborn Errors of Immunity and DNA Repair Disorders: The Perspective of an Interdisciplinary Working Group

Patients with inborn errors of immunity or DNA repair defects are at significant risk of developing malignancy and this complication of their underlying condition represents a substantial cause of morbidity and mortality. Whilst this risk is increasingly well-recognized, our understanding of the causative mechanisms remains incomplete. Diagnosing cancer is challenging in the presence of underlying co-morbidities and frequently other inflammatory and lymphoproliferative processes. We lack a structured approach to management despite recognizing the competing challenges of poor response to therapy and increased risk of toxicity. Finally, clinicians need guidance on how to screen for malignancy in many of these predisposing immunodeficiencies. In order to begin to address these challenges, we brought together representatives of European Immunology and Pediatric Haemato-Oncology to define the current state of our knowledge and identify priorities for clinical and research development. We propose key developmental priorities which our two communities will need to work together to address, collaborating with colleagues around the world.

Clinical relevance of screening checklists for detecting cancer predisposition syndromes in Asian childhood tumours

Assessment of cancer predisposition syndromes (CPS) in childhood tumours is challenging to paediatric oncologists due to inconsistent recognizable clinical phenotypes and family histories, especially in cohorts with unknown prevalence of germline mutations. Screening checklists were developed to facilitate CPS detection in paediatric patients; however, their clinical value have yet been validated. Our study aims to assess the utility of clinical screening checklists validated by genetic sequencing in an Asian cohort of childhood tumours. We evaluated 102 patients under age 18 years recruited over a period of 31 months. Patient records were reviewed against two published checklists and germline mutations in 100 cancer-associated genes were profiled through a combination of whole-exome sequencing and multiplex ligation-dependent probe amplification on blood-derived genomic DNA. Pathogenic germline mutations were identified in ten (10%) patients across six known cancer predisposition genes: TP53, DICER1, NF1, FH, SDHD and VHL. Fifty-four (53%) patients screened positive on both checklists, including all ten pathogenic germline carriers. TP53 was most frequently mutated, affecting five children with adrenocortical carcinoma, sarcomas and diffuse astrocytoma. Disparity in prevalence of germline mutations across tumour types suggested variable genetic susceptibility and implied potential contribution of novel susceptibility genes. Only five (50%) children with pathogenic germline mutations had a family history of cancer. We conclude that CPS screening checklists are adequately sensitive to detect at-risk children and are relevant for clinical application. In addition, our study showed that 10% of Asian paediatric solid tumours have a heritable component, consistent with other populations.

The Clinical Impact of the Genomic Landscape of Mismatch Repair-Deficient Cancers

The mismatch repair (MMR) system which detects and corrects base mismatches and insertions and deletions that occur during DNA synthesis is deregulated in approximately 20% of human cancers. MMR-deficient tumors have peculiar properties, including early-onset metastatic potential but generally favorable prognosis, and remarkable response to immune therapy. The functional basis of these atypical clinical features has recently started to be elucidated. Here, we discuss how the biological and clinical features of MMR-deficient tumors might be traced back to their ability to continuously produce new somatic mutations, leading to increased levels of neoantigens, which in turn stimulate immune surveillance. SIGNIFICANCE: Tumors carrying defects in DNA MMR accumulate high levels of mutations, a feature linked to rapid tumor progression and acquisition of drug resistance but also favorable prognosis and response to immune-checkpoint blockade. We discuss how the genomic landscape of MMR-deficient tumors affects their biological and clinical behaviors.

Investigation of clinically relevant germline variants detected by next-generation sequencing in patients with childhood cancer: a review of the literature

Genetic predisposition is an important underlying cause of childhood cancer, although the proportion of patients with childhood cancer carrying predisposing pathogenic germline variants is uncertain. This review considers the pathogenic or likely pathogenic germline variants reported by six studies that used next-generation sequencing to investigate genetic predisposition in selected cohorts of patients with childhood cancer and used incompletely overlapping gene sets for analysis and interpretation. These six studies reported that 8.5%-35.5% of patients with childhood cancer carried clinically relevant germline variants. Analysis of 52 autosomal dominant cancer predisposition genes assumed common to all six studies showed that 5.5%-25.8% of patients with childhood cancer carried pathogenic or likely pathogenic germline variants in at least one of these genes. When only non-central nervous system solid tumours (excluding adrenocortical carcinomas) were considered, 8.5%-10.3% of the patients carried pathogenic or likely pathogenic germline variants in at least one of 52 autosomal dominant cancer predisposition genes. There was a lack of concordance between the genotype and phenotype in 33.3%-57.1% of the patients reported with pathogenic or likely pathogenic germline variants, most of which represented variants in autosomal dominant cancer predisposition genes associated with adult onset cancers. In summary, germline genetic testing in patients with childhood cancer requires clear definition of phenotypes and genes considered for interpretation, with potential to inform and broaden childhood cancer predisposition syndromes.

Imaging of cancer predisposition syndromes

Pediatric cancer predisposition syndromes comprise a group of diseases characterized by specific tumors or a concomitance of tumors in infants, children and adolescents, suggesting a genetic cancer susceptibility condition. Most but not all have germline pathogenic variants on genetic testing. For some children with cancer predisposition syndromes, this diagnosis is based on their own or a family history of related neoplasms, or associated clinical manifestations. These tumors have variable incidence and age of onset. Imaging encompasses investigation in symptomatic children for diagnosis, staging and monitoring for treatment response and metastatic disease, as well as surveillance for primary tumors in asymptomatic children. In this review the author focuses on the role of surveillance imaging in childhood cancer predisposition syndromes, whole-body magnetic resonance imaging (whole-body MRI) in particular. Diagnosis and staging of specific tumors are addressed elsewhere in this series. The benefits of surveillance imaging include early detection and improved outcomes and are still being established for a number of cancer predisposition syndromes. The benefits must be weighed against risks including potential technique-related issues relating to sedation or contrast agents, false-positive imaging findings, and cost - both financial and psychosocial. The author discusses general principles for whole-body MRI interpretation along with findings in specific syndromes where whole-body MRI screening is recommended, such as Li-Fraumeni syndrome.

Prevalence of hereditary cancer susceptibility syndromes in children with cancer in a highly consanguineous population

BACKGROUND & AIM

Hereditary cancer susceptibility syndromes (HCSS) are reported in up to one-third of children with cancer. Diagnosis of HCSS is crucial for implementation of surveillance protocols. We identified children who fulfilled criteria for HCSS in Saudi Arabia using the American College of Medical Genetics and Genomics (ACMG) guidelines, addressing the utility of these guidelines in a highly consanguineous population.

METHODS

This multi-center cross-sectional study recruited 1858 children with cancer between January 2011 and December 2014. HCSS criteria were based on the ACMG guidelines.

RESULTS

Seven hundred and four (40.4%) out of 1742 eligible patients fulfilled criteria for HCSS. Consanguinity was reported in 629 (38%) patients, with 50 (2.9%) first-degree, 535 (30.7%) second-degree, and 272 (15.6%) third-degree relatives affected with cancer. Two hundred and eighty eight (17.4%) leukemia and 87 (5.3%) brain tumour patients fulfilled HCSS criteria, with parental consanguinity being the most frequent criterion in both (leukemia 85.4%, brain tumors 83.9%). However, leukemia was less frequent in patients of consanguineous parents (p = 0.023).

CONCLUSION

Four out of 10 children with cancer fulfilled criteria for HCSS, most often due to consanguinity. This higher than expected prevalence suggests the need to validate consanguinity as a criterion for HCSS in highly consanguineous populations.

Recognizing and Managing Children with a Pediatric Cancer Predisposition Syndrome: A Guide for the Pediatrician

It is estimated that at least 8% to 10% of children diagnosed with cancer have an inherited cancer predisposition syndrome. Pediatricians may be called upon to (1) identify children with symptoms suggestive of cancer that require further diagnostic testing, (2) identify children who should be referred to cancer genetics based on their personal and family histories, and (3) provide primary care to children who have an inherited cancer syndrome. This review article provides a list of clinical warning signs suggestive of childhood malignancy, discusses the personal and family history "red flags" suggestive of hereditary cancer, offers checklists to help identify patients who are candidates for cancer genetics evaluation, and describes features of the major pediatric cancer syndromes involving solid tumors and surveillance guidelines. This review aims to provide the pediatrician with the tools needed to recognize, refer, and help manage children at risk for pediatric cancer syndromes. [Pediatr Ann. 2018;47(5):e204-e216.].

Pediatric Cancer Predisposition and Surveillance: An Overview, and a Tribute to Alfred G. Knudson Jr

The prevalence of childhood cancer attributable to genetic predisposition was generally considered very low. However, recent reports suggest that at least 10% of pediatric cancer patients harbor a germline mutation in a cancer predisposition gene. Although some of these children will have a family history suggestive of a cancer predisposition syndrome, many others will not. Evidence from recent pediatric studies suggests that surveillance and early detection of cancer in individuals carrying a germline cancer predisposing mutation may result in improved outcomes. However, there is a lack of consistency in the design of cancer surveillance regimens across centers both nationally and internationally. To standardize approaches, the Pediatric Cancer Working Group of the American Association for Cancer Research (AACR) convened a workshop, during which consensus screening recommendations for children with the most common cancer predisposition syndromes were developed. In general, we considered a 5% or greater chance of developing a childhood cancer to be a reasonable threshold to recommend screening. Conditions for which the cancer risk was between 1% to 5% were addressed individually. In a series of manuscripts accompanying this article, we provide recommendations for surveillance, focusing on when to initiate and/or discontinue specific screening measures, which modalities to use, and the frequency of screening. Points of controversy are also reviewed. We present the outcome of our deliberations on consensus screening recommendations for specific disorders in 18 position articles as Open Access publications, which are freely available on an AACR-managed website. Clin Cancer Res; 23(11); e1-e5. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

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.

High Yield of Pathogenic Germline Mutations Causative or Likely Causative of the Cancer Phenotype in Selected Children with Cancer

Purpose: In many children with cancer and characteristics suggestive of a genetic predisposition syndrome, the genetic cause is still unknown. We studied the yield of pathogenic mutations by applying whole-exome sequencing on a selected cohort of children with cancer.Experimental Design: To identify mutations in known and novel cancer-predisposing genes, we performed trio-based whole-exome sequencing on germline DNA of 40 selected children and their parents. These children were diagnosed with cancer and had at least one of the following features: (1) intellectual disability and/or congenital anomalies, (2) multiple malignancies, (3) family history of cancer, or (4) an adult type of cancer. We first analyzed the sequence data for germline mutations in 146 known cancer-predisposing genes. If no causative mutation was found, the analysis was extended to the whole exome.Results: Four patients carried causative mutations in a known cancer-predisposing gene: TP53 and DICER1 (n = 3). In another 4 patients, exome sequencing revealed mutations causing syndromes that might have contributed to the malignancy (EP300-based Rubinstein-Taybi syndrome, ARID1A-based Coffin-Siris syndrome, ACTB-based Baraitser-Winter syndrome, and EZH2-based Weaver syndrome). In addition, we identified two genes, KDM3B and TYK2, which are possibly involved in genetic cancer predisposition.Conclusions: In our selected cohort of patients, pathogenic germline mutations causative or likely causative of the cancer phenotype were found in 8 patients, and two possible novel cancer-predisposing genes were identified. Therewith, our study shows the added value of sequencing beyond a cancer gene panel in selected patients, to recognize childhood cancer predisposition. Clin Cancer Res; 24(7); 1594-603. ©2018 AACR.

Pediatric cancer genetics

PURPOSE OF REVIEW

The current review will focus on the current knowledge of the contribution of both germline and somatic mutations to the development and management of cancer in pediatric patients.

RECENT FINDINGS

It has long been thought that genetic mutations in both germline and somatic cells can contribute to the development of cancer in pediatric patients. With the recent advances in genomic technologies, there are now over 500 known cancer predisposition genes. Recent studies have confirmed an 8.5-14% germline mutation rate in cancer predisposition genes in pediatric cancer patients.

SUMMARY

The discovery of both germline and somatic cells mutation(s) in pediatric cancer patients not only aids in the management of current disease, but can also have direct implications for future management as well as the medical management of family members.

Using family history forms in pediatric oncology to identify patients for genetic assessment

OBJECTIVE

We set out to identify and offer genetic testing to the 5%-10% of pediatric cancer patients who have been estimated to carry germline mutations in inherited cancer predisposition syndromes. Clinical genetic testing has become widely available, and thus in busy oncology clinics, tools are needed to identify patients who could benefit from a referral to genetics.

METHODS

We studied the clinical utility of administering a family history form in the pediatric oncology long-term follow-up clinic to identify patients who might have an inherited cancer predisposition syndrome. Genetic testing involved primarily Sanger sequencing in clia (Clinical Laboratory Improvement Amendments)-certified laboratories.

RESULTS

Of 57 patients who completed forms, 19 (33.3%) met criteria for referral to genetics. A significant family history of cancer was present for 4 patients, and 12 patients underwent genetic testing. Of 18 genetic tests ordered, none identified a pathogenic mutation, likely because of a small sample size and a candidate-gene approach to testing. Three families were also identified for further assessment based on a family history of breast cancer, with two of families having members eligible for BRCA1 and BRCA2 testing.

CONCLUSIONS

Genetic testing in pediatric oncology patients is important to guide the management of patients who have an inherited cancer predisposition syndrome and to identify other family members at risk when mutations are identified. When no mutations are identified, that information is often reassuring to families who are worried about siblings. However, in the absence of an identified genetic cause in a patient, some uncertainty remains.

The McGill Interactive Pediatric OncoGenetic Guidelines: An approach to identifying pediatric oncology patients most likely to benefit from a genetic evaluation

Identifying cancer predisposition syndromes in children with tumors is crucial, yet few clinical guidelines exist to identify children at high risk of having germline mutations. The McGill Interactive Pediatric OncoGenetic Guidelines project aims to create a validated pediatric guideline in the form of a smartphone/tablet application using algorithms to process clinical data and help determine whether to refer a child for genetic assessment. This paper discusses the initial stages of the project, focusing on its overall structure, the methodology underpinning the algorithms, and the upcoming algorithm validation process.

Haematological malignancies following temozolomide treatment for paediatric high-grade glioma

BACKGROUND

Temozolomide (TMZ) is widely used in high-grade glioma (HGG). There is a major concern of treatment-induced secondary haematological malignancies (SHMs). Due to the poor overall survival of HGG patients, the true incidence is yet elusive. Thus, the aim of this study was to determine the risk of SHMs following TMZ in paediatric HGG.

METHODS

We analysed 487 patients from the HIT-HGG database of the German-speaking Society of Pediatric Oncology and Hematology with follow up beyond 1 year.

RESULTS

The incidence of SHM was 7.7 ± 3.2% at 10 years. No SHM occurred in 194 patients after first-line TMZ therapy, but four out of 131 patients treated with TMZ for relapse following first-line multiagent chemotherapy experienced SHM (20% at 10 years; p = 0.041). SHMs occurred in two out of 162 patients who underwent multiagent chemotherapy without TMZ (4.1% at 10 years). Gender, patient age and acute haematological toxicity during treatment did not affect the incidence of SHMs.

CONCLUSION

Data of our cohort do not indicate an increased risk of SHM following TMZ treatment when compared to previous chemotherapy regimen. However, if TMZ is administered as a second-line treatment following conventional chemotherapy regimen, the risk might be disproportionately increasing.

Germline Genetic Predisposition to Hematologic Malignancy

Development of hematologic malignancies is driven by mutations that may be somatic or germline. Availability of next-generation DNA sequencing technologies has facilitated the development of individualized diagnostic evaluations and tailored treatment strategies. Until now, such personalized medical approaches have largely centered on prognostic stratification and treatment strategies informed by acquired somatic mutations. The role of germline mutations in children and adults with hematologic malignancies was previously underappreciated. Diagnosis of an inherited predisposition to hematologic malignancy informs choice of therapy, risk of treatment-related complications, donor selection for hematopoietic stem cell transplantation, evaluation of comorbidities, and surveillance strategies to improve clinical outcomes. The recognition that patients with inherited hematologic malignancy syndromes may present without classic clinical stigmata or suspicious family history has led to increased reliance on genetic testing, which, in turn, has raised new diagnostic challenges. Genomic testing is a rapidly evolving field with an increasing number of choices for testing for the practicing clinician to navigate. This review will discuss general approaches to diagnosis and management of patients with germline predisposition to hematology malignancies and will consider applications and limitations of genomic testing in clinical practice.

Childhood cancer predisposition syndromes-A concise review and recommendations by the Cancer Predisposition Working Group of the Society for Pediatric Oncology and Hematology

Heritable predisposition is an important cause of cancer in children and adolescents. Although a large number of cancer predisposition genes and their associated syndromes and malignancies have already been described, it appears likely that there are more pediatric cancer patients in whom heritable cancer predisposition syndromes have yet to be recognized. In a consensus meeting in the beginning of 2016, we convened experts in Human Genetics and Pediatric Hematology/Oncology to review the available data, to categorize the large amount of information, and to develop recommendations regarding when a cancer predisposition syndrome should be suspected in a young oncology patient. This review summarizes the current knowledge of cancer predisposition syndromes in pediatric oncology and provides essential information on clinical situations in which a childhood cancer predisposition syndrome should be suspected.