Concurrent Hepatoblastoma and Wilms Tumor Leading to Diagnosis of Beckwith-Wiedemann Syndrome.

Beckwith-Wiedemann syndrome (BWS) is an epigenetic overgrowth disorder and cancer predisposition syndrome caused by imprinting defects of chromosome 11p15.5-11p15.4. BWS should be considered in children with atypical presentations of embryonal tumors regardless of clinical phenotype. Risk of malignancy correlates with specific molecular subgroups of BWS making molecular subclassification important for appropriate cancer screening. We report the first case of concurrent embryonal tumors in a phenotypically normal child, leading to the diagnosis of BWS with paternal uniparental disomy and describe the molecular classification of BWS as it relates to malignancy risk, along with approach to management.

COVID-19 has changed the way we think about training future pediatric hematologists/oncologists.

COVID-19 has upended medical practice and education, but has also catalyzed enhancements in the field. Early on, a local group of researchers united to investigate the impact of the pandemic on pediatric hematology oncology (PHO). From this group, a regional educational series was established, "virtual-Symposium of Pediatric Hematology/Oncology of New York" (v-SYMPHONY). The implementation of these endeavors while PHO fellowship applications are declining has highlighted our perceptions that education, mentoring, and career expectations are not keeping up with the needs of current trainees. We describe our regional experience joining together to further education and research, and reflect on the current landscape of PHO training and workforce.

Being Precise About Precision Medicine: What Should Value Frameworks Incorporate to Address Precision Medicine? A Report of the Personalized Precision Medicine Special Interest Group.

Precision medicine is a dynamic area embracing a diverse and increasing type of approaches that allow the targeting of new medicines, screening programs or preventive healthcare strategies, which include the use of biologic markers or complex tests driven by algorithms also potentially taking account of patient preferences. The International Society for Pharmacoeconomics and Outcome Research expanded its current work around precision medicine to (1) describe the evolving paradigm of precision medicine with examples of current and evolving applications, (2) describe key stakeholders perspectives on the value of precision medicine in their respective domains, and (3) define the core factors that should be considered in a value assessment framework for precision medicine. With the ultimate goal of improving health of well-defined patient groups, precision medicine will affect all stakeholders in the healthcare system at multiple levels spanning the individual perspective to the societal perspective. For an efficient, timely and practical precision medicine value assessment framework, it will be important to address these multiple perspectives through building consensus among the stakeholders for robust procedures and measures of value aspects, including performance of precision mechanism; aligned reimbursement processes of precision mechanism and subsequent treatment; transparent expectations for evidence requirements and study designs adequately matched to the intended use of the precision mechanism and to the smaller target patient populations; recognizing the potential range of value-generation such as ruling-in and ruling-out decisions.

Clinical Utilization, Utility, and Reimbursement for Expanded Genomic Panel Testing in Adult Oncology.

PURPOSE: The routine use of large next-generation sequencing (NGS) pan-cancer panels is required to identify the increasing number of, but often uncommon, actionable alterations to guide therapy. Inconsistent coverage and variable payment is hindering NGS adoption into clinical practice. A review of test utilization, clinical utility, coverage, and reimbursement was conducted in a cohort of patients diagnosed with high-risk cancer who received pan-cancer panel testing as part of their clinical care. MATERIALS AND METHODS: The Columbia Combined Cancer Panel (CCCP), a 467-gene panel designed to detect DNA variations in solid and liquid tumors, was performed in the Laboratory of Personalized Genomic Medicine at Columbia University Irving Medical Center. Utilization was characterized at test order. Results were reviewed by a molecular pathologist, followed by a multidisciplinary molecular tumor board where clinical utility was classified by consensus. Reimbursement was reviewed after payers provided final coverage decisions. RESULTS: NGS was performed on 359 high-risk tumors from 349 patients. Reimbursement data were available for 246 cases. The most common reason providers ordered CCCP testing was for patients diagnosed with a treatment-resistant or recurrent tumor (n = 214; 61%). Findings were clinically impactful for 229 cases (64%). Molecular alterations that may inform future therapy in the event of progression or relapse were found in 42% of cases, and a targeted therapy was initiated in 23 cases (6.6%). The majority of tests were denied coverage by payers (n = 190; 77%). On average, insurers reimbursed 10.75% of the total NGS service charge. CONCLUSION: CCCP testing identified clinically impactful alterations in 64% of cases. Limited coverage and low reimbursement remain barriers, and broader reimbursement policies are needed to adopt pan-cancer NGS testing that benefits patients into clinical practice.

Identification of a secondary RET mutation in a pediatric patient with relapsed acute myeloid leukemia leads to the diagnosis and treatment of asymptomatic metastatic medullary thyroid cancer in a parent: a case for sequencing the germline.

The incorporation of tumor-normal genomic testing into oncology can identify somatic mutations that inform therapeutic measures but also germline variants associated with unsuspected cancer predisposition. We describe a case in which a RET variant was identified in a 3-yr-old male with relapsed leukemia. Sanger sequencing revealed the patient's father and three siblings carried the same variant, associated with multiple endocrine neoplasia 2A (MEN2A). Evaluation of the father led to the diagnosis and treatment of metastatic medullary thyroid carcinoma. Detection of RET mutations in families with hereditary MTC allows for genetic risk stratification and disease surveillance to reduce morbidity and mortality.

Whole-Genome and Whole-Exome Sequencing in Pediatric Oncology: An Assessment of Parent and Young Adult Patient Knowledge, Attitudes, and Expectations.

PURPOSE: The complexity of results generated from whole-genome sequencing (WGS) and whole-exome sequencing (WES) adds challenges to obtaining informed consent in pediatric oncology. Little is known about knowledge of WGS and WES in this population, and no validated tools exist in pediatric oncology. METHODS: We developed and psychometrically evaluated a novel WGS and WES knowledge questionnaire, the Precision in Pediatric Sequencing Knowledge Questionnaire (PIPseqKQ), to identify levels of understanding among parents and young adult cancer survivors (≥ 18 years old), off therapy for at least 1 year from a single-institution pediatric oncology outpatient clinic. Participants also completed health literacy and numeracy questionnaires. All participants provided written informed consent. RESULTS: One hundred eleven participants were enrolled: 76 were parents, and 35 were young adults. Of the total cohort, 77 (69%) were female, 63 (57%) self-identified as white, and 74 (67%) self-identified as non-Hispanic. Sixty-six (59%) had less than a college degree. Adequate health literacy (n = 87; 80%) and numeracy (n = 89; 80%) were demonstrated. Internal consistency was high (Cronbach's α = .88), and test-retest reliability was greater than the 0.7 minimum requirement. Scores were highest for genetic concepts related to health and cancer and lowest for WGS and WES concepts. Health literacy and educational attainment were significantly associated with PIPseqKQ scores. Overall, participants felt the benefits of WGS and WES outweighed the potential risks. CONCLUSION: Parents and young adult cancer survivors have some genetics knowledge, but they lack knowledge about WGS and WES. The PIPseqKQ is a reliable tool that can identify deficits in knowledge, identify perceptions of risks and benefits of WGS and WES, and help clinicians tailor their consent discussions to best fit families. The PIPseqKQ also may inform the development of educational tools to better facilitate the informed consent process in pediatric oncology.

Precision Medicine in Children and Young Adults with Hematologic Malignancies and Blood Disorders: The Columbia University Experience.

BACKGROUND: The advent of comprehensive genomic profiling has markedly advanced the understanding of the biology of pediatric hematological malignancies, however, its application to clinical care is still unclear. We present our experience integrating genomic data into the clinical management of children with high-risk hematologic malignancies and blood disorders and describe the broad impact that genomic profiling has in multiple aspects of patient care. METHODS: The Precision in Pediatric Sequencing Program at Columbia University Medical Center instituted prospective clinical next-generation sequencing (NGS) for high-risk malignancies and blood disorders. Testing included cancer whole exome sequencing (WES) of matched tumor-normal samples or targeted sequencing of 467 cancer-associated genes, when sample adequacy was a concern, and tumor transcriptome (RNA-seq). A multidisciplinary molecular tumor board conducted interpretation of results and final tiered reports were transmitted to the electronic medical record according to patient preferences. RESULTS: Sixty-nine samples from 56 patients with high-risk hematologic malignancies and blood disorders were sequenced. Patients carried diagnoses of myeloid malignancy (n = 25), lymphoid malignancy (n = 25), or histiocytic disorder (n = 6). Six patients had only constitutional WES, performed for a suspicion of an inherited predisposition for their disease. For the remaining 50 patients, tumor was sequenced with matched normal tissue when available. The mean number of somatic variants per sample was low across the different disease categories (2.85 variants/sample). Interestingly, a gene fusion was identified by RNA-seq in 58% of samples who had adequate RNA available for testing. Molecular profiling of tumor tissue led to clinically impactful findings in 90% of patients. Forty patients (80%) had at least one targetable gene variant or fusion identified in their tumor tissue; however, only seven received targeted therapy. Importantly, NGS findings contributed to the refinement of diagnosis and prognosis for 34% of patients. Known or likely pathogenic germline alterations were discovered in 24% of patients involving cancer predisposition genes in 12% of cases. CONCLUSION: Incorporating whole exome and transcriptome profiling of tumor and normal tissue into clinical practice is feasible, and the value that comprehensive testing provides extends beyond the ability to target-specific mutations.

Implementation of next generation sequencing into pediatric hematology-oncology practice: moving beyond actionable alterations.

BACKGROUND: Molecular characterization has the potential to advance the management of pediatric cancer and high-risk hematologic disease. The clinical integration of genome sequencing into standard clinical practice has been limited and the potential utility of genome sequencing to identify clinically impactful information beyond targetable alterations has been underestimated. METHODS: The Precision in Pediatric Sequencing (PIPseq) Program at Columbia University Medical Center instituted prospective clinical next generation sequencing (NGS) for pediatric cancer and hematologic disorders at risk for treatment failure. We performed cancer whole exome sequencing (WES) of patient-matched tumor-normal samples and RNA sequencing (RNA-seq) of tumor to identify sequence variants, fusion transcripts, relative gene expression, and copy number variation (CNV). A directed cancer gene panel assay was used when sample adequacy was a concern. Constitutional WES of patients and parents was performed when a constitutionally encoded disease was suspected. Results were initially reviewed by a molecular pathologist and subsequently by a multi-disciplinary molecular tumor board. Clinical reports were issued to the ordering physician and posted to the patient's electronic medical record. RESULTS: NGS was performed on tumor and/or normal tissue from 101 high-risk pediatric patients. Potentially actionable alterations were identified in 38% of patients, of which only 16% subsequently received matched therapy. In an additional 38% of patients, the genomic data provided clinically relevant information of diagnostic, prognostic, or pharmacogenomic significance. RNA-seq was clinically impactful in 37/65 patients (57%) providing diagnostic and/or prognostic information for 17 patients (26%) and identified therapeutic targets in 15 patients (23%). Known or likely pathogenic germline alterations were discovered in 18/90 patients (20%) with 14% having germline alternations in cancer predisposition genes. American College of Medical Genetics (ACMG) secondary findings were identified in six patients. CONCLUSIONS: Our results demonstrate the feasibility of incorporating clinical NGS into pediatric hematology-oncology practice. Beyond the identification of actionable alterations, the ability to avoid ineffective/inappropriate therapies, make a definitive diagnosis, and identify pharmacogenomic modifiers is clinically impactful. Taking a more inclusive view of potential clinical utility, 66% of cases tested through our program had clinically impactful findings and samples interrogated with both WES and RNA-seq resulted in data that impacted clinical decisions in 75% of cases.

Overcoming challenges to meaningful informed consent for whole genome sequencing in pediatric cancer research.

BACKGROUND: Introducing whole genome sequencing (WGS) into pediatric cancer research at diagnosis poses unique challenges related to informed consent. WGS requires tissue obtained prior to initiating treatment, when families may be overwhelmed with uncertainty and fear. Motivation to participate may be high without fully understanding the range of possible results, including secondary findings. Little is known about parental knowledge, attitudes, and beliefs about this type of research. PROCEDURE: A qualitative study was conducted to investigate parental knowledge about genetic concepts and WGS, thoughts about the informed consent process, and preferences for secondary findings. Focus groups were conducted with parents/guardians of children with cancer and semi-structured interviews were conducted in a control group without cancer. All transcripts were analyzed using content analysis. RESULTS: Four focus groups included 15 participants; eight semi-structured interviews included 10 participants. Basic knowledge about genetics was limited to heredity. Some knowledge of genomic analysis was present in 3/15 focus group participants. Major factors related to participation in WGS research were: (i) hope for their child and future children; (ii) no additional procedures; (iii) and protection of privacy. All favored a two-step consent process, first to store extra tissue from a diagnostic biopsy/resection, followed by consenting to WGS research, one-to-two months later. The desire to receive secondary findings was high among both groups, but there were individuals who did not want these results, fearing increased anxiety. CONCLUSIONS: Parents/guardians of children with cancer have limited knowledge about WGS. A two-step consent process may improve their ability to provide meaningful informed consent.

Clinical outcomes and late endocrine, neurocognitive, and visual profiles of proton radiation for pediatric low-grade gliomas.

PURPOSE/OBJECTIVE(S): Primary low-grade gliomas are common brain tumors of childhood, many of which require radiation therapy (RT) as definitive treatment. Increased conformality of RT could decrease the incidence and severity of late effects. We report our experience with 32 pediatric patients treated with proton RT. METHODS AND MATERIALS: Thirty-two pediatric patients with low-grade gliomas of the brain or spinal cord were treated with proton RT from 1995 to 2007. Sixteen patients received at least 1 regimen of chemotherapy before definitive RT. The median radiation dose was 52.2 GyRBE (48.6-54 GyRBE). RESULTS: The median age at treatment was 11.0 years (range, 2.7-21.5 years), with a median follow-up time of 7.6 years (range, 3.2-18.2 years). The 6-year and 8-year rates of progression-free survival were 89.7% and 82.8%, respectively, with an 8-year overall survival of 100%. For the subset of patients who received serial neurocognitive testing, there were no significant declines in Full-Scale Intelligence Quotient (P=.80), with a median neurocognitive testing interval of 4.5 years (range, 1.2-8.1 years) from baseline to follow-up, but subgroup analysis indicated some significant decline in neurocognitive outcomes for young children (<7 years) and those with significant dose to the left temporal lobe/hippocampus. The incidence of endocrinopathy correlated with a mean dose of ≥40 GyRBE to the hypothalamus, pituitary, or optic chiasm. Stabilization or improvement of visual acuity was achieved in 83.3% of patients at risk for radiation-induced injury to the optic pathways. CONCLUSIONS: This report of late effects in children with low-grade gliomas after proton RT is encouraging. Proton RT appears to be associated with good clinical outcome, especially when the tumor location allows for increased sparing of the left temporal lobe, hippocampus, and hypothalamic-pituitary axis.

Neurocognitive functioning and quality of life in patients with recurrent malignant gliomas treated on a phase Ib trial evaluating topotecan by convection-enhanced delivery.

BACKGROUND: Malignant gliomas are highly proliferative, invasive tumors that are resistant to conventional treatment, and disease progression is often accompanied by physical and mental debilitation. Neurocognitive functioning (NCF) and quality of life (QoL) were evaluated as part of a prospective phase Ib dose-escalation study of topotecan by convection-enhanced delivery (CED) for adult patients with recurrent malignant gliomas. METHODS: Sixteen patients were enrolled, and NCF and QoL were evaluated using the Cognitive Stability Index and SF-36 at baseline and monthly for 4 months post treatment. Descriptive analyses included the reliable change index for serial evaluations and correlations for associations between outcome variables and age, tumor volume, total topotecan dose, and treatment effect. RESULTS: Individual classifications of response to treatment indicated that a majority of patients reported stable scores over the follow-up period. Demographic and treatment-related variables were not associated with outcomes. Baseline processing speed scores were invalid for 6 subjects. Higher rates of valid scores were observed on subsequent administrations. CONCLUSIONS: As the first study to use CED of any kind to evaluate the impact of CED on NCF or QoL, there was no evidence of severe detriment to either outcome. Long-term evaluation is necessary to track changes in NCF and QoL related to disease progression. Invalid scores suggest that computer-based assessments may not be suitable for all patients with malignant gliomas, especially those with cognitive deficits secondary to their disease. Future trials should include a wider range of sensitive measures to assess the impact of CED on patient NCF and QoL.

Deregulation of Rab5 and Rab4 proteins in p85R274A-expressing cells alters PDGFR trafficking.

Activated receptor tyrosine kinases recruit many signaling proteins to activate downstream cell proliferation and survival pathways, including phosphatidylinositol 3-kinase (PI3K) consisting of a p85 regulatory protein and a p110 catalytic protein. We have recently shown the p85alpha protein also has in vitro GTPase activating protein (GAP) activity towards Rab5 and Rab4, small GTPases that regulate vesicle trafficking events for activated receptors. Expression of a GAP-defective mutant, p85R274A, resulted in sustained levels of activated platelet-derived growth factor receptors (PDGFRs) and enhanced downstream signaling. In this report we have characterized Rab5- and Rab4-mediated PDGFR trafficking in cells expressing wild type p85 and GAP-defective mutant p85R274A. Wild type p85 overexpressing cells had slower PDGFR trafficking consistent with enhanced GAP activity deactivating Rab5 and Rab4 to block their vesicle trafficking functions. Mutant p85R274A expression increased the internalization rate of PDGFRs, a Rab5-dependent process, without preventing PDGFR ubiquitination. Immunofluorescence studies further demonstrated that p85R274A-expressing cells showed Rab5 accumulation at intracellular locations. Pull-down and FRAP (fluorescence recovery after photobleaching) experiments indicate this is likely membrane-associated Rab5-GTP, sustained due to decreased p85 GAP activity for the p85R274A mutant. These cells also had substantial amounts of activated PDGFRs in Rab4-positive recycling endosomes, a compartment that usually contains primarily deactivated/dephosphorylated receptors. Our results suggest that the PDGFR-associated GAP activity of p85 regulates both Rab5 and Rab4 functions in cells to influence the movement of activated PDGFR through endosomal compartments. Disruption of this regulation by p85R274A expression impacts PDGFR phosphorylation/dephosphorylation, degradation kinetics and downstream signaling by altering the time receptors spend in specific intracellular endosomal compartments. These results demonstrate that the p85alpha protein is an important regulator of Rab-mediated PDGFR trafficking, which significantly impacts receptor signaling and degradation.

Neuropsychological functioning of children treated with intensive chemotherapy followed by myeloablative consolidation chemotherapy and autologous hematopoietic cell rescue for newly diagnosed CNS tumors: an analysis of the Head Start II survivors.

BACKGROUND: To evaluate the neuropsychological late effects amongst survivors treated on the Head Start II protocol between 1997 and 2003. PROCEDURES: Forty-nine patients (mean age 2.9 years) diagnosed with a malignant brain tumor underwent baseline neuropsychological assessment prior to autologous hematopoietic cell transplantation (AuHCT). Twenty-six survivors were retested after 3 years of follow-up as 20 patients did not survive. Patients were evaluated for intelligence, academic achievement, receptive language, visual-motor integration (VMI), learning/memory, social-emotional and behavioral functioning based upon age at testing. RESULTS: Overall intelligence and VMI at baseline were low average while verbal and non-verbal intelligence, academic achievement, and receptive vocabulary were in average range. Parents reported social-emotional and behavioral functioning within normal limits. Serial testing revealed Full Scale (FSIQ)/Mental Development Index (MDI), Verbal (VIQ), and Performance (PIQ) Intelligence to be generally stable over 3-year follow-up. Group-average analysis at follow-up demonstrated low average intelligence, academic achievement, receptive language, and VMI. Age at diagnosis was positively correlated with internalizing symptoms and visual immediate memory, while time since diagnosis was inversely correlated with FSIQ, VIQ, PIQ, reading and delayed verbal memory. Craniospinal irradiation (CSI) was avoided in two-thirds of patients. CONCLUSION: Induction, with or without intensification using intravenous methotrexate, followed by myeloablative consolidation chemotherapy with AuHCT, may avoid or delay CSI, with possible stabilization of neuropsychological functioning, including those younger at diagnosis. Continued follow-up is necessary to determine the preservation of neuropsychological, academic, social-emotional and behavioral functioning.

Disrupted RabGAP function of the p85 subunit of phosphatidylinositol 3-kinase results in cell transformation.

Rab proteins regulate vesicle fusion events during the endocytosis, recycling, and degradation of activated receptor tyrosine kinases. The p85alpha subunit of phosphatidylinositol 3-kinase has GTPase-activating protein activity toward Rab5 and Rab4, an activity severely reduced by a single point mutation (p85-R274A). Expression of p85-R274A resulted in increased platelet-derived growth factor receptor (PDGFR) activation and downstream signaling (Akt and MAPK) and in decreased PDGFR degradation. We now report that the biological consequences of p85-R274A expression cause cellular transformation as determined by the following: aberrant morphological phenotype, loss of contact inhibition, growth in soft agar, and tumor formation in nude mice. Immunohistochemistry shows that the tumors contain activated PDGFR and high levels of activated Akt. Coexpression of a dominant negative Rab5-S34N mutant attenuated these transformed properties. Our results demonstrate that disruption of the RabGAP function of p85alpha due to a single point mutation (R274A) is sufficient to cause cellular transformation via a phosphatidylinositol 3-kinase-independent mechanism partially reversed by Rab5-S34N expression. This critical new role for p85 in the regulation of Rab function suggests a novel role for p85 in controlling receptor signaling and trafficking through its effects on Rab GTPases.