A Case of Dubin-Johnson Syndrome Presenting as Neonatal Cholestasis With Paucity of Interlobular Bile Ducts.

Dubin-Johnson syndrome (DJS) is a rare autosomal recessive disorder that typically manifests in young adulthood as jaundice with conjugated hyperbilirubinemia. We report a case presenting as neonatal cholestasis with the unexpected histologic finding of paucity of interlobular bile ducts, a feature that is not typically seen in DJS. The diagnosis was confirmed by absent canalicular multidrug-resistance-associated protein 2 (MRP2) immunohistochemical staining on liver biopsy tissue and molecular genetic testing that demonstrated heterozygous mutations in the ATP-Binding Cassette Subfamily C Member 2 (ABCC2) gene, including a novel missense mutation. This report describes a case of DJS with atypical clinicopathologic findings and suggests that DJS should be considered in patients with neonatal cholestasis and bile duct paucity.

Application of 2016 WHO classification in the diagnosis of paediatric high-grade MYC-negative mature B-cell lymphoma with Burkitt-like morphological features.

AIMS: Historically, there has been no consensus on the diagnostic classification of high-grade B-cell lymphoma (HGBCL) with morphological features of Burkitt lymphoma (BL) but no MYC gene rearrangement (MYC-negative). The 2016 WHO classification of tumours of haematopoietic and lymphoid tissues has shed some light on this field with the modification of the grey-zone lymphoma with features intermediate between BL and diffuse large B-cell lymphoma, and the creation of several new entities. The aim of this study was to investigate how the revised WHO classification affects our practice in diagnosing these lymphomas in children. METHODS: We retrospectively reviewed cases of mature HGBCL diagnosed at our hospital between 2015 and 2018. RESULTS: Among 14 mature HGBCL cases with BL morphological features, 11 showed MYC rearrangement consistent with BL and 3 were MYC-negative. Two MYC-negative cases showed regions of 11q gain and loss by microarray consistent with Burkitt-like lymphoma with 11q aberration (BLL-11q). The third MYC-negative case showed diffuse and strong MUM1 expression, translocation involving 6p25 by chromosome analysis and IRF4 rearrangement by fluorescence in situ hybridisation analysis consistent with large B-cell lymphoma with IRF4 rearrangement (LBL-IRF4). All patients were treated according to applicable chemotherapeutic protocols and achieved remission. CONCLUSIONS: BLL-11q and LBL-IRF4, two newly defined entities, should be considered in paediatric MYC-negative mature HGBCL cases. Accurate diagnosis needs careful histopathological examination and proper cytogenetic testing. Since they have unique cytogenetic features, specific treatments for them may emerge in the future. Therefore, accurate diagnosis based on the 2016 WHO classification is clinically significant.

Noonan Syndrome Case Report: PTPN11 and Other Potential Genetic Factors Contributing to Lethal Hypertrophic Right Ventricular Cardiomyopathy.

Noonan syndrome is a genetic condition with a heterogeneous phenotype and multisystem involvement. The pathogenesis of this disorder has been attributed to the mutations in the RAS/MAPK signaling pathway involved in cell proliferation and differentiation. The most common clinical presentations are related to cardiovascular abnormalities with congestive heart failure as the most common mechanism of death. We present the autopsy findings from a Noonan syndrome patient who died as a result of an unusual form of right ventricular obstruction associated with a rare PTPN11 variant previously reported without details of the cardiac findings. Discussion follows that includes overview of the incidence, genetic causes, types of right-sided obstructive lesions, PTPN11 genotype-cardiac phenotype correlations, and other potential mechanisms that may contribute to disease heterogeneity.

A patient with polymerase E1 deficiency (POLE1): clinical features and overlap with DNA breakage/instability syndromes.

BACKGROUND: Chromosome instability syndromes are a group of inherited conditions associated with chromosomal instability and breakage, often leading to immunodeficiency, growth retardation and increased risk of malignancy. CASE PRESENTATION: We performed exome sequencing on a girl with a suspected chromosome instability syndrome that manifested as growth retardation, microcephaly, developmental delay, dysmorphic features, poikiloderma, immune deficiency with pancytopenia, and myelodysplasia. She was homozygous for a previously reported splice variant, c.4444 + 3A > G in the POLE1 gene, which encodes the catalytic subunit of DNA polymerase E. CONCLUSION: This is the second family with POLE1-deficency, with the affected individual demonstrating a more severe phenotype than previously described.

Spitzoid melanoma in a child with Li-Fraumeni syndrome.

Spitzoid melanoma of childhood is a rare malignancy. The histological features are at the upper end of a range encompassing Spitz nevus and atypical Spitz tumor, the unifying features including large oval, fusiform or polygonal melanocytes with abundant homogeneous-appearing cytoplasma and large vesicular nuclei. The presence of a "bottom-heavy" pattern, strikingly enlarged nuclei and nucleoli in both the upper and lower portions of the lesion, and deep mitotic figures are among the findings that distinguish most of the Spitzoid melanomas from Spitz nevi and atypical Spitz tumors. There are no syndromic associations reported for this malignancy. We report the occurrence of choroid plexus carcinoma, Spitzoid melanoma, and myelodysplasia in a child who was found to carry a germline mutation for TP53. While choroid plexus carcinoma and myelodysplasia have relatively frequently been described, melanomas have been very rarely described in Li-Fraumeni syndrome. The association of Spitzoid melanoma with Li-Fraumeni syndrome, especially in a pediatric patient, has not been reported before.

Molecular diagnosis of infantile onset inflammatory bowel disease by exome sequencing.

Pediatric-onset inflammatory bowel disease (IBD) is known to be associated with severe disease, poor response to therapy, and increased morbidity and mortality. We conducted exome sequencing of two brothers from a non-consanguineous relationship who presented before the age of one with severe infantile-onset IBD, failure to thrive, skin rash, and perirectal abscesses refractory to medical management. We examined the variants discovered in all known IBD-associated and primary immunodeficiency genes in both siblings. The siblings were identified to harbor compound heterozygous mutations in IL10RA (c.784C>T, p.Arg262Cys; c.349C>T, p.Arg117Cys). Upon molecular diagnosis, the proband underwent successful hematopoietic stem cell transplantation and demonstrated marked clinical improvement of all IBD-associated clinical symptoms. Exome sequencing can be an effective tool to aid in the molecular diagnosis of pediatric-onset IBD. We provide additional evidence of the safety and benefit of HSCT for patients with IBD due to mutations in the IL10RA gene.

Hb Lake Tapawingo [α46(CE4)Phe→Ser; HBA2:c.140T>C]: a new unstable α chain hemoglobin variant associated with low systemic arterial saturation.

A new unstable α-globin variant was detected in a child with hypoxemia and anemia. The child's mother was found to carry the same mutation. The hemoglobin (Hb) variant co-eluted with Hb A(2) by cation exchange high performance liquid chromatography (HPLC) and appeared cathodal to Hb A and anodal to Hb F by isoelectric focusing. It represented less than 20% of the total Hb and was unstable by isopropanol testing. Gene sequencing identified a missense mutation on the α2 gene [HBA2:c.140T>C]. Oxygen dissociation and P(50) test results were normal.

Haploinsufficiencies of FOXF1 and FOXC2 genes associated with lethal alveolar capillary dysplasia and congenital heart disease.

Neonatal deaths account for about 67% of all deaths during the first year of life in the USA. Genetic defects are important factors contributing to neonatal deaths and congenital anomalies. Here we report on the identification of a 1.37 Mb de novo deletion of chromosome 16q24.1-q24.2 by microarray-based comparative genomic hybridization (aCGH) technique in a newborn boy with lethal severe alveolar capillary dysplasia and multiple congenital anomalies who died of irreversible pulmonary hypertension, respiratory failure and cor pulmonale at three days of age. The phenotypic findings and causal genes (FOXF1 and FOXC2) involved in producing this unusual syndrome are detailed. Our findings independently confirm the results in a previous publication describing multiple patients with similar clinical and genetic observations, and highlight the importance of scanning human genomes at high resolution for identifications of micro-imbalances as pathogenic causes in neonates with unexplained congenital anomalies. (c) 2010 Wiley-Liss, Inc.

Validation of the Agilent 244K oligonucleotide array-based comparative genomic hybridization platform for clinical cytogenetic diagnosis.

High-resolution microarray comparative genomic hybridization (aCGH) is being adopted for diagnostic evaluation of genomic disorders, but validation for clinical diagnosis has not yet been reported. We present validation data for the Agilent Human Genome Microarray Kit 244K for clinical application. The platform contains approximately 240,000 distinct 60-mer oligonucleotide probes spanning the entire human genome. We studied 45 previously characterized samples (43 abnormal, 2 normal), 32 with knowledge of prior results and 13 in a blinded manner with 11 performed in a reference laboratory providing microarray testing. Array analysis confirmed known aberrations in 43 samples and a normal result in 2. The array analysis corrected 1 karyotype and clarified 2 additional cases. Array data from 6 patients with 22q11.2 deletion found an average of 2.56 megabases (Mb; range, 2.49-2.62 Mb) with a common 2.43-Mb deleted region. Approximately 7 copy number variants from 400 base pairs to 1.6 Mb were identified per sample. Results demonstrate the usefulness of the aCGH-244K platform as a powerful diagnostic tool.

Intensive chemotherapy for systemic anaplastic large cell lymphoma in children and adolescents: final results of Children's Cancer Group Study 5941.

BACKGROUND: Anaplastic large cell lymphoma (ALCL) is characterized by advanced disease at presentation (70-80% of pediatric cases) and accounts for 10-15% of all childhood lymphomas. Treatment strategies for pediatric ALCL vary from short pulse B-NHL chemotherapy to prolonged leukemia like therapy. The optimal treatment strategy is unknown. METHODS: CCG-5941 used a compressed aggressive multiagent T-cell lineage chemotherapy regimen consisting of a 3-week induction therapy (vincristine, prednisone, cyclophosphamide, daunomycin, asparaginase) followed by a 3-week consolidation period (vincristine, prednisone, etoposide, 6-thioguanine, cytarabine, asparaginase, methotrexate) followed by six courses of maintenance chemotherapy at 7-week intervals (cyclophosphamide, 6-thioguanine, vincristine, prednisone, doxorubicin, asparaginase, methotrexate etoposide, cytarabine). Total therapy was 48 weeks. RESULTS: Eighty-six children (male 56%, female 44%) with non-localized ALCL (CD30+) were treated. The majority of tumors were positive for ALK (90%) and of T lineage (83%). Extranodal disease was common (mediastinum 35%, skin 15%, lung 14%, bone 12%, bone marrow 13%, liver 6%, and other viscera 17%). Grade 4 neutropenia occurred in 82% of patients. The 5-year EFS was 68% (95% CI of 57-78%) and the 5-year OS was 80% (95% CI of 69-87%). There were 21 relapses and 4 toxic deaths as first events. Relapse occurred early with 17 (81%) relapses occurring within 2 years of diagnosis and 12 (57%) while receiving therapy. Univariate analysis for risk factors only identified bone marrow involvement predicting lower EFS (P = 0.03). CONCLUSIONS: CCG-5941 demonstrated efficacy similar to previously reported regimens but with significant hematologic toxicity.

Shortened intensified multi-agent chemotherapy and non-cross resistant maintenance therapy for advanced lymphoblastic lymphoma in children and adolescents: report from the Children's Oncology Group.

Pediatric lymphoblastic lymphoma (LL) has utilized treatment strategies similar to childhood acute lymphoblastic leukaemia (ALL) with prolonged maintenance chemotherapy. We report the results of a pilot study to estimate the feasibility, toxicity and efficacy of a 12-month aggressive multi-agent chemotherapy regimen in children and adolescents with advanced LL. Between July 1994 and June 1997, 85 eligible children and adolescents with advanced LL (Stage III/IV) were enrolled on this pilot study. Patients achieving a complete response following induction and consolidation received six cycles of maintenance chemotherapy for a total duration of 12 months. Grade III/IV toxicities included: hematological (80%), infections (20%), stomatitis and elevated transaminases, (29%). There were a total of 19 events, 13 relapses, two secondary acute myeloid leukaemia and four toxic deaths (5%). The 5-year event-free survival (EFS) and overall survival (OS) was 78 +/- 4.5% and 85 +/- 3.9%, respectively. Relapsed patients had a 5-year OS of only 33 +/- 14%. Multivariate analysis failed to demonstrate age, gender, lactate dehydrogenase level, presence of marrow and/or central nervous system disease to have independent prognostic value. These results suggest that this experimental approach is safe and results in similar outcomes as more prolonged childhood ALL regimens.

Immunophenotypic identification of possible therapeutic targets in paediatric non-Hodgkin lymphomas: a children's oncology group report.

Immunophenotypic analysis can identify protein epitopes in non-Hodgkin lymphomas (NHL) that may respond to targeted immunotherapies, such as anti-CD20 and anti-CD52. Recent studies suggest additional targets may provide therapeutic benefits in NHL. This study evaluated protein expression of CD25, CD52, CD74 and CD80 in paediatric NHL to determine possible targets for immune-based therapeutic approaches. Patient samples were derived from paediatric NHL clinical trials sponsored by the Children's Cancer Group (CCG, now the Children's Oncology Group, COG) and included Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL), disseminated T- and B-cell lymphoblastic lymphoma (T-LBL and B-LBL) and anaplastic large cell (ALCL). Immunophenotypic studies were performed on formalin-fixed, paraffin-embedded diagnostic tissues. CD25 was expressed in 8% of T-LBL and 75% of ALCL cases, but not in BL, DLBCL, or B-LBL. CD52 was expressed in 99% of cases of paediatric NHL of all subtypes. CD74 was expressed in 100% of B-LBL, BL and DLBCL, but was absent in ALCL and T-LBL. CD80 was expressed in 12% of B-LBL, 6% of BL and 10% of DLBCL cases studied, but was not detected in T-cell NHL. These expression patterns suggest that CD25, CD52 and CD74 may represent potential new therapeutic targets in paediatric NHL.

Minimal residual disease testing of acute leukemia by flow cytometry immunophenotyping: a retrospective comparison of detection rates with flow cytometry DNA ploidy or FISH-based methods.

The detection and quantification of minimal residual leukemia (MRD) has importance for monitoring continued disease response and detection of early relapse. We retrospectively compared MRD detection rates and percentages of residual leukemia by flow cytometry immunophenotyping (FCIP) with results obtained by either flow cytometry DNA (FCDNA) ploidy (n = 14) and/or fluorescent in situ hybridization (FISH) (n = 33) testing for cases with 1.5% or less residual leukemia. A total of 42 paired results were obtained from 20 pediatric patients, including 16 with B lineage acute lymphocytic leukemia and 4 patients with acute myeloid leukemia during the course of induction and/or relapse. Eighty-one percent of the results were concordant (20 negative and 14 positive). There was reasonable correlation coefficients for quantity of residual disease by FCIP and FCDNA ploidy, and poor correlation coefficients for levels of residual disease between FCIP- and FISH-based results. FCIP MRD sensitivity and specificity was 78% and 83%, respectively. Factors contributing to the 19% discordant rate include low sensitivity of the DNA-based methods as applied and antigenic modulation of immunophenotype during the course of treatment. There is a reasonable agreement between the FCIP and FCDNA or FISH methods for detecting and quantifying MRD. However, the methods are viewed as complementary with their own inherent limitations.

Successful treatment of pulmonary zygomycosis with posaconazole in a recipient of a haploidentical donor stem cell transplant.

We report the clinical course of a patient who developed a Rhizopus infection of his right lung and pleural cavity, 11 months after receiving a T-cell-depleted, haploidentical donor peripheral blood stem cell transplant. Thoracotomy was performed to remove the pulmonary lesion, but residual disease in the pleural cavity was noted. Treatment with amphotericin B was complicated by the development of severe renal dysfunction, necessitating alternative antifungal therapy. Treatment was initiated with the investigational triazole posaconazole. Despite concurrent treatment with corticosteroids for graft-versus-host disease (GVHD), the patient had a complete response and remains well 4 years later.

Childhood anaplastic large cell lymphoma has a high incidence of ALK gene rearrangement as determined by immunohistochemical staining and fluorescent in situ hybridisation: a genetic and pathological correlation.

Anaplastic large cell lymphoma (ALCL) comprises 10-15% of childhood non-Hodgkin lymphomas (NHL). Systemic ALCL is highly associated with anaplastic lymphoma kinase (ALK) gene translocations with over-expression of ALK protein. We studied ALK rearrangements using fluorescence in situ hybridisation (FISH) and ALK immunohistochemical staining in 43 paediatric systemic ALCLs. FISH (performed on 35 cases) identified a translocation in 29 cases (83%). Immunohistochemistry identified ALK over-expression in 42/43 cases (97%) with the single ALK-negative case demonstrating an ALK rearrangement by FISH, indicating 100% incidence of ALK translocations.

Malassezia furfur meningitis associated with total parenteral nutrition subdural effusion.

We present a case of Malassezia furfur meningitis arising in a very low birth weight infant with chronic lung disease, necrotizing enterocolitis, and intraventricular hemorrhage. M. furfur meningitis was probably acquired late following successful treatment for earlier systemic central line-associated M. furfur infection. M. furfur meningitis has only once been previously reported. Unlike the previous case where meningitis was secondary to widespread blood-borne dissemination, infection was limited to the leptomeninges and arose in association with extravasation of total parenteral nutrition (TPN) and intralipid fluid into subarachnoid space via peripheral scalp catheter.

Non-Hodgkin's lymphoma arising in bone in children and adolescents is associated with an excellent outcome: a Children's Cancer Group report.

PURPOSE: Non-Hodgkin's lymphoma (NHL) arising in bone is a heterogeneous histologic type of NHL that includes large-cell lymphoma, lymphoblastic lymphoma, and small noncleaved-cell lymphoma. NHL arising in bone is well recognized in adults but is less well characterized and infrequent in children and adolescents. PATIENTS AND METHODS: We performed a retrospective review of Children's Cancer Group (CCG) studies treating children and adolescents with NHL over a 20-year period (CCG-551, CCG-501, CCG-502, CCG-503, CCG-552, CCG-5911, and CCG-5941) and determined the response and event-free survival (EFS) rates in 31 patients with NHL arising in bone. RESULTS: The patients ranged in age from 3 to 17 years (median, 11 years; mean, 11 years), and 64.5% were male. All 31 (100%) patients achieved complete response. For 31 patients with NHL arising in bone, the product-limit estimated 5-year EFS was 83.8% +/- 6.7%. EFS in 17 patients with localized disease (Murphy stages I and II) was 94.1% +/- 5.7%, and EFS in 14 patients with disseminated disease (Murphy stage III) was 70.7% +/- 12.4% (log-rank P =.10). EFS in 17 patients treated with chemotherapy and radiation was 70.1% +/- 11.2%, and EFS in 14 patients treated with chemotherapy without radiation was 100% (P =.03). EFS in 26 patients with histology-directed treatment (LSA2-L2 or ADCOMP for lymphoblastic, other therapy for nonlymphoblastic) was 92.2% +/- 5.3%, and in five patients with nonhistology-directed treatment it was 40.0% +/- 21.9% (P <.001). CONCLUSION: NHL arising in bone is a heterogeneous type of NHL that makes up approximately 2.0% of NHL in children and adolescents on CCG studies. Response and survival in this young age group seem superb, with histology-directed treatment protocols without radiation in both localized and disseminated disease.