A Validated Highly Sensitive Microsatellite Instability Assay Accurately Identifies Individuals Harboring Biallelic Germline PMS2 Pathogenic Variants in Constitutional Mismatch Repair Deficiency.

BACKGROUND: Constitutional mismatch repair deficiency (CMMRD) is a rare and extraordinarily penetrant childhood-onset cancer predisposition syndrome. Genetic diagnosis is often hampered by the identification of mismatch repair (MMR) variants of unknown significance and difficulties in PMS2 analysis, the most frequently mutated gene in CMMRD. We present the validation of a robust functional tool for CMMRD diagnosis and the characterization of microsatellite instability (MSI) patterns in blood and tumors. METHODS: The highly sensitive assessment of MSI (hs-MSI) was tested on a blinded cohort of 66 blood samples and 24 CMMRD tumor samples. Hs-MSI scores were compared with low-pass genomic instability scores (LOGIC/MMRDness). The correlation of hs-MSI scores in blood with age of cancer onset and the distribution of insertion-deletion (indel) variants in microsatellites were analyzed in a series of 169 individuals (n = 68 CMMRD, n = 124 non-CMMRD). RESULTS: Hs-MSI achieved high accuracy in the identification of CMMRD in blood (sensitivity 98.5% and specificity 100%) and detected MSI in CMMRD-associated tumors. Hs-MSI had a strong positive correlation with whole low-pass genomic instability LOGIC scores (r = 0.89, P = 2.2e-15 in blood and r = 0.82, P = 7e-3 in tumors). Indel distribution identified PMS2 pathogenic variant (PV) carriers from other biallelic MMR gene PV carriers with an accuracy of 0.997. Higher hs-MSI scores correlated with younger age at diagnosis of the first tumor (r = -0.43, P = 0.011). CONCLUSIONS: Our study confirms the accuracy of the hs-MSI assay as ancillary testing for CMMRD diagnosis, which can also characterize MSI patterns in CMMRD-associated cancers. Hs-MSI is a powerful tool to pinpoint PMS2 as the affected germline gene and thus potentially personalize cancer risk.

Decreased Fatty Acid Oxidation Gene Expression in Pre-Eclampsia According to the Onset and Presence of Intrauterine Growth Restriction.

Mitochondrial fatty acid oxidation (FAO) is lower in placentas with pre-eclampsia. The aim of our study was to compare the placental mRNA expression of FAO enzymes in healthy pregnancies vs. different subgroups of pre-eclampsia according to the severity, time of onset, and the presence of intrauterine growth restriction (IUGR). By using real-time qPCR, we measured the mRNA levels of long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD), medium-chain acyl-CoA dehydrogenase (MCAD), and carnitine palmitoyltransferases 1A and 2 (CPT1A, CPT2) on the maternal side (anchoring villi in the basal decidua) and on the fetal side (chorionic plate) of the placenta (n = 56). When compared to the controls, LCHAD, MCAD, and CPT2 mRNA had decreased in all pre-eclampsia subgroups globally and on the fetal side. On the maternal side, LCHAD mRNA was also lower in all pre-eclampsia subgroups; however, MCAD and CPT2 mRNA were only reduced in severe and early-onset disease, as well as CPT2 in IUGR (p < 0.05). There were no differences in CPT1A mRNA expression. We conclude that the FAO enzymes mRNA in the placenta was lower in pre-eclampsia, with higher reductions observed in severe, early-onset, and IUGR cases and more striking reductions on the fetal side.

How a pediatric neuro-oncology unit was managed in Madrid during the first wave of the COVID-19 pandemic.

INTRODUCTION: During the first wave of the coronavirus disease 2019 (COVID-19) pandemic, infection prevention measures were enforced at our Pediatric Neuro-Oncology unit. METHODS: A retrospective study analyzing patients booked in this unit during lockdown was performed to describe its performance. RESULTS: There were 438 consultations for 123 patients (320 on-site/118 telephone). Eight new diagnoses were made, with one significant delay. Only one patient tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Delay in imaging testing occurred in 15 patients. Chemotherapy was delayed in one case. There were no delays in radiotherapy. CONCLUSIONS: Measures implemented were effective in minimizing the risk of COVID-19 infection, achieving continuity in diagnoses and treatment, and avoiding delays that could impact survival.

The Relationship between Angiogenic Factors and Energy Metabolism in Preeclampsia.

Antiangiogenic factors are currently used for the prediction of preeclampsia. The present study aimed to evaluate the relationship between antiangiogenic factors and lipid and carbohydrate metabolism in maternal plasma and placenta. We analyzed 56 pregnant women, 30 healthy and 26 with preeclampsia (including early and late onset). We compared antiangiogenic factors soluble Fms-like Tyrosine Kinase-1 (sfLt-1), placental growth factor (PlGF), and soluble endoglin (sEng)), lipid and carbohydrate metabolism in maternal plasma, and lipid metabolism in the placenta from assays of fatty acid oxidation, fatty acid esterification, and triglyceride levels in all groups. Antiangiogenic factors sFlt-1, sFlt-1/PlGF ratio, and sEng showed a positive correlation with triglyceride, free fatty acid, and C-peptide maternal serum levels. However, there was no relationship between angiogenic factors and placental lipid metabolism parameters. Free fatty acids were predictive of elevated sFlt-1 and sEng, while C-peptide was predictive of an elevated sFlt1/PlGF ratio. The findings in this study generate a model to predict elevated antiangiogenic factor values and the relationship between them with different products of lipid and carbohydrate metabolism in maternal serum and placenta in preeclampsia.

[Wilms' tumour: A review of 15 years recent experience]. / Tumor de Wilms: revisión de nuestra experiencia en los últimos 15 años.

INTRODUCTION: Wilms' tumour is the most frequent renal tumour in children. Multi-modal treatment includes chemotherapy and surgery, with or without radiotherapy. The survival is excellent, with rates exceeding 90%. A review is presented on our experience over the last 15 years of treating Wilms' tumour in Hospital Niño Jesús, Madrid. PATIENTS AND METHODS: A retrospective study was conducted on 40 consecutive paediatric patients diagnosed with nephroblastoma between 2002 and 2016 in the Hospital Niño Jesús in Madrid. The clinical characteristics, diagnostic methods, treatment, and follow-up were analysed. RESULTS: Of the 40 patients, 23 were boys, with a median age at diagnosis of 2.5 years (range, 4 months-15 years). Three patients underwent initial nephrectomy, three received a fine needle aspiration biopsy, followed by chemotherapy, and 34 patients started pre-operative chemotherapy directly. The median follow-up of the patients was 6.75 years (range, 10 months - 13.92 years). Two patients died from disease progression. There were no treatment-related deaths. Overall survival and event-free survival at 5 years was 94.6±3.7% and 89.4±5%, respectively. CONCLUSION: Wilms' tumour treatment is a success of modern medicine, currently achieving a survival rate of 95% in our series.

Medulloblastoma in children and adolescents: a systematic review of contemporary phase I and II clinical trials and biology update.

Survival rates for patients with medulloblastoma have improved in the last decades but for those who relapse outcome is dismal and new approaches are needed. Emerging drugs have been tested in the last two decades within the context of phase I/II trials. In parallel, advances in genetic profiling have permitted to identify key molecular alterations for which new strategies are being developed. We performed a systematic review focused on the design and outcome of early-phase trials evaluating new agents in patients with relapsed medulloblastoma. PubMed, clinicaltrials.gov, and references from selected studies were screened to identify phase I/II studies with reported results between 2000 and 2015 including patients with medulloblastoma aged <18 years. A total of 718 studies were reviewed and 78 satisfied eligibility criteria. Of those, 69% were phase I; 31% phase II. Half evaluated conventional chemotherapeutics and 35% targeted agents. Overall, 662 patients with medulloblastoma/primitive neuroectodermal tumors were included. The study designs and the response assessments were heterogeneous, limiting the comparisons among trials and the correct identification of active drugs. Median (range) objective response rate (ORR) for patients with medulloblastoma in phase I/II studies was 0% (0-100) and 6.5% (0-50), respectively. Temozolomide containing regimens had a median ORR of 16.5% (0-100). Smoothened inhibitors trials had a median ORR of 8% (3-8). Novel drugs have shown limited activity against relapsed medulloblastoma. Temozolomide might serve as backbone for new combinations. Novel and more homogenous trial designs might facilitate the development of new drugs.

Dicentric translocation (9;12) in acute lymphoblastic leukemia: a chromosomal abnormality with an excellent prognosis?

PURPOSE: Recurrent chromosomal abnormalities present in the leukemic cells of pediatric patients with acute lymphoblastic leukemia (ALL) often allow us to classify patients according to their prognosis, in order to establish further treatment. The dicentric translocation (9;12) consists of the rearrangement of the short arms of chromosomes 9 and 12 generating a dicentric chromosome (9;12). Patients with this alteration present a very good response to treatment and an excellent prognosis. METHODS: We present the case of an adolescent with ALL in which the dicentric translocation (9;12) was observed in the karyotype of the blasts at diagnosis. RESULTS AND CONCLUSION: Given the excellent results of our patient and most of the series published to date, an international study is necessary to determine the true prognostic significance of this molecular alteration.