Genetic Variants Influence the Severity of Oral Mucositis in Pediatric Osteosarcoma Patients.

Background: The variability in patients' risk of oral mucositis (OM) has been, in part, attributed to differences in host genomics. The aim better define the role of genomics as an OM risk by investigating the association between genetic variants and the presence and severity of OM in pediatric patients with osteosarcoma (OS) undergoing chemotherapy (CT).

Methods: A longitudinal observational retrospective study was conducted.

Anticipating Leucovorin Rescue Therapy in Patients with Osteosarcoma through Methotrexate Population Pharmacokinetic Model.

Methotrexate (MTX), which presents high inter-individual variability, is part of the Brazilian Osteosarcoma Treatment Group (BOTG) protocol. This work aimed to develop a MTX population pharmacokinetic model (POPPK) for Brazilian children with osteosarcoma (OS) following the BOTG protocol to guide rescue therapy and avoid toxicity. The model was developed in NONMEM 7.

Population Pharmacokinetic Model of Methotrexate in Brazilian Pediatric Patients with Acute Lymphoblastic Leukemia.

Objectives: Methotrexate (MTX) is subject to therapeutic drug monitoring because of its high pharmacokinetic variability and safety risk outside the therapeutic window. This study aimed to develop a population pharmacokinetic model (popPK) of MTX for Brazilian pediatric acute lymphoblastic leukemia (ALL) patients who attended the Hospital de Clínicas de Porto Alegre, Brazil.

Methods: The model was developed using NONMEM 7.

Illness perceptions in childhood cancer survivor and caregivers' dyads.

Unlabelled: Surviving childhood cancer is a difficult experience for children and their caregivers, it can produce long-term emotional distress. Illness perceptions refer to the way people understand the different aspects related to illness from their individual and collective experiences.

Objective: to compare the illness perceptions of adolescent childhood cancer survivors and their caregivers and examine the relationship between illness perception of childhood cancer survivors, their caregivers, and sociodemographic, illness, and treatment variables.

Investigation of oral and general health status and IL-1β gene polymorphism as risk factors for oral mucositis in hematopoietic stem cell transplantation patients.

The aim of the present study was to analyze the relationship of OM with possible risk factors such as oral health condition, immunological status and IL-1β profile in patients submitted to hematopoietic stem cell transplantation (HSCT). Fifty-four individuals submitted to HSCT were included. All patients received previous dental treatment and photobiomodulation (PBM) as the institutional OM preventive protocol.

Incidence and risk factors for oral mucositis in pediatric patients receiving chemotherapy.

Purpose: To investigate the incidence and risk factors for oral mucositis (OM) in patients with childhood cancer undergoing chemotherapy.

Methods: Eight hundred and twenty-nine cycles of chemotherapy were evaluated in 112 patients with childhood cancer undergoing chemotherapy. Chemotherapy protocol, hematological, hepatic, and renal function parameters were collected and compared to presence and severity of OM, as graded by the World Health Organization (WHO) scale.

Risk factors associated with the development of oral mucositis in pediatric oncology patients: Systematic review and meta-analysis.

Objectives: Oral mucositis (OM) is an acute toxicity related to cancer treatment. This systematic review aimed to identify potential risk factors associated with the development of OM in pediatric cancer patients.

Methods: A search was performed in four electronic databases to identify studies that analyzed risk factors for OM in pediatric cancer patients.

The effect of hospital care volume on overall survival of children with cancer in Southern Brazil.

Purpose: The purpose of this study was to analyze the effect of hospital care volume on the overall survival of children with cancer in Southern Brazil.

Patients And Methods: We performed a retrospective cohort study of 1378 cancer patients aged 0-19 years, diagnosed with cancer between August 1, 2009 and December 31, 2015 in Rio Grande do Sul, who received hospital treatment in institutions affiliated with the Universal Health Care System (Sistema Único de Saúde [SUS]).

Results: Most children and adolescents were male (56.

Expression of neurotrophins and their receptors in primary osteosarcoma.

Objective: to determine the expression of neurotrophins and their tyrosine-kinase receptors in patients with osteosarcoma (OS) and their correlation with clinical outcomes.

Methods: we applied immunohistochemistry to biopsy specimens of patients consecutively treated for primary OS at a single institution between 2002 and 2015, analyzing them for expression receptors of tyrosine kinase A and B (TrKA and TrKB), neural growth factor (NGF) and brain derived neurotrophic factor (BDNF). Independently, two pathologists classified the immunohistochemical markers as negative (negative or weak focal) or positive (moderate focal/diffuse or strong focal/diffuse).

Gene expression changes associated with chemotherapy resistance in Ewing sarcoma cells.

Ewing Sarcoma (ES) is a highly aggressive bone and soft tissue childhood cancer. The development of resistance to chemotherapy is common and remains the main cause of treatment failure. We herein evaluated the expression of genes associated with chemotherapy resistance in ES cell lines.

Microbiological profile and nutritional quality of a regular diet compared to a neutropenic diet in a pediatric oncology unit.

It has been hypothesized that a neutropenic diet has lower microbe content. Here, the microbiological and nutritional contents of regular and neutropenic diets offered to pediatric patients were analyzed. Microbiological contamination was detected in five of 36 of the food samples analyzed, yet there was no statistical differences between the diets (P = 1.

New photobiomodulation protocol prevents oral mucositis in hematopoietic stem cell transplantation recipients-a retrospective study.

Oral mucositis (OM) is an adverse side effect among hematopoietic stem cell transplantation (HSCT) recipients. The objective of this retrospective study was to evaluate the preventive effect of photobiomodulation (PBM) applied three times per week versus seven times per week in patients undergoing HSCT. The risk factors related to the incidence and severity of OM were also assessed.

What is the impact of local control in Ewing sarcoma: analysis of the first Brazilian collaborative study group - EWING1.

Background: Relapse in localized Ewing sarcoma patients has been a matter of concern regarding poor prognosis. Therefore, we investigated the impact of local control modality (surgery, surgery plus radiotherapy, and radiotherapy) on clinical outcomes such as survival and recurrence in patients with non-metastatic Ewing sarcoma treated on the first Brazilian Collaborative Group Trial of the Ewing Family of Tumors (EWING1).

Methods: Seventy-three patients with localized Ewing sarcoma of bone aged < 30 years were included.

Neurological outcomes after hematopoietic stem cell transplantation for cerebral X-linked adrenoleukodystrophy, late onset metachromatic leukodystrophy and Hurler syndrome.

Objective: To describe survival and neurological outcomes after HSCT for these disorders.

Methods: Seven CALD, 2 MLD and 2 MPS-IH patients underwent HSCT between 2007 and 2014. Neurological examinations, magnetic resonance imaging, molecular and biochemical studies were obtained at baseline and repeated when appropriated.

Combined Treatments with a Retinoid Receptor Agonist and Epigenetic Modulators in Human Neuroblastoma Cells.

Neuroblastoma (NB) is the most common extracranial solid childhood tumor accounting for around 15% of pediatric cancer deaths and most probably originates from a failure in the development of embryonic neural crest cells. Retinoids can inhibit the proliferation and stimulate differentiation of NB cells. In addition, epigenetic events involving changes in chromatin structure and DNA methylation can mediate the effects of retinoids; hence, the scope of this study is to investigate the use of retinoids and epigenetic drugs in NB cell lines.

Low brain-derived neurotrophic factor levels are associated with active disease and poor prognosis in childhood acute leukemia.

Background: Brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related receptor kinase B (TrkB) are involved in the maturation of B lymphocytes in the bone marrow (BM), promote cell differentiation in B-cell malignancies, and are associated with poor prognosis in adults with acute leukemia (AL). However, the role of BDNF in pediatric AL remains poorly understood.

Objective: We carried out a cohort observational study to evaluate BDNF levels in BM or peripheral blood (PB) samples from children with AL.

Trk inhibition reduces cell proliferation and potentiates the effects of chemotherapeutic agents in Ewing sarcoma.

Ewing sarcoma (ES) is a highly aggressive pediatric cancer that may arise from neuronal precursors. Neurotrophins stimulate neuronal devlopment and plasticity. Here, we found that neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), as well as their receptors (TrkA and TrkB, respectively) are expressed in ES tumors.

BDNF/TrkB Signaling as a Potential Novel Target in Pediatric Brain Tumors: Anticancer Activity of Selective TrkB Inhibition in Medulloblastoma Cells.

Medulloblastoma (MB) is the most common malignant pediatric brain tumor. Deregulation of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) signaling has been associated with increased proliferative capabilities, invasiveness, and chemoresistance in several types of cancer. However, the relevance of this pathway in MB remains unknown.

Viability of D283 medulloblastoma cells treated with a histone deacetylase inhibitor combined with bombesin receptor antagonists.

Purpose: Medulloblastoma (MB) comprises four distinct molecular subgroups, and survival remains particularly poor in patients with Group 3 tumors. Mutations and copy number variations result in altered epigenetic regulation of gene expression in Group 3 MB. Histone deacetylase inhibitors (HDACi) reduce proliferation, promote cell death and neuronal differentiation, and increase sensitivity to radiation and chemotherapy in experimental MB.

Carboplatin in the treatment of Ewing sarcoma: Results of the first Brazilian collaborative study group for Ewing sarcoma family tumors-EWING1.

Background: Large cooperative group studies have shown the efficacy of risk-adapted treatment for Ewing sarcoma. However, validation and local adaptation by National cooperative groups is needed. A multicenter protocol to determine the efficacy and safety of a risk-adapted intensive regimen was developed by the Brazilian cooperative group.

The use of high-frequency audiometry increases the diagnosis of asymptomatic hearing loss in pediatric patients treated with cisplatin-based chemotherapy.

Background: Cisplatin may cause permanent cochlear damage by changing cochlear frequency selectivity and can lead to irreversible sensorineural hearing loss. High-frequency audiometry (HFA) is able to assess hearing frequencies above 8,000 Hz; hence, it has been considered a high-quality method to monitor and diagnose early and asymptomatic signs of ototoxicity in patients receiving cisplatin.

Procedure: Forty-two pediatric patients were evaluated for hearing loss induced by cisplatin utilizing HFA, and its diagnostic efficacy was compared to that of standard pure-tone audiometry and distortion-product otoacoustic emissions (DPOAEs).