International Society of Paediatric Oncology (SIOP) Global Mapping Programme: Latin American Society of Pediatric Oncology (SLAOP) country-level report.

BACKGROUND: Latin American countries are improving childhood cancer care, showing strong commitment to implement the Global Initiative for Childhood Cancer, but there are scant publications of the situation at a continental level. METHODS: As part of the International Society of Paediatric Oncology Global Mapping project, delegates of each country participating in the Latin American Society of Pediatric Oncology (SLAOP) and chairs of national pediatric oncology societies and cooperative groups were invited to provide information regarding availability of national pediatric cancer control programs (NPCCP), pediatric oncology laws, pediatric oncology tumor registries, and training programs and support to diagnosis and treatment. RESULTS: Nineteen of the 20 countries participating in SLAOP responded. National delegates reported nine countries with NPCCP and four of them were launched in the past 5 years. National pediatric tumor registries are available in eight countries, and three provided published survival results. Fellowship programs for training pediatric oncologists are available in 12 countries. National delegates reported that eight countries provide support to most essential diagnosis and treatments and 11 provide partial or minimal support that is supplemented by civil society organizations. Seven countries have a pediatric oncology law. There are three international cooperative groups and four national societies for pediatric oncology. CONCLUSION: Despite many challenges, there were dramatic advances in survivorship, access to treatment, and availability of NPCCP in Latin America. Countries with highest social development scores in general provide more complete support and are more likely to have NPCCP, training programs, and reported survival results.

Access to Methotrexate Monitoring in Latin America: A Multicountry Survey of Supportive Care Capacity.

High-dose methotrexate (HDMTX) is used to treat a broad spectrum of cancers. Methotrexate (MTX) monitoring and adequate supportive care are critical for safe drug administration; however, MTX level timing is not always possible in low- and middle-income countries. The aim of this study was to evaluate HDMTX supportive care capacity and MTX monitoring practices in Latin America (LATAM) to identify gaps and opportunities for improvement. A multicenter survey was conducted among LATAM pediatric oncologists. Twenty healthcare providers from 20 institutions answered the online questionnaire. HDMTX was used to treat acute lymphoblastic leukemia (ALL; 100%), non-Hodgkin lymphoma (84.2%), diffuse large B-cell lymphoma (47.4%), osteosarcoma (78.9%), and medulloblastoma (31.6%). Delays in starting HDMTX infusion were related to bed shortages (47.4%) and MTX shortages (21.1%). MTX monitoring was performed at an in-hospital laboratory in 52%, at an external/nearby laboratory in 31.6%, and was not available in 10.5%. Median interval between sampling and obtaining MTX levels was ≤ 2 h in 45% and ≥ 6 h in 30%, related to laboratory location. Sites without access to MTX monitoring reduced the MTX dose for patients with high-risk ALL or did not include MTX in the treatment of patients with osteosarcoma. Respondents reported that implementation of point-of-care testing of MTX levels is feasible. In LATAM, highly variable supportive care capacity may affect the safe administration of MTX doses. Improving accessibility of MTX monitoring and the speed of obtaining results should be prioritized to allow delivery of full doses of MTX required by the current protocols.

Impact of COVID-19 in pediatric oncology care in Latin America during the first year of the pandemic.

BACKGROUND: The ongoing coronavirus 2019 disease (COVID-19) pandemic strained medical systems worldwide. We report on the impact on pediatric oncology care in Latin American (LATAM) during its first year. METHOD: Four cross-sectional surveys were electronically distributed among pediatric onco-hematologists in April/June/October 2020, and April/2021 through the Latin American Society of Pediatric Oncology (SLAOP) email list and St Jude Global regional partners. RESULTS: Four hundred fifty-three pediatric onco-hematologists from 20 countries responded to the first survey, with subsequent surveys response rates above 85%. More than 95% of participants reported that treatment continued without interruption for new and active ongoing patients, though with disruptions in treatment availability. During the first three surveys, respondents reported suspensions of outpatient procedures (54.2%), a decrease in oncologic surgeries (43.6%), radiotherapy (28.4%), stem cell transplants (SCT) (69.3%), and surveillance consultations (81.2%). Logistic regression analysis showed that at the beginning of the first wave, participants from countries with healthcare expenditure below 7% were more likely to report a decrease in outpatient procedures (odds ratio [OR]: 1.84, 95% CI: 1.19-2.8), surgeries (OR: 3, 95% CI: 1.9-4.6) and radiotherapy (OR: 6, 95% CI: 3.5-10.4). Suspension of surveillance consultations was higher in countries with COVID-19 case fatality rates above 2% (OR: 3, 95% CI: 1.4-6.2) and SCT suspensions in countries with COVID-19 incidence rate above 100 cases per 100,000 (OR: 3.48, 95% CI: 1.6-7.45). Paradoxically, at the beginning of the second wave with COVID-19 cases rising exponentially, most participants reported improvements in cancer services availability. CONCLUSION: Our data show the medium-term collateral effects of the pandemic on pediatric oncology care in LATAM, which might help delineate oncology care delivery amid current and future challenges posed by the pandemic.

Cytokine and chemokine profiles in episodes of persistent high-risk febrile neutropenia in children with cancer.

BACKGROUND: In children with cancer and persistent high-risk febrile neutropenia (HRFN), cytokines/chemokines profiles can guide the differentiation of febrile neutropenia (FN) due to infections and episodes of unknown origin (FN-UO). METHODS: A prospective, multicenter study in Santiago, Chile included patients ≤ 18 years with cancer and HRFN. Clinical and microbiological studies were performed according to validated protocols. Serum levels of 38 cytokines/chemokines were determined on day 4 of persistent HRFN. We performed comparisons between i) HRFN episodes with a detected etiological agent (FN-DEA) and FN-UO, and ii) bacterial versus viral infections. ROC curves were used to assess the discriminatory power of the analytes. RESULTS: 110 HRFN episodes were enrolled (median age 8 years, 53% female). Eighty-four patients were FN-DEA: 44 bacterial, 32 viral, and 8 fungal infections. Twenty-six cases were categorized as FN-UO. Both groups presented similar clinical and laboratory characteristics. Nineteen out of 38 analytes had higher concentrations in the FN-DEA versus FN-UO group. G-CSF, IL-6, and Flt-3L showed the highest discriminatory power to detect infection (AUC 0.763, 0.741, 0.701). Serum levels of G-CSF differentiated bacterial infections and IP-10 viral agents. A combination of G-CSF, IL-6, Flt-3L, and IP-10 showed an AUC of 0.839, 75% sensitivity, and 81% specificity. CONCLUSION: A specific immune response is present on day four of persistent HRFN in children with cancer. We propose a combined measure of serum concentrations of G-CSF, IL-6, IP-10, and Flt-3L, in order to predict the presence of an infectious agent as compared to an episode of FN with unknown origin.

Usefulness of serum galactomannan in initiating and modifying antifungal therapy in children with cancer and persistent high-risk febrile neutropenia.

BACKGROUND: Invasive fungal disease is a major cause of morbidity and mortality in children with cancer and high-risk febrile neutropenia (HRFN). Repeated serum galactomannan (sGM) measurements have been described as an effective tool to guide therapy in adults under suspicion of invasive aspergillosis. However, the utility of this approach has not been reported in paediatric population. OBJECTIVES: To evaluate the usefulness of sGM measurements in initiating and modifying antifungal therapy (AFT) in children with cancer and persistent HRFN. PATIENTS/METHODS: Nested case-control study in children with cancer and persistent HRFN episodes, between July 2013 and January 2019. Patients were classified as cases and controls depending on if they received AFT or not, respectively. Through odds ratio analysis, we assessed the role of sGM positivity in the AFT initiation decision. Then, we analysed the group of patients that initiated AFT, and compared those who had AFT modifications and those who did not, analysing different sGM kinetics thresholds. RESULTS: A total of 191 episodes from children with persistent HRFN were enrolled, of which 107 received AFT and 84 did not. The median age was 7 years (IQR 4-12), 52% were male and 89% had a haematologic malignancy as underlying disease. Positive sGM was not associated with AFT initiation (OR 0.99, 95% CI 0.43-2.33, P = .99). A difference threshold in sGM Δ ≥ 0.3 sGM was significantly associated with AFT modification (OR 5.07, 95% CI 1.02- 25.70, P = .04). CONCLUSIONS: Our results suggest the utility of serial sGM sampling during AFT in children with persistent HRFN.

Impact of a structured educational programme for caregivers of children with cancer on parental knowledge of the disease and paediatric clinical outcomes during the first year of treatment.

OBJECTIVE: To assess the impact of a structured educational programme for caregivers of children with cancer on their level of knowledge about the disease and patient's clinical outcome. METHODS: This prospective, non-randomised, experimental study included caregivers of recently diagnosed children at two hospitals in Chile. Caregivers whose children were treated at the first centre were the structured education programme group (EPG), while the second hospital provided the standard care (SCG). We evaluated caregivers' level of knowledge on days 1, 10 and 90 as well as the children's clinical outcomes over 1 year of treatment. RESULTS: A total of 102 caregivers were enrolled between 2014 and 2015. Only the EPG showed a significant increase in knowledge between days 1 and 90. The rate of central venous catheter infections was significantly lower in the EPG versus SCG (7% versus 26%; p = .01). The risk ratio was 0.35 (95% CI = 0.13-0.94), and a log-rank test showed a statistically significant difference between the two groups (p = .018). There were also fewer Emergency Department visits in the EPG for fever episodes. CONCLUSION: Providing a structured education to caregivers increased their level of knowledge and improved the clinical outcome of their children during the first year of treatment.

The cancer-related transcription factor RUNX2 modulates expression and secretion of the matricellular protein osteopontin in osteosarcoma cells to promote adhesion to endothelial pulmonary cells and lung metastasis.

Osteosarcomas are bone tumors that frequently metastasize to the lung. Aberrant expression of the transcription factor, runt-related transcription factor 2 (RUNX2), is a key pathological feature in osteosarcoma and associated with loss of p53 and miR-34 expression. Elevated RUNX2 may transcriptionally activate genes mediating tumor progression and metastasis, including the RUNX2 target gene osteopontin (OPN/SPP1). This gene encodes a secreted matricellular protein produced by osteoblasts to regulate bone matrix remodeling and tissue calcification. Here we investigated whether and how the RUNX2/OPN axis regulates lung metastasis of osteosarcoma. Importantly, RUNX2 depletion attenuates lung metastasis of osteosarcoma cells in vivo. Using next-generation RNA-sequencing, protein-based assays, as well as the loss- and gain-of-function approaches in selected osteosarcoma cell lines, we show that osteopontin messenger RNA levels closely correlate with RUNX2 expression and that RUNX2 controls the levels of secreted osteopontin. Elevated osteopontin levels promote heterotypic cell-cell adhesion of osteosarcoma cells to human pulmonary microvascular endothelial cells, but not in the presence of neutralizing antibodies. Collectively, these findings indicate that the RUNX2/OPN axis regulates the ability of osteosarcoma cells to attach to pulmonary endothelial cells as a key step in metastasis of osteosarcoma cells to the lung.

Efficacy of pre-emptive versus empirical antifungal therapy in children with cancer and high-risk febrile neutropenia: a randomized clinical trial.

Objectives: To compare the efficacy of pre-emptive versus empirical antifungal therapy in children with cancer, fever and neutropenia. Methods: This was a prospective, multicentre, randomized clinical trial. Children presenting with persistent high-risk febrile neutropenia at five hospitals in Santiago, Chile, were randomized to empirical or pre-emptive antifungal therapy. The pre-emptive group received antifungal therapy only if the persistent high-risk febrile neutropenia was accompanied by clinical, laboratory, imaging or microbiological pre-defined criteria. The primary endpoint was overall mortality at day 30 of follow-up. Secondary endpoints included invasive fungal disease (IFD)-related mortality, number of days of fever, days of hospitalization and use of antifungal drugs, percentage of children developing IFD, requiring modification of initial treatment strategy and need for ICU. The trial was registered with Registro Brasileiro de Ensaios Clínicos (ReBEC) under trial number RBR-3m9d74. Results: A total of 149 children were randomized, 73 to empirical therapy and 76 to pre-emptive therapy. Thirty-two out of 76 (42%) children in the pre-emptive group received antifungal therapy. The median duration of antifungal therapy was 11 days in the empirical arm and 6 days in the pre-emptive arm (P < 0.001), with similar overall mortality (8% in the empirical arm and 5% in the pre-emptive arm, P = 0.47). IFD-related mortality was the same in both groups (3%, P = 0.97), as were the percentage of children with IFD (12%, P = 0.92) and the number of days of fever (9, P = 0.76). The number of days of hospitalization was 19 in the empirical arm and 17 in the pre-emptive arm (P = 0.15) and the need for ICU was 25% in the empirical arm and 20% in the pre-emptive arm (P = 0.47). Conclusions: Pre-emptive antifungal therapy was as effective as empirical antifungal therapy in children with cancer, fever and neutropenia, significantly reducing the use of antifungal drugs.

[Successful treatment of a persistent rhino-cerebral mucormycosis in a pediatric patient with a debut of acute lymphoblastic leukemia]. / Tratamiento exitoso de una mucormicosis rinocerebral persistente en un paciente pediátrico durante el debut de una leucemia aguda.

The fungi of the order Mucorales cause mucormycosis, which usually presents as an invasive fungal disease with rapid angioinvasion in immunocompromised patients. Rhinocerebral is the most common presentation. The lipid formulations of amphotericin B are used as primary treatment in invasive mucormycosis; the combined use of posaconazole could allow a reduction in the dose of amphotericin B improving tolerance and adherence to treatment. Caspofungin and amphotericin B association has been shown to be synergistic in vitro and effective in murine models. We present the case of a preschool patient that during the debut of acute lymphoblastic leukemia developed a rhinocerebral mucormycosis successfully responding to antifungal treatment with the combination of liposomal amphotericin and caspofungin.

[Seroconversion in response to a reinforced primary hepatitis B vaccination in children with cancer]. / Seroconversión frente a primovacunación reforzada contra hepatitis B en niños con cáncer.

INTRODUCTION: Immune response against vaccine antigens may be impaired in children with cancer. The aim of this study was to evaluate the seroconversion response against hepatitis B vaccination (HBV) at the time of chemotherapy onset and/or remission in children with cancer. PATIENTS AND METHOD: Prospective, two-centre, controlled, non-randomised study conducted on children recently diagnosed with cancer, paired with healthy subjects. Cases received HBV at time 0, 1 and 6 months with DNA recombinant HBV at a dose of 20 and 40 µg if < or > than 10 years of age, respectively, at the time of diagnosis for solids tumours and after the remission in case of haematological tumours. Controls received the same schedule, but at of 10 and 20 µg doses, respectively. HBs antibodies were measured in serum samples obtained at 2, 8 and 12 months post-vaccination. Protective titres were defined as > 10 mIU/ml at 8th month of follow up. RESULTS: A total of 78 children with cancer and 25 healthy controls were analysed at month 8th of follow up. Seroconversion rates in the cancer group reached 26.9%, with no differences by age, gender or type of tumour (P = .13, .29, and .44, respectively). Control group seroconversion was 100% at the 8th month, with P < .0001 compared with the cancer group. At month 12 of follow up, just 31.9% of children with cancer achieved anti-HBs antibodies > 10 mIU/ml. CONCLUSIONS: Vaccination against hepatitis B with three doses of DNA recombinant vaccine at an increased concentration, administrated at the time of onset of chemotherapy and/or remission provided an insufficient immune response in a majority of children with cancer. More immunogenic vaccines should be evaluated in this special population, such as a third generation, with more immunogenic adjuvants, enhanced schedules at 0, 1, 2, 6 month, evaluation of antibody titres at month 8 and 12h to evaluate the need for further booster doses.

Prevalence of TPMT and ITPA gene polymorphisms and effect on mercaptopurine dosage in Chilean children with acute lymphoblastic leukemia.

BACKGROUND: Mercaptopurine (6-MP) plays a pivotal role in treatment of childhood acute lymphoblastic leukemia (ALL); however, interindividual variability in toxicity of this drug due to genetic polymorphism in 6-MP metabolizing enzymes has been described. We determined the prevalence of the major genetic polymorphisms in 6-MP metabolizing enzymes in Chilean children with ALL. METHODS: 103 Chilean pediatric patients with a confirmed diagnosis of ALL were enrolled. DNA was isolated from whole blood and genetic polymorphism in thiopurine S-methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) coding genes were detected by polymorphism chain reaction-restriction fragment length (PCR-RFLP) assay. RESULTS: The total frequency of variant TPMT alleles was 8%. TPMT*2, TPMT*3A and TPMT*3B alleles were found in 0%, 7%, and 1% of patients, respectively. For ITPA, the frequency of P32T allele was 3%. We did not observe any homozygous variant for TPMT and ITPA alleles. We also analyzed a subgroup of 40 patients who completed the maintenance phase of ALL treatment, and we found that patients carrying a TPMT gene variant allele required a significantly lower median cumulative dosage and median daily dosage of 6-MP than patients carrying wild type alleles. CONCLUSION: TMPT genotyping appears an important tool to further optimize 6-MP treatment design in Chilean patients with ALL.

[Characterization of episodes of febrile neutropenia in children with acute myeloid leukemia and acute lymphoblastic leukemia]. / Caracterización de los episodios de neutropenia febril en niños con leucemia mieloide aguda y leucemia linfoblástica aguda.

INTRODUCTION: Leukemia is the most common cancer in Chilean children. Acute lymphoblastic leukemia (ALL) is more prevalent and longer survival compared to acute myeloid leukemia (AML). AIMS: To describe episodes of febrile neutropenia (FN) in children with AML, determining frequency of infections as agent, focus and evolution, comparing children with ALL episodes. METHOD: A prospective multicenter study. Children presenting with FN at six hospitals in Santiago, Chile, were invited to participate in two consecutive FONDECYT projects, from April 2004 to June 2011. All patients were uniformly evaluated, recording epidemiological, clinical and laboratory variables. Information regarding FN episodes of children with LMA and LLA was used to this study. RESULTS: We evaluated 506 episodes of FN in children with leukemia: 173 children with AML and 333 in children with ALL. NF episodes in children with ALML showed significantly greater depth and duration of neutropenia, febrile remained a > period of time and had a worse clinical outcome, as evidenced by > hemodynamic instability, > sepsis, CRP > 90 mg/L for a longer time, more days of hospitalization, > frequency of hospitalization in ICU, > bacteremia, mainly by Streptococcus viridans group, > change of antimicrobial treatment, > use of antifungal therapy. CONCLUSIONS: This study demonstrates that FN episodes in children with ALML further evolve unfavorably, compared with episodes of FN in children with ALL. FN episodes in children with ALML require a more aggressive diagnostic and therapeutic approach, related to its severity.

Efficacy and safety of withholding antimicrobial therapy in children with cancer, fever, and neutropenia, with a demonstrated viral respiratory infection: a randomized clinical trial.

OBJECTIVES: To validate the efficacy and safety of withholding antimicrobial therapy in a new cohort of children with cancer and febrile neutropenia (FN) having a demonstrated viral respiratory tract infection. METHODS: Prospective, multicenter, noninferiority, randomized study, approved by the ethical committee, in children presenting with FN at seven hospitals in Chile, evaluated at admission for diagnosis of bacterial and viral pathogens. Children who were positive for a respiratory virus, negative for a bacterial pathogen, and had a favourable evolution after 48-72 hours of antimicrobial therapy were randomized to either maintain or withhold antimicrobial therapy. The primary endpoint was the percentage of episodes with an uneventful resolution, whereas the secondary endpoints were days of fever, days of hospitalization, requirement of antimicrobial treatment readministration, sepsis, paediatric intensive care unit admission, and death. RESULTS: A total of 301 of 939 children with FN episodes recruited between March 2021 and December 2023 had a respiratory virus as a unique identified microorganism, of which 139 had a favourable evolution at 48-72 hours and were randomized, 70 to maintain and 69 to withdraw antimicrobial therapy. The median days of antimicrobial therapy was 5 (IQR 3-6) versus 3 (IQR 3-6) days (p < 0.001), with similar frequency of uneventful resolution 66/70 (94%) and 66/69 (96%); relative risk, 1.01; (95% CI, 0.93 to 1.09), absolute risk difference 0.01; (95% CI, -0.05 to 0.08) and similar number of days of fever and days of hospitalization. No cases of sepsis, paediatric intensive care unit admission, or death were reported. DISCUSSION: We validated the strategy of withdrawal antimicrobial therapy in children with FN and viral respiratory tract infection based on clinical and microbiological/molecular diagnostic criteria. This will enable advances in antimicrobial stewardship strategies with a possible future impact on antimicrobial resistance.

Dynamic contrast-enhanced magnetic resonance imaging as a prognostic factor in predicting event-free and overall survival in pediatric patients with osteosarcoma.

BACKGROUND: The objective of this study was to prospectively evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as an early imaging indicator of tumor histologic response to preoperative chemotherapy and as a possible prognostic factor for event-free survival (EFS) and overall survival in pediatric patients with newly diagnosed, nonmetastatic osteosarcoma who were treated on a single, multi-institutional phase 2 trial. METHODS: Three serial DCE-MRI examinations at week 0 (before treatment), week 9, and week 12 (tumor resection) were performed in 69 patients with nonmetastatic osteosarcoma to monitor the response to preoperative chemotherapy. Four DCE-MRI kinetic parameters (the influx volume transfer constant [K(trans) ], the efflux rate constant [k(ep) ], the relative extravascular extracellular space [v(e) ], and the relative vascular plasma space [v(p) ]) and the corresponding differences (ΔK(trans) , Δk(ep) , Δv(e) , and Δv(p) ) of averaged kinetic parameters between the outer and inner halves of tumors were calculated to assess their associations with tumor histologic response, EFS, and overall survival. RESULTS: The parameters K(trans) , v(e) , v(p) , and k(ep) decreased significantly from week 0 to week 9 and week 12. The parameters K(trans) , v(p) , and Δk(ep) at week 9 were significantly different between responders and nonresponders (P = .046, P = .021, and P = .008, respectively). These 3 parameters were indicative of histologic response. The parameter Δv(e) at week 0 was a significant prognostic factor for both EFS (P = .02) and overall survival (P = .03). CONCLUSIONS: DCE-MRI was identified as a prognostic factor for EFS and overall survival before treatment on this trial and was indicative of a histologic response to neoadjuvant therapy. Further studies are needed to verify these findings with other treatment regimens and establish the potential role of DCE-MRI in the development of risk-adapted therapy for osteosarcoma.

[Seroprevalence of varicella-zoster virus in children with cancer in six hospitals in Santiago, Chile]. / Seroprevalencia de virus varicela-zoster en niños con cáncer en seis hospitales de Santiago, Chile.

UNLABELLED: Infections with varicella-zoster virus (VVZ) in immunocompromised children imply a high mortality. There is no data about VVZ seroprevalence in children with cancer in our country. AIM: To determine the prevalence of VVZ antibodies in children with cancer who have undergone chemotherapy or have undergone a hematopoietic stem cell transplant. METHODOLOGY: collaborative, multicenter study. Serum samples were collected from 281 children with cancer and episodes of febrile neutropenia from 6 hospitals belonging to the public health network in the Metropolitan Region between June 2004 and August 2006. These samples were stored at -70 ° C, and 200 of them were randomly chosen and analyzed to determine VVZ IgG (ELISA). RESULTS: 179 samples from 179 children, 65% male. Ninety eighth/179 (55%) were positive, 72/179 (40%) negative and 9/179 (5%) indeterminate. Stratified by age, seropositive percentage was: 1 to 4 years 32%, 5-9 years 42%, 10-14 years 78%, over 15 years 88%. CONCLUSION: Forty percent of children treated for cancer are seronegative to VVZ infection, a frequency that decreases with age. These results support the adoption of preventive measures to avoid infection in this population of children at risk of developing a serious and possibly fatal illness.

[Bloodstream infections in children with cancer and high risk fever and neutropenia episodes in six hospitals of Santiago, Chile between 2004 and 2009]. / Agentes causantes de bacteriemia en niños con cáncer y neutropenia febril de alto riesgo en seis hospitales de Santiago, Chile, período 2004-2009.

INTRODUCTION: To determine the etiology of invasive bacterial infection in high risk febrile neutropenia (HRFN) episodes in children with cancer is essential because of the favorable impact on mortality of the early empiric antibiotic treatment. OBJECTIVE: To determine the etiology of bacteremia in pediatric patients with cancer and HRFN in the National Child Program of Antineoplastic Drugs during the 2004-2009 period, and compare these agents and their antimicrobial susceptibility with the period 1994-1998 described in a previous study. METHODS: The causative agents of bacteremia were prospectively recorded in patients less than 18 years of age receiving chemotherapy for cancer with HRFN and positive blood cultures admitted to one of the six hospitals from the Child Program of Antineoplastic Drugs network during the period 2004-2009. RESULTS: 839 episodes of HRFN were identified; 181 blood cultures were positive in the following proportion: gram positive cocci (56%), gram negative bacilli (42%) and yeast (2%).The most common etiologic agents were Staphylococcus coagulase negative (25%), Escherichia. coli (20%), group viridans Streptococcus (14%), Staphylococcus aureus (13%) and Pseudomonas aeruginosa (9%). Comparing the two periods, the relative frequency of Streptococcus spp increased from 4 to 17%, coagulase negative Staphylococcus decreased from 44 to 25%, showing an increase in their resistance to oxacillin from 55% to 77%. CONCLUSIONS: We describe the main etiological agents from HRFN episodes in children with cancer in a 5 years period. This information could help for a better approach in the empirical antimicrobial therapy in this population.

Mapping Pediatric Oncology Clinical Trial Collaborative Groups on the Global Stage.

PURPOSE: The global pediatric oncology clinical research landscape, particularly in Central and South America, Africa, and Asia, which bear the highest burden of global childhood cancer cases, is less characterized in the literature. Review of how existing pediatric cancer clinical trial groups internationally have been formed and how their research goals have been pursued is critical for building global collaborative research and data-sharing efforts, in line with the WHO Global Initiative for Childhood Cancer. METHODS: A narrative literature review of collaborative groups performing pediatric cancer clinical research in each continent was conducted. An inventory of research groups was assembled and reviewed by current pediatric cancer regional and continental leaders. Each group was narratively described with identification of common structural and research themes among consortia. RESULTS: There is wide variability in the structure, history, and goals of pediatric cancer clinical trial collaborative groups internationally. Several continental regions have longstanding endogenously-formed clinical trial groups that have developed and published numerous adapted treatment regimens to improve outcomes, whereas other regions have consortia focused on developing foundational database registry infrastructure supported by large multinational organizations or twinning relationships. CONCLUSION: There cannot be a one-size-fits-all approach to increasing collaboration between international pediatric cancer clinical trial groups, as this requires a nuanced understanding of local stakeholders and resources necessary to form partnerships. Needs assessments, performed either by local consortia or in conjunction with international partners, have generated productive clinical trial infrastructure. To achieve the goals of the Global Initiative for Childhood Cancer, global partnerships must be sufficiently granular to account for the distinct needs of each collaborating group and should incorporate grassroots approaches, robust twinning relationships, and implementation science.

Frontline treatment of localized osteosarcoma without methotrexate: results of the St. Jude Children's Research Hospital OS99 trial.

BACKGROUND: The standard treatment of osteosarcoma includes cisplatin and high-dose methotrexate (HDMTX); both agents exert significant toxicity, and HDMTX requires complex pharmacokinetic monitoring and leucovorin rescue. In the previous OS91 trial, the treatment of localized disease with carboplatin, ifosfamide, doxorubicin, and HDMTX yielded outcomes comparable to those of cisplatin-based regimens and caused less toxicity. To build on this experience, the authors conducted a multi-institutional trial (OS99) that evaluated the efficacy of carboplatin, ifosfamide, and doxorubicin without HDMTX in patients with newly diagnosed, localized, resectable osteosarcoma. METHODS: Treatment was comprised of 12 cycles of chemotherapy administered over 35 weeks: 3 cycles of carboplatin (dose targeted to area under the concentration-time curve of 8 mg/mL × min on Day 1) and ifosfamide (at a dose of 2.65 g/m(2) daily ×3 days) and 1 cycle of doxorubicin (at a dose of 25 mg/m(2) daily ×3 days) before surgical resection, followed by 2 additional cycles of the combination of carboplatin and ifosfamide and 3 cycles each of doxorubicin (25 mg/m(2) daily ×2 days) combined with ifosfamide or carboplatin. RESULTS: A total of 72 eligible patients (median age, 13.4 years) were enrolled between May 1999 and May 2006. Forty of the 66 (60.6%) evaluable patients had good histologic responses (>90% tumor necrosis) to preoperative chemotherapy. The estimated 5-year event-free survival rate was 66.7% ± 7.0% for the OS99 trial compared with 66.0% ± 6.8% for the OS91 trial (P = .98). The estimated 5-year survival rate was 78.9% ± 6.3% for the OS99 trial and 74.5% ± 6.3% for the OS91 trial (P = .40). CONCLUSIONS: The regimen used in the OS99 trial was found to produce outcomes comparable to those of cisplatin-containing or HDMTX-containing regimens. This therapy offers a good alternative for patients, particularly those who demonstrate an intolerance of HDMTX, and for institutions that cannot provide pharmacokinetic monitoring for MTX.

[Clinical characteristics and microbiological profile of viridans group streptococci bacteremia in children with cancer and high-risk febrile neutropenia]. / Caracterización clínica y microbiológica de episodios de bacteriemia por Streptococcus grupo viridans en niños con cáncer y neutropenia febril de alto riesgo.

BACKGROUND: Viridans group streptococci (VGS) has acquired relevance as a microorganism causing febrile neutropenia, associated with significant morbidity. AIM: To characterize episodes of bacteremia caused by VGS in children with cancer who developed high-risk febrile neutropenia (HRFN) during the period from April 2004 to June 2018 in six pediatric hospitals of Santiago, Chile. METHOD: Database analysis of 4 successive, prospective and multicentric studies recording clinical and laboratory characteristics of patients, as well as antimicrobial susceptibility pattern of isolated strains. RESULTS: 95 episodes of VGS bacteremia in 91 children with HRFN were analyzed. It emphasizes acute myeloid leukemia as cancer type, deep neutropenia, prolonged hospitalization (15 days), with extended use of antimicrobials (14 days) and use of cytarabine in chemotherapy schemes (86% episodes). The most frequent clinical manifestations were respiratory and gastrointestinal, associating up to 26% viridans group shock syndrome. There was high resistance to ß lactams. As expected, there were not non-susceptible strains to vancomycin. DISCUSSION: VGS is a relevant microorganism in children with cancer, fever and neutropenia, with a high percentage of sepsis. Resistance to ß lactams is an issue that requires strict epidemiological surveillance in this population.

Predictors of severe sepsis not clinically apparent during the first twenty-four hours of hospitalization in children with cancer, neutropenia, and fever: a prospective, multicenter trial.

BACKGROUND: Severe sepsis is not clinically apparent during the first 24 hours of hospitalization in most children with cancer and febrile neutropenia (FN), delaying targeted interventions that could impact mortality. The aim of this study was to prospectively evaluate biomarkers obtained within 24 hours of hospitalization as predictors of severe sepsis before it becomes clinically evident. METHODS: Children with cancer, admitted with FN at high risk for an invasive bacterial infection in 6 public hospitals in Santiago, Chile, were monitored throughout their clinical course for occurrence of severe sepsis. Clinical, demographic and 6 biomarkers [eg, blood urea nitrogen, serum glucose, lactic dehydrogenase, serum C-reactive protein (CRP), interleukin (IL)-8, and procalcitonin] were obtained at the time of admission and after 24 hours. Biomarkers independently associated with severe sepsis diagnosed after the first 24 hours of hospitalization were identified by logistic regression analysis. RESULTS: A total of 601 high risk FN episodes were enrolled between June 2004 and October 2006; 151 (25%) developed severe sepsis of which 116 (77%) were not clinically apparent during the first 24 hours of hospitalization. Risk factors for severe sepsis were age > or =12 years [odds ratio (OR): 3.85; 95% confidence interval (CI): 2.41-6.15], admission CRP > or =90 mg/L (OR: 2.03; 95% CI: 1.32-3.14), admission IL-8 > or =200 pg/mL (OR: 2.39; 95% CI: 1.51-3.78), 24-hour CRP > or =100 mg/L (OR: 3.06; 95% CI: 1.94-4.85), and 24-hour IL-8 > or =300 pg/mL (OR: 3.13; 95% CI 1.92-5.08). CONCLUSIONS: Age > or =12 years and admission or 24-hour values of CRP > or =90/100 mg/L and IL-8 > or =200/300 pg/mL are predictors of sepsis not clinically apparent during the first 24 hours of hospitalization.