Treatment-related mortality in children with cancer in low-income and middle-income countries: a systematic review and meta-analysis.

BACKGROUND: Approximately 90% of children with cancer live in low-income and middle-income countries (LMICs), where 5-year survival is lower than 20%. Treatment-related mortality in high-income countries is approximately 3-5%; however, in LMICs, treatment-related mortality has been reported in up to 45% of children with cancer. This study aimed to systematically explore the burden of treatment-related mortality in children with cancer in LMICs and to explore the association between country income level and treatment-related mortality. METHODS: For this systematic review and meta-analysis we identified articles published between Jan 1, 2010, and June 22, 2021, describing treatment-related mortality in paediatric patients (aged 0-21 years) with cancer in LMICs. We searched PubMed, Trip, Web of Science, Embase, and the WHO Global Metric Index databases. The search was limited to full-text articles and excluded case reports (<10 patients) and haematopoietic stem-cell transplantation recipients. Two reviewers independently screened studies for eligibility, extracted data from included publications, and evaluated data quality. Random and mixed-effects models were used to estimate treatment-related mortality burden and trends. The Cochran-Q statistic was used to assess heterogeneity between studies. This study is registered on PROSPERO (CRD42021264849). FINDINGS: Of 13 269 identified abstracts, 501 studies representing 68 351 paediatric patients with cancer were included. The treatment-related mortality estimate was 6·82% (95% CI 5·99-7·64), accounting for 30·9% of overall mortality (4437 of 14 358 deaths). Treatment-related mortality was inversely related to country income. Treatment-related mortality was 14·19% (95% CI 9·65-18·73) in low-income countries, 9·21% (7·93-10·49) in lower-middle-income countries, and 4·47% (3·42-5·53) in upper-middle-income countries (Cochran-Q 42·39, p<0·0001). In upper-middle-income countries, the incidence of treatment-related mortality decreased over time (slope -0·002, p=0·0028); however, outcomes remained unchanged in low-income (p=0·21) and lower-middle-income countries (p=0·16). INTERPRETATION: Approximately one in 15 children receiving cancer treatment in LMICs die from treatment-related complications. Although treatment-related mortality has decreased in upper-middle-income countries over time, it remains unchanged in LMICs. There is an urgent need for targeted supportive care interventions to reduce global disparities in childhood cancer survival. FUNDING: American Lebanese Syrian Associated Charities and National Cancer Institute.

Effect of paediatric early warning systems (PEWS) implementation on clinical deterioration event mortality among children with cancer in resource-limited hospitals in Latin America: a prospective, multicentre cohort study.

BACKGROUND: Paediatric early warning systems (PEWS) aid in the early identification of clinical deterioration events in children admitted to hospital. We aimed to investigate the effect of PEWS implementation on mortality due to clinical deterioration in children with cancer in 32 resource-limited hospitals across Latin America. METHODS: Proyecto Escala de Valoración de Alerta Temprana (Proyecto EVAT) is a quality improvement collaborative to implement PEWS in hospitals providing childhood cancer care. In this prospective, multicentre cohort study, centres joining Proyecto EVAT and completing PEWS implementation between April 1, 2017, and May 31, 2021, prospectively tracked clinical deterioration events and monthly inpatient-days in children admitted to hospital with cancer. De-identified registry data reported between April 17, 2017, and Nov 30, 2021, from all hospitals were included in analyses; children with limitations on escalation of care were excluded. The primary outcome was clinical deterioration event mortality. Incidence rate ratios (IRRs) were used to compare clinical deterioration event mortality before and after PEWS implementation; multivariable analyses assessed the correlation between clinical deterioration event mortality and centre characteristics. FINDINGS: Between April 1, 2017, and May 31, 2021, 32 paediatric oncology centres from 11 countries in Latin America successfully implemented PEWS through Proyecto EVAT; these centres documented 2020 clinical deterioration events in 1651 patients over 556 400 inpatient-days. Overall clinical deterioration event mortality was 32·9% (664 of 2020 events). The median age of patients with clinical deterioration events was 8·5 years (IQR 3·9-13·2), and 1095 (54·2%) of 2020 clinical deterioration events were reported in male patients; data on race or ethnicity were not collected. Data were reported per centre for a median of 12 months (IQR 10-13) before PEWS implementation and 18 months (16-18) after PEWS implementation. The mortality rate due to a clinical deterioration event was 1·33 events per 1000 patient-days before PEWS implementation and 1·09 events per 1000 patient-days after PEWS implementation (IRR 0·82 [95% CI 0·69-0·97]; p=0·021). In the multivariable analysis of centre characteristics, higher clinical deterioration event mortality rates before PEWS implementation (IRR 1·32 [95% CI 1·22-1·43]; p<0·0001), being a teaching hospital (1·18 [1·09-1·27]; p<0·0001), not having a separate paediatric haematology-oncology unit (1·38 [1·21-1·57]; p<0·0001), and having fewer PEWS omissions (0·95 [0·92-0·99]; p=0·0091) were associated with a greater reduction in clinical deterioration event mortality after PEWS implementation; no association was found with country income level (IRR 0·86 [95% CI 0·68-1·09]; p=0·22) or clinical deterioration event rates before PEWS implementation (1·04 [0·97-1·12]; p=0·29). INTERPRETATION: PEWS implementation was associated with reduced clinical deterioration event mortality in paediatric patients with cancer across 32 resource-limited hospitals in Latin America. These data support the use of PEWS as an effective evidence-based intervention to reduce disparities in global survival for children with cancer. FUNDING: American Lebanese Syrian Associated Charities, US National Institutes of Health, and Conquer Cancer Foundation. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Acidic patch histone mutations and their effects on nucleosome remodeling.

Structural and biochemical studies have identified a histone surface on each side of the nucleosome disk termed 'the nucleosome acidic patch' that acts as a regulatory hub for the function of numerous nuclear proteins, including ATP-dependent chromatin complexes (remodelers). Four major remodeler subfamilies, SWI/SNF, ISWI, CHD, and INO80, have distinct modes of interaction with one or both nucleosome acidic patches, contributing to their specific remodeling outcomes. Genome-wide sequencing analyses of various human cancers have uncovered high-frequency mutations in histone coding genes, including some that map to the acidic patch. How cancer-related acidic patch histone mutations affect nucleosome remodeling is mainly unknown. Recent advances in in vitro chromatin reconstitution have enabled access to physiologically relevant nucleosomes, including asymmetric nucleosomes that possess both wild-type and acidic patch mutant histone copies. Biochemical investigation of these substrates revealed unexpected remodeling outcomes with far-reaching implications for alteration of chromatin structure. This review summarizes recent findings of how different remodeler families interpret wild-type and mutant acidic patches for their remodeling functions and discusses models for remodeler-mediated changes in chromatin landscapes as a consequence of acidic patch mutations.

A Vietnamese human genetic variation database.

Large scale human genome projects have created tremendous human genome databases for some well-studied populations. Vietnam has about 95 million people (the 14th largest country by population in the world) of which more than 86% are Kinh people. To date, genetic studies for Vietnamese people mostly rely on genetic information from other populations. Building a Vietnamese human genetic variation database is a must for properly interpreting Vietnamese genetic variants. To this end, we sequenced 105 whole genomes and 200 whole exomes of 305 unrelated Kinh Vietnamese (KHV) people. We also included 101 other previously published KHV genomes to build a Vietnamese human genetic variation database of 406 KHV people. The KHV database contains 24.81 million variants (22.47 million single nucleotide polymorphisms (SNPs) and 2.34 million indels) of which 0.71 million variants are novel. It includes more than 99.3% of variants with a frequency of >1% in the KHV population. Noticeably, the KHV database revealed 107 variants reported in the human genome mutation database as pathological mutations with a frequency above 1% in the KHV population. The KHV database (available at https://genomes.vn) would be beneficial for genetic studies and medical applications not only for the Vietnamese population but also for other closely related populations.