Corrigendum: Second malignant neoplasms within 5 years from first primary diagnosis in pediatric oncology patients in Canada: a population-based retrospective cohort study.

[This corrects the article DOI: 10.3389/fonc.2024.1376652.].

Second malignant neoplasms within 5 years from first primary diagnosis in pediatric oncology patients in Canada: a population-based retrospective cohort study.

Introduction: From the advancement of treatment of pediatric cancer diagnosis, the five-year survival rate has increased significantly. However, the adverse consequence of improved survival rate is the second malignant neoplasm. Although previous studies provided information on the incidence and risk of SMN in long term survivors of childhood cancer, there is still scarce information known for short term (< 5 years) prognosis. This study aims to assess the incidence, characteristics, management, and outcome of children who develop SMN malignancies within 5 years of diagnosis of their initial cancer. Method: This is a retrospective cohort study of early Second Malignant Neoplasms (SMN) in pediatric oncology patients. The Cancer in Young People - Canada (CYP-C) national pediatric cancer registry was used and reviewed pediatric patients diagnosed with their first cancer from 2000-2015. Results: A total of 20,272 pediatric patients with a diagnosis of a first malignancy were analyzed. Of them, 0.7% were diagnosed with a SMN within the first 5 years following their first cancer diagnosis. Development of a SMN impacted survival, shown by an inferior survival rate in the SMN cohort (79.1%) after three years compared to that of the non-SMN cohort (89.7%). Several possible risk factors have been identified in the study including the use of epipodophyllotoxins, exposure to radiation, and hematopoietic stem cell 169 transplant. Discussion: This is the first national study assessing the incidence, 170 characteristics, risk factors and outcome of early SMN in Canadian children 171 from age 0-15 from 2000-2015.

Risk factors and clinical impact of thrombosis during induction chemotherapy for pediatric acute lymphoblastic leukemia: A report from CYP-C.

Thromboembolism (TE) is associated with reduced survival in pediatric acute lymphoblastic leukemia (ALL). It has been hypothesized that TE might signal leukemic aggressiveness. The objective was to determine risk factors for TE during ALL induction (TEind ) therapy and whether TEind is associated with treatment refractoriness. This retrospective cohort study using the population-based Cancer in Young People Canada (CYP-C) registry included children <15 years of age diagnosed with ALL (2000-2019) and treated at one of 12 Canadian pediatric centers outside of Ontario. Univariate and multivariable logistic regression models were used to determine risk factors for TEind and whether TEind predicted induction failure and ALL treatment intensification. The impact of TEind on overall and event-free survival was estimated using Cox proportional hazard regression models. The study included 2589 children, of which 45 (1.7%) developed a TEind . Age (<1 year and ≥10 years vs. 1-<10 years), T-cell phenotype, high-risk ALL, and central nervous system involvement were all associated with TEind in univariate analysis. Age and T-cell phenotype remained independent predictors of TEind in multivariable analysis. Induction failure occurred in 53 patients (2.1%). TEind was not associated with induction failure (OR: not estimable) or treatment intensification (adjusted OR [95% CI]: 0.66 [0.26-1.69]). TEind was independently associated with overall survival (adjusted HR [95% CI]: 2.54 [1.20-5.03]) but not event-free survival (adjusted HR [95% CI] 1.86 [0.98-3.51]). In this population-based study of children treated with contemporary chemotherapy protocols, TEind was associated with age and T-cell phenotype and mortality but did not predict induction failure.

French Canadian cross-cultural adaptation of CAPTSure©, an index for the Clinical Assessment of Post-Thrombotic Syndrome in children.

PURPOSE: Post-thrombotic syndrome (PTS) is the most common complication of deep venous thrombosis (DVT). The index for the Clinical Assessment of Post-Thrombotic Syndrome in children (CAPTSure©) is a clinical tool for the diagnosis and severity rating of PTS in pediatric patients. The purpose of this study was to translate and adapt CAPTSure© for French-speaking patients. METHODS: We conducted a cross-sectional study to perform linguistic and cultural adaptation of CAPTSure©, using a rigorous translation process followed by cognitive debriefings in twenty French-speaking pediatric patients aged up to 18 years old with a history of upper or lower extremity DVT at least 6 months prior. RESULTS: Forward and backward translations were used to produce a pre-final French version of CAPTSure©, followed by cognitive debriefings in twenty participants (median age: 11.5 years, 55% male, median CAPTSure© score: 26). The participants felt that the questionnaire was thorough, with an adequate length. Eight out of fourteen (57%) items in the LE questionnaire and 7/12 (58%) of the items in the UE questionnaire were modified following participants' and a multidisciplinary expert committee's input, leading to the final French version of CAPTSure©. CONCLUSIONS: CAPTSure© was successfully adapted for French-speaking pediatric patients. This will ease the diagnosis and severity rating of PTS in children in clinical practice and allow international research collaborations for additional non-English-speaking patients.

Between Scylla and Charybdis: thrombosis in children with hemophilia.

Thromboembolism is an infrequent complication in children with hemophilia that has been traditionally associated with the presence of a central venous access device. Novel rebalancing agents have shown promising results as prophylactic therapies to minimize the risk of bleeding but both thromboembolism and thrombotic microangiopathy have been reported as complications. The management of thrombosis in children with hemophilia is particularly challenging given the inherent risk of bleeding. In this paper, we present clinical vignettes to review the literature, highlight challenges, and describe our approach to managing thromboembolism in children with hemophilia.

Biomarkers in pediatric venous thromboembolism: a systematic review of the literature.

BACKGROUND: Accurate prediction of the individual risk of venous thromboembolism (VTE) remains suboptimal in children, and biomarkers are currently not used to stratify the risk of VTE in children. OBJECTIVES: This study aimed to assess which biological or radiological biomarkers may predict VTE or VTE complications in children. PATIENTS/METHODS: A literature search was performed for peer-reviewed publications (1990-2022). We included studies addressing the use of biomarkers for patients aged 29 days to 18 years to predict VTE or its complications, including but not limited to TE-related death, VTE recurrence, or postthrombotic syndrome. Given the heterogeneity of the study designs, populations, and outcomes, no quantitative data synthesis was performed. RESULTS: Forty studies were included, totaling 10,987 participants (median age: 4.7 years). Reports were often lacking critical methodological data, including blood collection method (68% of studies) and timepoints, laboratory testing technique (41%), or primary outcome definition (20%). Forty-six individual biomarkers were assessed for VTE prediction (32 studies, 9525 participants), including d-dimers, fibrinogen, platelet count, white blood cell count, and factor VIII. Albumin, C-reactive protein, d-dimers, factor VIII, and thrombin-antithrombin levels showed promising results for VTE prediction. In 9 studies (1606 participants), no biomarker was consistently predictive of postthrombotic syndrome, VTE persistence, or VTE recurrence in children. CONCLUSIONS: Several candidate biomarkers were promising in the prediction of VTE in children. Still, discrepancies between different studies and the high risk of bias from the current literature prevent their widespread use in the clinical setting. Further prospective research in various pediatric subpopulations is required.

Very Early Diagnosis and Management of Congenital Erythropoietic Porphyria.

Congenital erythropoietic porphyria (CEP), a rare form of porphyria, is caused by a defect in the heme biosynthesis pathway of the enzyme uroporphyrinogen III synthase (UROS). Uroporphyrinogen III synthase deficiency leads to an accumulation of nonphysiological porphyrins in bone marrow, red blood cells, skin, bones, teeth, and spleen. Consequently, the exposure to sunlight causes severe photosensitivity, long-term intravascular hemolysis, and eventually, irreversible mutilating deformities. Several supportive therapies such as strict sun avoidance, physical sunblocks, red blood cells transfusions, hydroxyurea, and splenectomy are commonly used in the management of CEP. Currently, the only available curative treatment of CEP is hematopoietic stem cell transplantation (HSCT). In this article, we present a young girl in which precocious genetic testing enabled early diagnosis and allowed curative treatment with HSCT for CEP at the age of 3 months of age, that is, the youngest reported case thus far.

COVID-19-associated coagulopathy in children: A multicenter observational cohort study.

SARS-CoV-2 infection (coronavirus disease 2019 [COVID-19]) induces a stark procoagulant state, with many hospitalized adults developing thrombosis despite prophylactic anticoagulation. This study aimed to characterize hemostatic parameters and associated clinical outcomes of COVID-19, such as thrombosis and bleeding, in children and to assess thromboprophylaxis use. This multicenter observational cohort study included 79 patients aged up to 18 years admitted to all pediatric hospitals in Québec, Canada, with SARS-CoV-2 infection during a 5-month period. D-dimers were elevated in 18/19 patients (94.7%) and fibrinogen in 15/26 patients (60%). Eleven patients (13.9%) received anticoagulant thromboprophylaxis. One thrombotic event and one major bleed were observed.

Prognostic factors and outcomes of infant acute lymphoblastic leukemia (ALL), hypodiploid ALL, and mixed-phenotype acute leukemia (MPAL) in Canada: a report from CYP-C.

The epidemiology of infant acute lymphoblastic leukemia (ALL), hypodiploid ALL, and mixed-phenotype acute leukemia (MPAL) in Canada is unknown. The main objective was to describe the prevalence, prognostic factors, and outcomes of three rare and high-risk ALL subtypes in Canada. This is a retrospective study using the Cancer in Young People-Canada (CYP-C) database. Event-free survival (EFS) and overall survival (OS) were described by the Kaplan-Meier method and compared using the log-rank test. Among 2626 children aged 0-14 years diagnosed with B-cell acute lymphoblastic leukemia (B-ALL) between 2001 and 2018, 227 (8.6%) patients were identified to be infant ALL (n = 139), hypodiploid ALL (n = 43), or MPAL (n = 45). The 5-year EFS/OS was significantly worse in the infant ALL subgroup compared to that of hypodiploid ALL and MPAL. For the entire cohort, presenting White blood cells (WBCs) ≥50 × 109/L was independently associated with worse EFS/OS.

Post-procedural bleeding rate and haemostatic treatment use for dental procedures before and after the implementation of a standardized protocol for people with inherited bleeding disorders.

INTRODUCTION: Persons with inherited bleeding disorders are at a substantial risk of bleeding following dental procedures. AIM: To compare the outcomes and use of haemostatic treatment pre- and post-implementation of a standardized protocol for dental procedures at a Hemophilia Treatment Centre. METHODS: We conducted a retrospective cohort study of outpatient and inpatient dental procedures and maxillofacial surgeries sustained by people with bleeding disorders treated at a comprehensive Hemophilia Treatment Centre (2013-2020), comparing patients' outcomes before and after the introduction of the protocol in 2018. The protocol, built using a multidisciplinary approach, suggested haemostatic treatment based on the invasiveness of the dental procedure and the proposed anaesthesia. Our primary outcome was the rate of procedural bleeding leading to medical or dental reintervention within 10 days. Secondary outcomes included the use of systemic haemostatic treatment and treatment-related adverse effects. RESULTS: Overall, 137 dental procedures in 95 patients (median age: 29 years; 78% males; 74% haemophilia, 14% von Willebrand disease, 12% other disorders) were included. Seventeen procedural bleedings were reported (12.4%). Procedural bleeding occurred in 14.8% and 8.9% of patients in the control and intervention groups (p = .304). No major bleeding occurred. Tranexamic acid was used more consistently after protocol implementation (72.8% vs. 89.3%, p = .019), while factor concentrates use decreased (65.4% vs. 44.6%, p = .016), and desmopressin use remained constant (46.4% vs. 32.1%, p = .100). No treatment-related adverse effects were reported. CONCLUSION: The use of a standardized protocol increased the use of tranexamic acid, with a nonstatistically significant reduction in procedural bleeding rate.

Acute Management of High-Risk and Intermediate-Risk Pulmonary Embolism in Children: A Review.

Severe forms of pulmonary embolism (PE) in children, althought rare, cause significant morbidity and mortality. We review the pathophysiologic features of severe (high-risk and intermediate-risk) PE and suggest novel pediatric-specific risk stratifications and an acute treatment algorithm to expedite emergent decision-making. We defined pediatric high-risk PE as causing cardiopulmonary arrest, sustained hypotension, or normotension with signs or symptoms of shock. Rapid primary reperfusion should be pursued with either surgical embolectomy or systemic thrombolysis in conjunction with a heparin infusion and supportive care as appropriate. We defined pediatric intermediate-risk PE as a lack of systemic hypotension or compensated shock, but with evidence of right ventricular strain by imaging, myocardial necrosis by elevated cardiac troponin levels, or both. The decision to pursue primary reperfusion in this group is complex and should be reserved for patients with more severe disease; anticoagulation alone also may be appropriate in these patients. If primary reperfusion is pursued, catheter-based therapies may be beneficial. Acute management of severe PE in children may include systemic thrombolysis, surgical embolectomy, catheter-based therapies, or anticoagulation alone and may depend on patient and institutional factors. Pediatric emergency and intensive care physicians should be familiar with the risks and benefits of each therapy to expedite care. PE response teams also may have added benefit in streamlining care during these critical events.

Incidence of childhood cancer in Canada during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic has had a major impact on access to health care resources. Our objective was to estimate the impact of the COVID-19 pandemic on the incidence of childhood cancer in Canada. We also aimed to compare the proportion of patients who enrolled in clinical trials at diagnosis, presented with metastatic disease or had an early death during the first 9 months of the COVID-19 pandemic compared with previous years. METHODS: We conducted an observational study that included children younger than 15 years with a new diagnosis of cancer between March 2016 and November 2020 at 1 of 17 Canadian pediatric oncology centres. Our primary outcome was the monthly age-standardized incidence rates (ASIRs) of cancers. We evaluated level and trend changes using interventional autoregressive integrated moving average models. Secondary outcomes were the proportion of patients who were enrolled in a clinical trial, who had metastatic or advanced disease and who died within 30 days. We compared the baseline and pandemic periods using rate ratios (RRs) and 95% confidence intervals (CIs). RESULTS: Age-standardized incidence rates during COVID-19 quarters were 157.7, 164.6, and 148.0 per million, respectively, whereas quarterly baseline ASIRs ranged between 150.3 and 175.1 per million (incidence RR 0.93 [95% CI 0.78 to 1.12] to incidence RR 1.04 [95% CI 0.87 to 1.24]). We found no statistically significant level or slope changes between the projected and observed ASIRs for all new cancers (parameter estimate [ß], level 4.98, 95% CI -15.1 to 25.04, p = 0.25), or when stratified by cancer type or by geographic area. Clinical trial enrolment rate was stable or increased during the pandemic compared with baseline (RR 1.22 [95% CI 0.70 to 2.13] to RR 1.71 [95% CI 1.01 to 2.89]). There was no difference in the proportion of patients with metastatic disease (RR 0.84 [95% CI 0.55 to 1.29] to RR 1.22 [0.84 to 1.79]), or who died within 30 days (RR 0.16 [95% CI 0.01 to 3.04] to RR 1.73 [95% CI 0.38 to 15.2]). INTERPRETATION: We did not observe a statistically significant change in the incidence of childhood cancer, or in the proportion of children enrolling in a clinical trial, presenting with metastatic disease or who died early during the first 9 months of the COVID-19 pandemic, which suggests that access to health care in pediatric oncology was not reduced substantially in Canada.

Thrombosis is associated with worse survival in children with acute lymphoblastic leukemia: A report from CYP-C.

There are conflicting data about whether the development of cancer-associated thrombo-embolism (TE) negatively impacts survival in children. The objective was to determine whether TE during treatment was associated with overall survival (OS) and event-free survival (EFS) in children with acute lymphoblastic leukemia (ALL). We performed a population-based retrospective cohort study using the Cancer in Young People-Canada registry. Children <15 years of age were diagnosed with de novo ALL (2000-2016). The primary exposure variable was radiologically-confirmed thrombo-embolism requiring medical intervention. Multivariable Cox regression models were used to determine the impact of thrombo-embolism on survival, where TE was time-dependent. We included 2006 children (median age: 4 years, 88.5% precursor B-cell ALL). Thrombo-embolism occurred in 113 patients (5.6%), at a median time of 107 days (interquartile range: 35-184 days) after ALL diagnosis. Among standard/low-risk patients, 41/1165 (3.5%) developed TE while among high/very high-risk patients, 72/841 (8.6%) developed TE. Patients with TE had a significantly worse OS (adjusted HR [aHR] of death: 2.61, 95% CI: 1.62-4.22, p < 0.001) and EFS (aHR of an event [death, relapse, second malignancy]: 2.03, 95% CI: 1.35-3.05, p = 0.001), compared with patients without TE. No statistically significant difference was seen in standard/low risk ALL for OS and EFS, but TE was associated with a significantly lower OS and EFS in children with high/very high-risk ALL (aHR of death: 2.90, 95% CI: 1.79-4.72, p < 0.001; aHR of an event: 2.02, 95% CI: 1.30-3.12, p = 0.002). Thus, TE led to a statistically significant reduction in OS and EFS in children with high risk/very high-risk leukemia.

Distance to the pediatric oncology center does not affect survival in children with acute lymphoblastic leukemia: a report from CYP-C.

Remoteness is associated with worse survival in adults with cancer. We aimed to determine whether remoteness is associated with cancer outcomes in pediatric acute lymphoblastic leukemia (ALL). Canadian children with ALL entered in the CYP-C registry were included. The predictive impact of remoteness on overall survival (OS), relapse, and treatment-related complications (infections, thrombosis, bleeding, and osteonecrosis) was estimated using multivariate regression models. We included 1383 children, of whom 277 (20.0%) lived remotely (>200 km from the pediatric oncology center). The median latency to see a pediatric oncologist was longer in children living remotely. The 5-year OS (95% CI) was similar for both groups (remote: 95.2% [93.7-96.3%] vs close: 94.1% [90.5-95.2%]). No difference was found in the relapse rate between both groups and in treatment-related complications. Remoteness did not affect survival in pediatric ALL. Further research is needed to determine which models of healthcare organization optimize cancer outcomes and patients' satisfaction.