EBV-driven lymphoid neoplasms associated with pediatric ALL maintenance therapy.

The development of a second malignancy after the diagnosis of childhood acute lymphoblastic leukemia (ALL) is a rare event. Certain second malignancies have been linked with specific elements of leukemia therapy, yet the etiology of most second neoplasms remains obscure and their optimal management strategies are unclear. This is a first comprehensive report of non-Hodgkin lymphomas (NHLs) following pediatric ALL therapy, excluding stem-cell transplantation. We analyzed data of patients who developed NHL following ALL diagnosis and were enrolled in 12 collaborative pediatric ALL trials between 1980-2018. Eighty-five patients developed NHL, with mature B-cell lymphoproliferations as the dominant subtype (56 of 85 cases). Forty-six of these 56 cases (82%) occurred during or within 6 months of maintenance therapy. The majority exhibited histopathological characteristics associated with immunodeficiency (65%), predominantly evidence of Epstein-Barr virus-driven lymphoproliferation. We investigated 66 cases of post-ALL immunodeficiency-associated lymphoid neoplasms, 52 from our study and 14 additional cases from a literature search. With a median follow-up of 4.9 years, the 5-year overall survival for the 66 patients with immunodeficiency-associated lymphoid neoplasms was 67.4% (95% confidence interval [CI], 56-81). Five-year cumulative risks of lymphoid neoplasm- and leukemia-related mortality were 20% (95% CI, 10.2-30) and 12.4% (95% CI, 2.7-22), respectively. Concurrent hemophagocytic lymphohistiocytosis was associated with increased mortality (hazard ratio, 7.32; 95% CI, 1.62-32.98; P = .01). A large proportion of post-ALL lymphoid neoplasms are associated with an immunodeficient state, likely precipitated by ALL maintenance therapy. Awareness of this underrecognized entity and pertinent diagnostic tests are crucial for early diagnosis and optimal therapy.

Childhood leukemia and non-Hodgkin's lymphoma survivors lack knowledge about their past disease and possible late effects. I-BFM ELTEC study with Chilean and Croatian participation.

PURPOSE: Late effects in childhood cancer survivors are a major cause of morbidity and mortality. The objective was to establish knowledge about the disease, late effects, self-care practices, application of health knowledge/education, sources of information, and biopsychosocial impact of cancer, and compare the results of Chile and Croatia. METHODS: One-hundred-and-seventy-one, 5-year survivors who were treated for leukemia or non-Hodgkin's lymphoma responded to a questionnaire (119 in Chile and 52 in Croatia). The questionnaire was reviewed by BFM-ELTEC. RESULTS: Health knowledge about past diagnosis and general treatment had 96% Chilean and 85% Croatian survivors. Ninety percent of Chilean and 73% of Croatian survivors were unaware of possible late effects, and half did not know which specialist to visit for follow-up. Forty-six percent of Chilean and 35% of Croatian survivors knew about healthy lifestyles, but most did not practice them. The 74% of Chileans and 87% of Croatian survivors recalled having received health education during treatment. About 50% of survivors in both groups were afraid or anguish, but it was also a growth experience for 60% of Chilean and 42% of Croatian survivors. Eighty-seven percent Chilean and 77% Croatian survivors considered themselves physically independent, while 76% and 75% felt psychologically independent, respectively. CONCLUSION: A significant lack of knowledge about the specific treatment, late effects, and future health in both countries was detected. They did not achieve significant learning with the education received. Psychological sequelae were found that are important to prevent.

Epigenetic footprint enables molecular risk stratification of hepatoblastoma with clinical implications.

BACKGROUND & AIMS: Hepatoblastoma (HB) is a rare disease. Nevertheless, it is the predominant pediatric liver cancer, with limited therapeutic options for patients with aggressive tumors. Herein, we aimed to uncover the mechanisms of HB pathobiology and to identify new biomarkers and therapeutic targets in a move towards precision medicine for patients with advanced HB. METHODS: We performed a comprehensive genomic, transcriptomic and epigenomic characterization of 159 clinically annotated samples from 113 patients with HB, using high-throughput technologies. RESULTS: We discovered a widespread epigenetic footprint of HB that includes hyperediting of the tumor suppressor BLCAP concomitant with a genome-wide dysregulation of RNA editing and the overexpression of mainly non-coding genes of the oncogenic 14q32 DLK1-DIO3 locus. By unsupervised analysis, we identified 2 epigenomic clusters (Epi-CA, Epi-CB) with distinct degrees of DNA hypomethylation and CpG island hypermethylation that are associated with the C1/C2/C2B transcriptomic subtypes. Based on these findings, we defined the first molecular risk stratification of HB (MRS-HB), which encompasses 3 main prognostic categories and improves the current clinical risk stratification approach. The MRS-3 category (28%), defined by strong 14q32 locus expression and Epi-CB methylation features, was characterized by CTNNB1 and NFE2L2 mutations, a progenitor-like phenotype and clinical aggressiveness. Finally, we identified choline kinase alpha as a promising therapeutic target for intermediate and high-risk HBs, as its inhibition in HB cell lines and patient-derived xenografts strongly abrogated tumor growth. CONCLUSIONS: These findings provide a detailed insight into the molecular features of HB and could be used to improve current clinical stratification approaches and to develop treatments for patients with HB. LAY SUMMARY: Hepatoblastoma is a rare childhood liver cancer that has been understudied. We have used cutting-edge technologies to expand our molecular knowledge of this cancer. Our biological findings can be used to improve clinical management and pave the way for the development of novel therapies for this cancer.

Evaluation of metabolic syndrome after hematopoietic stem cell transplantation in children and adolescents.

BACKGROUND: To determine the prevalence, characteristics, and risk factors associated with metabolic syndrome (MS) in patients undergoing hematopoietic stem cell transplantation (HSCT) in the Chilean National Program. PROCEDURES: Descriptive and cross-sectional study including 69 patients was conducted. Body mass index, pubertal development, waist circumference, arterial pressure (AP), and triglycerides, HDL-cholesterol, and glucose levels were recorded at the time of study entry. The National Cholesterol Education Program (Adult Treatment Panel III, as modified by the American Heart Association) criteria are often used to diagnose MS in adults; however, for children and adolescents we followed criteria according to De Ferranti and American Diabetes Association. Statistical analyses were performed with a chi-square test or Fisher's exact test according to sample size. RESULTS: Sixty-nine patients were studied. The median age at the time of diagnosis was 12.9 years, and the median time of follow-up post-transplant was 4 years. Forty-three patients were males, 54 patients had malignant diseases, and 59 patients received allogeneic transplants. Of the 69 patients, 32% had MS; the most common MS features were abdominal obesity (73%), hypertriglyceridemia (91%), and a low HDL-cholesterol level (96%). The most significant risk factor for MS was corticosteroid therapy use pre- (P < 0.03) and post-HSCT (P < 0.03), obesity and overweight associated with MS (P < 0.001). No patient developed cardiovascular complications. CONCLUSIONS: The prevalence of MS was 32%, which was significantly higher than in a healthy pediatric population. We recommend prolonged follow-up for transplant recipients, coupled with enforcement of preventive measures, such as early diagnosis and encouragement of a healthy lifestyle.

Haploidentical stem cell transplantation for children with high-risk leukemia.

BACKGROUND: The Chilean population is ethnically diverse, and more than 50% of children referred for hematopoietic stem cell transplantation (HSCT) lack a suitable donor. PROCEDURE: To expand the donor pool, we assessed the feasibility, tolerance, and efficacy of using a haploidentical (HI) donor and a reduced-intensity conditioning regimen for high-risk pediatric leukemia. This study was facilitated by technology transfer from St. Jude Children's Research Hospital over the 2 preceding years. RESULTS: Between March 2006 and April 2009, 10 patients (median age, 9.8 years) received T cell-depleted grafts at Calvo Mackenna Hospital in Santiago. Median cell doses were CD34+: 7.45 × 10(6)/kg (range, 4.00-20.20 × 10(6)/kg); CD3+: 0.88 × 10(5)/kg (0.11-1.35 × 10(5)/kg); and CD56+: 71.30 × 10(6)/kg (31.50-131.80 × 10(6)/kg). Nine patients experienced complete engraftment; six of the nine remain alive and clinically well 13-50 months post-HSCT. Three patients died after bone marrow relapse, while only one died of transplant-related causes. Virus reactivation was the main post-transplant complication: 5/10 had positive CMV PCR but none had CMV disease. One patient developed acute GvHD > grade II and only one had chronic GvHD. CONCLUSIONS: HI-HSCT is feasible in our setting, offers a rational treatment option, and expands the donor pool significantly for children with high-risk leukemia in a developing country. This information is especially relevant to other ethnically diverse populations that are poorly represented in international donor registries.

[Ovarian reserve and premature ovarian failure in girls and adolescents after hematopoietic stem cell transplantation]. / Reserva ovárica y falla ovárica prematura en niñas y adolescentes postrasplante de progenitores hematopoyéticos.

INTRODUCTION: The increased survival of children and adolescents after Stem Cell Transplantation (SCT) has allowed us to gain a better understanding of the late effects that this procedure might have. OBJECTIVE: to measure ovarian function and reserve after SCT. PATIENTS AND METHOD: A descriptive, observatio nal, and cross-sectional study of girls and adolescents with SCT between 1999 and 2011. External gynecologic examination, hormone tests, and abdominal gynecologic ultrasound were performed, observing pubertal development pre-SCT. The following data from the clinical record were recorded: baseline pathology, type of conditioning, use of radiotherapy in conditioning, age at the time of SCT, and history of acute or chronic graft-versus-host disease (GVHD). Hormonal tests included follicle- stimulating hormone (FSH), luteinizing hormone (LH), estradiol, prolactin (PRL), thyroid-stimula ting hormone (TSH), free thyroxine, total testosterone, sex hormone-binding globulin (SHBG), and anti-Müllerian hormone (AMH). Statistical analysis included the chi-square or Fisher's Exact test with a p-value < 0.05. RESULTS: 41 patients were evaluated. The median age at the time of SCT was 6.8 years (1.5-14.1) and the median age at evaluation was 14.8 years (range: 4-25.4 years). 93% of the transplants were in patients with oncological disease and with myeloablative conditioning regimens. All patients presented decreased ovarian reserve, and 72% showed Premature Ovarian Failure (POF). CONCLUSIONS: All patients had decreased ovarian reserve and most of them had a high prevalence of POF. Before SCT, a gynecological evaluation and subsequent follow-up for hormone monitoring and initiation of hormone replacement are essential.

Cytomegalovirus infection in children undergoing hematopoietic stem cell transplantation in Chile.

BACKGROUND: Cytomegalovirus (CMV) infection remains as an important cause of morbidity and mortality in children undergoing hematopoietic stem cell transplantation (HSCT). Our aim was to assess the incidence, risk factors, and outcome related to CMV infection in children after HSCT in a developing country. METHODS: From October 1, 1999, to December 31, 2005, we prospectively studied all patients admitted to the HSCT unit at Hospital Luis Calvo Mackenna in Santiago, Chile. Serologic studies before transplantation and weekly CMV infection surveillance (antigenemia or quantitative PCR) were routinely obtained. Patients with positive antigenemia or quantitative PCR received pre-emptive therapy with ganciclovir, and cases of unfavorable clinical evolution, persistent positive antigenemia, or quantitative PCR after 14 days of ganciclovir were treated with foscarnet. RESULTS: Ninety-seven patients received HSCT. Their median age was 8 years (range, 3 months to 24 years) and their overall survival was 67%. CMV reactivation was diagnosed in 26 patients. Of these, three developed CMV disease (two interstitial pneumonia, one hemorrhagic cystitis). One of the patients with pneumonia died. Risk factors identified were pre-transplant serologic status (positive recipient), acute and chronic graft versus host disease (GvHD), GvHD prophylaxis, and treatment with antithymocyte globulin. CONCLUSIONS: The rate and prognosis of CMV infection among children treated at our HSCT unit is similar to those reported from industrialized countries. These findings reflect adequate prevention and management of CMV infection within our program.

Efficacy of irinotecan single drug treatment in children with refractory or recurrent hepatoblastoma--a phase II trial of the childhood liver tumour strategy group (SIOPEL).

PURPOSE: To assess the clinical activity of irinotecan as single drug in children with refractory or recurrent hepatoblastoma. PATIENTS AND METHODS: Four cycles of irinotecan were administered (20mg/m(2)/day intravenous (i.v.) infusion on days 1-5 and 8-12, every 21days) unless tumour progression occurred or resectability was achieved earlier. Tumour response was assessed according to modified SIOPEL and Response Evaluation Criteria In Solid Tumours (RECIST) criteria. Main end-points were best overall response rate (RR), early progression rate (EPR) and progression free survival (PFS). RESULTS: Twenty-four eligible patients (median age 58.0months; 19 boys) were enrolled in the study (11 relapses, 13 refractory diseases). Of the 23 evaluable patients six had an overall partial response, 11 stable disease and six progressive disease, of which four were early progression (RR: 26%, EPR: 17%). In eight patients the residual tumour could be completely resected; seven patients became tumour free. At last follow-up 12 patients were alive (six with no evidence of disease, six with disease). PFS at 1year was 24%. Patients with relapse had a higher RR than patients with refractory disease (46% versus 8%) and patients with isolated lung lesions showed a better response than patients with other tumour localisations (50% versus 13%). The main grade 3-4 toxicities, diarrhoea and neutropenia, occurred in half of the patients. CONCLUSION: Irinotecan has a significant anti-tumour activity and acceptable toxicity in patients with relapsed hepatoblastoma and therefore should be considered for the treatment of these patients. Exploration of the role of irinotecan in the initial treatment of hepatoblastoma is warranted.

Establishment of a pediatric HSCT program in a public hospital in Chile.

BACKGROUND: In Chile, survival estimates for pediatric patients with cancer are comparable to those in the United States and Western Europe. Approximately 80% of these patients are treated at government-supported centers, and an estimated 65% are cured. We reasoned that cure rates could be further improved if transplantation with hematopoietic stem cells were available for patients with chemotherapy-resistant malignancy. PATIENTS AND METHODS: Physicians and nurses were selected to be trained in international centers, and a transplantation unit was developed at Luis Calvo Mackenna Hospital in Santiago. Between October 1999 and December 2003, 59 patients received transplants. Of these, 42 were from HLA-matched family members and 11 were autologous. RESULTS: The 3-year event-free survival estimate was 72 +/- 10% overall, and it was 81 +/- 10% for the subgroup treated with matched related transplants. Peritransplant mortality was 6.6%. The average cost for an allogeneic transplant in our unit was 50,000 US dollars. CONCLUSIONS: We are encouraged by this experience as well as by the overall survival rates and hope to expand the program. Our goal is to extend treatment to all children in the country for whom HSCT is indicated, including those who do not have HLA-identical family donors.

Seroprevalencia de citomegalovirus y toxoplasma gondii en población sana menor de 30 años, en Santiago de Chile / Seroprevalence of cytomegalovirus y toxoplasma gondii in health population under 30 years old at Santiago, Chile

Subjects and methods: The prevalence of IgG antibodies against Cytomegalovirus and Toxoplasma gondii were studied in 560 subjetcs under 30 years old, using and ELISA technique. Age, socioeconomic level, breast feeding, assistance to nurseries and number of family members were considered as risk factors for these infections. Results: Infection by Cytomegalovirus and Toxoplasma gondii were studied in 560 subjetcs under 30 years old, using an ELISA technique. Age, socioeconomic level, breast feeding, assistance to nurseries and number of family members were considered as risk factors for these infections. Results: Infection by Cytomegalovirus had a global prevalence of 60 percent. It showed an epidemiological pattern of late adquisition in high socioeconomic levels and a pattern of early infection in medium and low socioeconomic levels. Eighty to 90 percent of sera were positive for the infection in adult subjetcs of the three socioeconomic levels. There was a positive correlation between the duration of breast feeding and the frequency of Cytomegalovirus infection. Infection by Toxoplasma gondii had a global prevalence of 24.6 percent. The rates of susceptible individuals were 80 and 50 percent in high and medium-low socioeconomic levels respectively. Conclusions: The knowledge about the frequency of these infections in high risk populations such as women during their reproductive years and immunodepressed individuals, will allow the implementation of preventive measures