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Hematopoietic stem cell transplantation is a widely used therapy for different diseases in the pediatric population. Haploidentical transplantation with negative immunoselection using electromagnetic fields is an alternative for those patients without an HLA-matched donor. Twenty pediatric patients under 18 years old received a haploidentical CD3+/CD19+-depleted transplant due to the absence of an HLA-matched donor. The mean age at which HSCT was performed was 6.6 years (range 1-18 years), and clinical indications were: acute lymphoblastic leukemia (9 patients), primary immunodeficiency (8 patients), acute myeloid leukemia (2 patients), and severe aplastic anemia (1 patient). The medium dose of cells infused was 10.9 (min. 2, max. 32) x 106/kg CD34+ cells, 3.2-4.1 x 105/kg CD3+ cells and 2.4-3.7 x 105/kg CD19+ cells. Results: Eleven of the twenty patients had donor engraftment (55%) and had complete chimera of their donors. From this group, nine (45%) developed primary graft failure, and four (36%) developed graft-versus-host disease. In the group of leukemia patients, overall survival was 75% while event-free survival was 40%. Haploidentical transplantation with negative immunoselection is a useful and feasible strategy for children without an ideal donor. In our cohort, patients with acute leukemia had better outcomes than patients with non-malignant diseases.

The evidence supporting the biological plausibility of the association of permethrin and malathion with hematological cancer is limited and contradictory; thus, further studies are needed. This study aimed to investigate whether in vitro exposure to 0.1 μM permethrin and malathion at 0, 24, 48 and 72 h after cell culture initiation induced changes in the gene expression and DNA methylation in mononuclear cells from bone marrow and peripheral blood (BMMCs, PBMCs). Both pesticides induced several gene expression modifications in both tissues. Through gene ontology analysis, we found that permethrin deregulates ion channels in PBMCs and BMMCs and that malathion alters genes coding proteins with nucleic acid binding capacity, which was also observed in PBMCs exposed to permethrin. Additionally, we found that both insecticides deregulate genes coding proteins with chemotaxis functions, ion channels, and cytokines. Several genes deregulated in this study are potentially associated with cancer onset and development, and some of them have been reported to be deregulated in hematological cancer. We found that permethrin does not induce DNA hypermethylation but can induce hypomethylation, and that malathion generated both types of events. Our results suggest that these pesticides have the potential to modify gene expression through changes in promoter DNA methylation and potentially through other mechanisms that should be investigated.

Human TPI (HsTPI) is a central and essential glycolytic enzyme for energy supply and is overexpressed in cancer cells. Here, we investigated HsTPI as a potential target for inducing cell death in triple-hormone receptor-negative breast cancer, which is highly dependent on glycolysis, and therapies for its treatment are limited. We found endogenous accumulation of deamidated HsTPI in human breast cancer cells, which might be caused by the lower activity of the HsTPI-degrading caspase-1 in breast cancer cells.In silicoandin vitroanalyses of deamidated HsTPI demonstrated the efficacy of thiol-reactive drugs in blocking enzyme activity. The cancer cells were selectively programmed to undergo apoptosis with thiol-reactive drugs by inducing the production of methylglyoxal (MGO) and advanced glycation-end products (AGEs).In vivoin mice, the thiol-reactive drug effectively inhibited the growth of human tumors by targeting HsTPI as underlying mechanism. Our findings demonstrate deamidated HsTPI as a novel target to develop therapeutic strategies for treating cancers and other pathologies in which this post-translationally modified protein accumulates.

Long-term outcomes after allogeneic hematopoietic cell transplantation (HCT) for therapy-related myeloid neoplasms (tMNs) are dismal. There are few multicenter studies defining prognostic factors in pediatric patients with tMNs. We have accumulated the largest cohort of pediatric patients who have undergone HCT for a tMN to perform a multivariate analysis defining factors predictive of long-term survival. Sixty-eight percent of the 401 patients underwent HCT using a myeloablative conditioning (MAC) regimen, but there were no statistically significant differences in the overall survival (OS), event-free survival (EFS), or cumulative incidence of relapse and non-relapse mortality based on the conditioning intensity. Among the recipients of MAC regimens, 38.4% of deaths were from treatment-related causes, especially acute graft versus host disease (GVHD) and end organ failure, as compared to only 20.9% of deaths in the reduced intensity conditioning (RIC) cohort. Exposure to total body irradiation (TBI) during conditioning and experiencing grade III/IV acute GVHD were associated with worse OS. In addition, a diagnosis of therapy related myelodysplastic syndrome and having a structurally complex karyotype at tMN diagnosis were associated with worse EFS. Reduced-toxicity (but not reduced-intensity) regimens might help to decrease relapse while limiting mortality associated with TBI-based HCT conditioning in pediatric patients with tMNs.

Academic pediatric surgery in Mexico has many challenges and opportunities. Work life balance, health service delivery and committements to our many students and residents must be tailored to goals and aspirations respecting talent at every opportunity when we encounter it. This article offers a perspective on the landscape and how we can shape the future in our nation to embrace new leadership in academic pediatric surgery.

Background: Acute graft-versus-host disease (aGVHD) is the most frequent and severe complication after allogeneic hematopoietic stem cell transplantation (HSCT). Objective: To determine if a history of prior infection in the allogeneic HSTC recipient is a risk factor to develop aGVHD. Methods: A retrospective cohort study based on data collected from the Department of Hematopoietic Stem Cell Transplantation at the Instituto Nacional de Pediatria (INP) from January 1998 to December 2016 was performed to identify if prior infection was a predictive risk factor for aGVHD. Results: 27 patients developed aGVHD (36.4%). Median time to aGVHD presentation was 82 days (9 to 273 days). Most patients developed grade III aGVHD. Following the multivariate analysis peripheral blood > bone marrow (OR 12.3; p 8.3 × 106/kg (OR 7.1; p = 0.05), peripheral blood (OR: 11.4; p < 0.001), infection 3 months prior to allogeneic transplant (OR: 4.5; p < 0.03) and CMV infection in the recipient (OR: 4.68; p < 0.03) were significant. Conclusions: Either bacterial infection or CMV infection in the recipient was significant risk factor within the aGVHD recipients; it is important to consider these factors for patients that are going to receive an allogeneic HSCT.

Purpose Limited data describe the delivery of pediatric cancer care in Mexico. We report a nationwide survey of pediatric cancer units. Methods An electronic survey was distributed to 74 pediatric cancer units in Mexico to describe case volumes; organization of care; and availability of medical/surgical specialists, supportive care, complex therapies, and diagnostic services. Centers were classified as low (< 30 new patients/year), medium (30 to 59/year) and high (≥ 60/year). Results Sixty-two centers completed the survey (response rate, 84%). The median annual new case volume per center was 50 (interquartile range [IQR], 23 to 81). Thirty-four percent (n = 21), 26% (n = 16), and 40% (n = 25) of units were low-, medium-, and high-volume centers, respectively. Treatment units reported a median of two pediatric oncologists (IQR, 2) and one pediatric hematologist (IQR, 1 to 2). Availability of medical and surgical subspecialists varied by center size, with substantially more specialist support at higher-volume centers ( P < .01). Multidisciplinary tumor boards are available at 29% (six of 21), 56% (nine of 16), and 76% (19 of 25) of low- to high-volume centers, respectively ( P = .005). Radiation and palliative care services are available at 42% (n = 26) and 63% (n = 36) of all centers, which did not vary by center volume. Educational support for hospitalized children and school reintegration programs are available at 56% (n = 36) and 58% (n = 36) of centers, respectively. One third (38% [n = 23]) of centers reported that at least one half of patients were lost to follow-up during the transition from pediatric to adult programs. Conclusion A large variation exists in annual case volumes across Mexican pediatric cancer centers. Additional efforts to increase access to multidisciplinary, supportive, and palliative care across all pediatric cancer units in Mexico are required.

Acute lymphoblastic leukemia (ALL), the most common type of cancer in children worldwide, has one of the highest incidence rates in Mexico. It is a multifactorial disease and different cytokine single nucleotide polymorphisms (SNP), have been associated with ALL expression. Few studies have been published analyzing IFNG +874 T/A and IL2 −330 G/T in this type of leukemia. These SNPs are involved in high or low expression, and are central to cellular immunity, influencing greatly tumor growth. The purpose of this work was to explore the association of IFNG +874 A/T (rs2430561) and IL2 −330 G/T (rs2069762) SNPs with ALL susceptibility and/or protection in 488 Mexican Mestizos patients, as compared to 950 Mexican Mestizo healthy controls. The results demonstrated that IFNG +874 T allele (pc = 0.00004, OR = 0.673) and the TT genotype (pc = 0.00015, OR = 0.349), protect against ALL expression with no specific gender association; however, the TT homozygote genotype (vs. TA+AA) seems more protective in males (pc = 0.00683). IL2 −330 G/T does not contribute to the development of ALL. In healthy Mexicans, the most common genotypes for IL2 and IFNG, are the low cytokine producers, suggesting that the genetic background in this ethnic group, may be partly responsible for the high incidence of ALL. These results show for the first time in Mexicans, the relevant role that IFNG SNP has in the genetic etiology of ALL. Thus, a large group of patients belonging to different ethnicities will be very helpful to study in order to demonstrate if these SNPs contribute to the genetic etiology of ALL, as shown here in Mexican Mestizos.

Mature B-cell non-Hodgkin lymphoma (B-NHL) comprises more than 50% of all non-Hodgkin lymphoma (NHL) in children and adolescents. An official report published by the Mexican National Center for the Control and Prevention of Cancer in the Pediatric and Adolescent Populations, reported a lymphoma OS of 71% (including all Hodgkin and NHL). The Mexican Association of Pediatric Oncology and Hematology conducted a retrospective study to analyze the clinical characteristics and outcomes of children with diagnosis of B-NHL in Mexico, in order to perceive the main areas of improvement in the health care.From 1 January 2000 to 31 December 2016, 166 pediatric patients were diagnosed with B-cell NHL at the participant institutions.According to histology the outcomes were 5-year EFS 63%, for BL/BLL, and 80% DLBCL, (P = .051), 5-year PFS 81%, for BL/BLL, and 91% for DLBCL, (P = .126), and 5-year OS 71%, for BL/BLL, and 83% for DLBCL, (P = .095).Overall, 18 patients died due to acute treatment toxicity, resulting in a cumulative incidence of toxic death of 10.84% and an early death rate of 7.23%, defined as30 days after initial treatment. In conclusion, there is an urgent need to establish an academic collaboration to create strategies to improve pediatric cancer care according to our resources, especially in diseases with expected excellent prognosis as B-NHL. These strategies must include comprehensive supportive care, early referral, and the creation of easy communication between pediatric and adults centers as well as late-effects clinics.

Introduction Therapy-related myelodysplastic syndrome and acute myeloid leukemia (t-MDS/AML) are rare but well-recognized complications of cancer therapy. Allogeneic hematopoietic cell transplantation (HCT) with myeloablative conditioning (MAC) remains the mainstay of treatment but is associated with a high incidence of non-relapse mortality (NRM). Reduced intensity conditioning (RIC) may reduce NRM in these heavily pre-treated patients. The primary objective of this study was to compare outcomes following RIC and MAC regimens in patients receiving an allogeneic HCT. Methods Retrospective chart review of patients Results One hundred and forty-seven patients were included with 29 (19.7%) receiving RIC and 115 (78.2%) MAC (Table 1). The median follow-up of entire cohort was 13.4 (0-246) months. OS and EFS of the entire cohort was 44.7% (95% CI: 37.1-53.9) and 40.2% (95% CI: 32.8-49.3) at 3 years, respectively, and there was no significant difference between MAC and RIC cohorts (Fig A & B). Karnofsky performance status of the patients (>=90) was the only factor that was found to be statistically associated with improved EFS (HR 0.49, p=0.01). NRM was noted in 61% of patients after MAC compared to 28% after RIC, however disease relapse was a major cause of death after RIC (Fig C & D). The majority of transplants were performed after 2005 (81.6%) and outcomes seem to be slightly better in contemporary era due to improved supportive care and decreased NRM. Conclusion This is one of the largest reported cohorts of pediatric patients receiving allogeneic transplantation for t-MDS/AML. Outcomes are poor relative to de novo MDS/AML due to high rate of NRM with MAC and high rate of disease related death after RIC. Novel strategies that lead to a reduction in transplant-related mortality in these heavily pre-treated patients while providing sufficient disease control are needed to improve survival in t-MDS/AML patients receiving HCT.

Total body irradiation (TBI) is conditioning regimen in children with acute lymphoblastic leukemia (ALL) with a very high risk of relapse or in those who have not achieved remission and have relapsed and subsequently received allogenic hematopoietic stem cell transplantation (HSCT). A retrospective evaluation of 33 ALL patients in full remission with an indication of HSCT was performed to evaluate overall survival (OS) and event-free survival (EFS). The inclusion criteria included a myeloablative conditioning regimen of TBI at a dose of 600 cGy. The observed OS at 5 years was 50%, and the EFS of 32% we observed difference in the EFS stem cell origin; the peripheral blood (PB) 60%, and the umbilical cord blood (UC) accounted for 40%. Overall, 45% had a documented chimerism. The OS at 5 years from patients with chimeras was 75%, while those without chimeras had an OS at 5 years of 25%. The mortality in the first 100 days was 24%. A total of 24.2% of children presented with acute graft versus-host disease (GVHD), while 33% had chronic GVHD. Currently, there is no general agreement among all international centers regarding the optimum TBI dose. Our study reports an acceptable range of adverse events with a relatively low dose of 600 cGy.

Background: In Mexico, AML survival is referred in 30%. Our aim was to evaluate results with ADE protocol as induction treatment in children with non-M3 AML in a public Mexican institution. Method: We included patients with AML in a single institution between 2005 and 2013. All non-M3-AML patients received ADE as induction therapy (cytarabine 100 mg/m2 in continuous infusion from day 1 to 7, daunorrubicin 30 mg/m2 days 1, 3, 5 and etoposide 100 mg/m2 over days 1 to 5). Patients received antibiotic prophylaxis and strict scheduled appointments to assure adherence and prevent avoidable emergencies. Main Results: Eighteen patients were included. Median age was 106 months. One patient died at diagnosis so 17 were eligible for induction results analysis; eleven needed two cycles and six patients three. Remission rate was 100%. Analyzing non-M3 patients overall survival was 80.2% at 100 months. No fatal complications were observed. Stratifying by number of cycles we observe that patients receiving one ADE cycle had a 0% overall survival at short follow up, with 2 ADE cycles 80% at 100 months and with 3 cycles 100% at 60 months. Conclusion: ADE induction therapy showed improved results in overall survival compared with other standard regimens. Following the protocol we obtained 100% remission. This is an important achievement in our population. Our focus must be to ameliorate maintenance final results. These results should be reproduced in other hospitals in Mexico and other countries.

International audience; X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the gene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic mutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of mutations.

Background Fanconi anemia (FA) is a condition characterized by congenital malformations, low height, and progressive bone marrow failure during childhood, genomic instability and hypersensitivity to DNA cross-linking agents. Bone marrow transplantation (BMT), is currently the only treatment capable to restore normal hematopoiesis and improve survival of these patients. To achieve a successful allogeneic BMT, a normal T-cell immunity reconstitution is required.1,2 Objective To describe the kinetics of immune reconstitution in six patients with FA after BMT, having used a reduce intensity conditioning regimen, well as associated infections during the post-transplant process. Methods We describe the distribution in peripheral blood of CD3+ T lymphocytes, CD16 +/CD56+ NK cells, CD4+ helper T lymphocytes, CD8+ cytotoxic T lymphocytes and CD19+/CD20+ B cells, in six patients with FA, after BMT from an HLA-matching sibling and complete chimerism, on days +90, +120, +150, +180, +210 and +360. The conditioning regimen employed consisted of fludarabine (Flu) 150 mg/m2, cyclophosphamide 20 mg/kg and rabbit anti-thymocyte globulin (r-ATG) 20 mg/kg. Infection was determined by a positive reaction of the DNA polymerase chain to Cytomegalovirus (CMV), Epstein-Barr virus, Adenovirus and BK virus (BKV), as well as galactomannan antigen and antibodies against Candida sp, or positive bacterial cultures. Results We observed different kinetics regarding the recovery of different lymphocyte subpopulations, starting from day +90. CD16+/CD56+ NK cells recovered first, between days 90 and 120, followed by CD8+ T lymphocytes between day +120 and +150, CD19+/CD20+ B cells between day +180 and +210, and finally, CD4+ T lymphocytes starting from day 210. Five patients presented infection in the post-BMT stage. Four patients before +90, developed CMV infection, based on positive reaction of the CMV polymerase chain. All patient responses to ganciclovir therapy and no CMV disease were documented. The fifth patient presented with meningitis due to Lysteria monocitogenes and BKV hemorrhagic cystitis at day +153; this patient had the diagnosis of chronic-graft versus host disase, and was treated with ampicillin, rifampicin and intravenous immunoglobulin, evolving satisfactorily. All patients remain alive and well. Discussion Most patients in our report developed CMV infection, as being reported with FLU and anti-thymocyte globulin combination. We observed a later reconstitution in comparison with patients in whom lower doses of r-ATG ( Conclusion Immunological reconstitution after a BMT in FA patients is determinant for morbidity and mortality, mainly due to opportunistic infections and GVHD. We observed that recovery kinetics of different lymphocyte populations is different in cases in which higher doses of r-GAT are used, also an early detection and prompt treatment of opportunistic infections may be determinant for patient's survival. Conflict-of-interest disclosure: The authors declare they have nothing to disclose. Correspondence: Gerardo López-Hernández. loherge@gmail.com BibliographyOgonek J, Kralj Juric M, Ghimire S, Varanasi PR, Holler E, Greinix H, et al. Immune reconstitution after allogenic hematopoietic stem cell transplantation. Front immunol. 2016; 7 (507):1-15.Smith AR, Wagner JE. Current clinical management of Fanconi anemia. Expert Rev Hematol. 2012; 5 (5): 513-522.Perlingeiro-Beltrame M, Malvezzi M, Bonfim C, Tadeu Covas D, Pasquini R. Immune reconstitution in patients with Fanconi anemia after allogeneic bone marrow transplantation. Cytotherapy. 2014; 0: 1e14. Disclosures No relevant conflicts of interest to declare.

Background Hematopoietic stem cell transplantation (HSCT) is used in pediatric patients with acute leukemia, after a relapse to bone marrow, or in first remission in case of high risk disease. If necessary, 75% of the cases do not have a compatible related donor and it is not always possible to have a compatible unrelated donor or an umbilical cord blood unit. Therefore, using haploidentical alternative donors of hematopoietic stem cells (HSC) is becoming more frequent. Objective The purpose of this is to report the results of haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide (PTCy) in a group of pediatric patients, which lacks a related HLA compatible donor, at the National Pediatrics Institute in México City, México, in the period between January 2012 thru December 2016. Methods We retrospectively reviewed 27 patients´ files Results Fourteen patients (51.6%) presented complete and sustained chimerism. Overall survival is presented in Figure 1. Graft failure occurred (48.1%) more frequently in the group of patients in whom bone marrow was used as a source of HSC (p=0.26). Nine patients with complete chimera, whose HSC source turned out to be PB, presented acute-GVHD III-IV (p = 0.06). Four of the patients whom presented full engraftment died, three of them due to infectious processes (cytomegalovirus pneumonia, AH1N1 pneumonia, abdominal sepsis secondary to intestinal perforation and E. coli sepsis), before +100-day post-transplantation. All these patients presented acute-GVHD III-IV. The fourth patient who died, also the cause was infectious (pulmonary sepsis secondary to Morganella morganii), thirteen months after the transplant and without history of GVHD. Of the thirteen patients who presented primary graft failure, seven of them are alive and without evidence of tumoral activity Discussion Haploidentical transplantation with PTCy is a feasible therapeutic option in pediatric patients with malignant hematological diseases who require a HSCT and do not have a matched sibling or unrelated donor available. Conflict-of-interest disclosure: The authors declare they have nothing to disclose. Correspondence: Gerardo López-Hernández. loherge@gmail.com BibliographyKlein OR, Buddenbaum J, Tucker N, et al. Nonmyeloablative Haploidentical Bone Marrow Transplantation with Post-Transplant Cyclophosphamide for Pediatric and Young Adult Patients with High-Risk Hematologic Malignancies. Biol Blood Marrow Transplant. 2017; 23(2): 325-332.González-Llano O, González-López EE, Ramírez-Cázares AC, et al. Haploidentical peripheral blood stem cell transplantation with posttransplant cyclophosphamide in children and adolescents with hematological malignancies. Pediatr Blood Cancer. 2016; 63: 2033-2037.Robinson TM, O'Donnell PV, Fuchs EJ, Luznik L. Haploidentical bone marrow and stem cell transplantation: experience with post-transplantation cyclophosphamide. Semin Hematol. 2016; 53(2): 90-97.Fuchs EJ, Huang XJ, Miller JS. HLA-haploidentical stem cell transplantation for hematologic malignancies. Biol Blood Marrow Transplant. Biol Blood Marrow Transplant. 2010; 16 (1 Suppl): S57-S63. Disclosures No relevant conflicts of interest to declare.

Background: Philadelphia-like (Ph-like) subtype occurs in 15-20% of children patients diagnosed with precursor B cell (PCB) acute lymphoblastic leukemia (ALL). It is characterized by alterations in kinases and their receptors, affecting signaling pathways such as Jak2-Stat5, class Abl and Ras. It is particularly frequent (35%) in Hispano-Latino high risk PCB-ALL patients, residing in the USA. In Mexico, based on our ethnicity and the poor response to treatment of PCB-ALL pediatric patients, the Ph-like subtype could be frequent. However, this entity is widely variable and the diagnosis is based on genomic methods. In our country the incidence of leukemia is high, 78.1/1,000,000, and 83% of these cases are ALL. Therefore, it is important to detect Ph-like patients using diagnostic methods accessible to Institutions that treat patients with leukemia in our country. Aims: To develop an algorithm adapted to our local capacity for the diagnosis of Ph-like ALL children in Mexico. To determine the frequency of Ph-like patients in two Pediatric Institutions in our country Hypothesis: Ph-like ALL frequency in Mexican children will be higher than that reported in Hispano-Latino PCB-ALL patients. Methods, study design and laboratory studies: Bone marrow samples from 119 PCB-ALL patients (18≤ years old) at diagnosis were studied. Samples were collected at the Instituto Nacional de Pediatría and the Hospital Infantil de México Federico Gómez in Mexico City. Patients with recurrent gene fusions, ETV6-RUNX1, TCF3-PBX1,KMT2A-var and BCR-ABL1, were excluded. The Ph-like status of each patient was determined using molecular and biochemical methods. We analyzed a gene expression signature conformed by the genes: CRLF2, TSPN7, IGJ, PON2, SEMA6A and BMPR1B (q-RT-PCR), and detected the P2RY8-CRLF2 deletion (RT-PCR) in all patients. In those patients with overexpression of CRLF2, but negative to P2RY8-CRLF2, the IGH-CRLF2 rearrangement (FISH) was examined. The positive cases to P2RY8-CRLF2, without overexpression of CRLF2, were analyzed looking for minor subclones (FISH) with the deletion. IKZF1 deletions (nested RT-PCR) were analyzed in all patients. The biochemical studies included CRLF2 protein expression, phosphoflow analysis of Jak2-Stat5, class Abl and Ras targets (flow cytometry). All these assays were performed whenever the cell sample allowed it. Patients with two or more of the following characteristics were considered as Ph-like cases: with overexpression of 50% or more of the expression signature, positive to P2RY8-CRLF2 or IGH-CRLF2, alteration of one or more signaling pathways, with IKZF1 deletions. Results: In 50% (n=74) of patients CRLF2 overexpression was detected, within them 15% were positive to P2RY8-CRLF2 deletion, 17% to IGH-CRLF2 rearrangement, and 18% had an unidentified CRLF2 alteration that cause the overexpression. Within the 50% of cases without CRLF2 overexpression, 18% were positive to the P2RY8-CRLF2 rearrangement. IKZF1 deletion was evaluated in 55 patients and 72% were positive. Results obtained revealed a high frequency of CRLF2 and IKZF1. In 68 patients the gene expression profile was evaluated, 60% presented overexpression of 50% or more genes. The biochemical analysis revealed that 67% (n=42) of patients were positive to CRLF2 protein, 29% (n=21) had abnormal Jak2/Stat5 activation, 34% (n=32) presented abnormal Abl activation, and in 43% (n=7) abnormal Ras activation was detected. Not all the CRLF2 protein positive patients presented Jak2-Stat5 pathway activation (2%). Patients with more than one abnormal pathway were detected (18% with Jak2-Stat5/Abl or Abl/Ras, n=21). Based on our algorithm of analysis, 53% of the analyzed patients present genetic and biochemical characteristics of the Ph-like subtype. Conclusions: The combined methods contributed to identify Ph-like patients, the results demonstrate that the frequency of PCB-ALL children with Ph-like characteristics in Mexican patients is higher compared to other populations. This study demonstrates high frequency of CRLF2 alterations and IKZF1 deletions in PCB-ALL in Mexican population. In our experience, analysis of the pathway activation assays and the identification of CRLF2 and IKZF1 alterations are required to detect Ph-like patients. These results could be useful to stratify the childhood PCB-ALL patients in our country. Acknowledgments: CONACYT: PDCPN-2004/248591; Cátedra 2038. Disclosures No relevant conflicts of interest to declare.

Objectives Hematopoietic stem cell transplantation (HSCT) from a matched sibling donor (MSD) is the preferred initial treatment for children with severe aplastic anemia (SAA). Unfortunately, only about 30% of patients have a suitable human leukocyte antigen-matched sibling. Methods We have analyzed the outcome of 42 patients who received HSCT (22 MSD and 20 alternative donors (AD)) for SAA at the seven major pediatric HSCT centers in Mexico between 2001 and 2013. Results With a median follow-up of 30 months (range, 0.4-144), the 5-year overall survival in children transplanted from MSD was 86.4 + 7.3 vs. 49.5 + 11% for children after AD-HSCT (P = 0.013). The cumulative incidence of treatment-related mortality (TRM) was in the MSD-HSCT 9.1 + 3.9% vs. 47.6 + 9.1% in the AD-HSCT context (P = 0.007). Infectious complications contributed to death (91%) of most patients who received AD-HSCT. Discussion Even when the results of patients given MSD-HSCT are adequate, there is still much room for improvement particularly in children allografted with AD and in the supportive care. The development of an economicwise designed prospective project with MSD or matched unrelated donor HSCTs as a first line of treatment of children with SAA as a unified national trial could address these issues.

Background All the children registered at the National Council for the Prevention and Treatment of Childhood Cancer were analyzed. The rationale for this Federal Government Council is to financially support the treatment of all children registered into this system. All patients are within a network of 55 public certified hospitals nationwide. Methods In the current study, data from 2007 to 2012 are presented for all patients (0–18 years) with a pathological diagnosis of leukemia, lymphoma and solid tumors. The parameters analyzed were prevalence, incidence, mortality, and abandonment rate. Results A diagnosis of cancer was documented in 14,178 children. The incidence was of 156.9/million/year (2012). The median age was 4.9. The most common childhood cancer is leukemia, which occurs in 49.8% of patients (2007–2012); and has an incidence rate of 78.1/million/year (2012). The national mortality rate was 5.3/100,000 in 2012, however in the group between 15 to 18 years it reaches a level of 8.6. Conclusions The study demonstrates that there is a high incidence of childhood cancer in Mexico. In particular, the results reveal an elevated incidence and prevalence of leukemia especially from 0 to 4 years. Only 4.7% of these patients abandoned treatment. The clinical outcome for all of the children studied improved since the establishment of this national program.

BACKGROUND In childhood cancer, consolidation treatment with chemotherapy followed by autologous hematopoietic progenitor stem cell transplantation is currently an accepted treatment modality in patients with high-risk solid tumors or in patients who have relapsed after conventional treatment. OBJECTIVES The objective of this study was to describe the results of transplantation of a group of children who had high-risk solid tumors or relapsed after conventional chemotherapy regimens. METHODS A retrospective analysis was conducted from January 1998 to October 2004 of all children with pathologic diagnoses of high-risk solid tumors or children that had previously relapsed after conventional chemotherapy and that were subsequently submitted to autologous hematopoietic progenitor stem cell transplantation. The analysis included overall survival rates, event-free survival rates, mortality rates and chemotherapy complications. RESULTS Nineteen patients were submitted to this approach. The age range was from 27 to 196 months with a median age of 52 months. The overall survival rate at 100 days was observed in 79%, the three-year event-free survival rate was 63%. The mortality rate secondary to the myeloablative chemotherapy regimen was 21% (n = 4). Only three patients (15.8%) relapsed with tumor progression after transplant. CONCLUSION Autologous hematopoietic progenitor stem cell transplantation is still a successful procedure in patients with solid tumors refractory to conventional chemotherapy.

Prior to 2005, 51% of children in Mexico diagnosed with cancer received no standardized optimal multidisciplinary medical care. A government-subsidized national cancer treatment program was therefore created for these patients and a National Cooperative Childhood Cancer Treatment Group was consequently formed for these patients. Pediatric patients with a proven diagnosis of leukemia, lymphoma or solid tumor and who were registered in the Popular Medical Insurance (PMI) program from January 2007 to December 2010, are described in this report. These patients had been enrolled and registered in one of the 49 nationwide certified medical institutions in Mexico. The national incidence and frequency data for childhood cancers were analyzed for the whole program. At the end of a 4-year study, the analysis revealed that 8,936 children from across Mexico had been diagnosed with cancer. The incidence rate for the PMI patients was 150.3/million/year (2010) for children of 0-18 years. The highest age incidence rate was 51.9 between 0 and 4 years and boys were the predominant group for all types of cancer. The leukemia incidence was 75.3/million/year (2010), and an average frequency of 50.75% throughout the 4 years. The overall mortality rate was measured at 5.4/100,000/year (2010). This study demonstrates a high frequency and incidence of childhood cancer and a beneficial impact of the PMI program over the quality of life in these children.

In Mexico, Central Nervous System (CNS) tumors are the third most common childhood cancers. Medulloblastoma constitutes 20% of the primary CNS tumors and 40% of all cerebellar tumors, the single most common brain tumor among children. It originates over the external granular layer that normally migrates from the vermis to the surface of the cerebellum hemispheres and from there to the deep portions of the internal granular layer. These tumors infiltrate profusely the cerebellar cortex. The dissemination process can occur through the spinal fluid with seeding along the subarachnoidal space and around the spinal chord They eventually produce metastasis mainly to bone, liver, and bone marrow. There is a group of well identified prognostic factors that are relevant for each individual patient and that can be applied for multidisciplinary treatment purposes. The objective of the present review is to emphasize on new research findings and the overall survival that can be achieved with modern treatment programs.

Niño de 4 años de edad con diagnóstico de deficiencia de adhesión leucocitaria tipo 1, postrasplantado de células progenitoras hematopoyéticas en tres ocasiones, las dos primeras con falla primaria de injerto.

The congenital immunodeficiency disorders in which the defect has been clearly traced to the stem cell can be cured with allogeneic stem-cell transplantation (SCT) from an unaffected donor. Widespread application of this treatment modality has been tempered by the fact that risk-benefit considerations do not always favor a procedure that carries a significant risk for morbidity and mortality. Some malignant disorders of childhood eventually have to be treated by an autologous or allogeneic SCT, however nonmalignant disorders can also be treated with this approach. This article reviews the current status of SCT for nonmalignant inherited immunodeficiency disorders.

The graft-versus-tumor effect occurring after allogeneic (genetically different) haematopoietic cell transplantation for treating human malignancies, represents the clearest example of the power of the human immune system to eradicate cancer. Recent advances in our understanding of the immunobiology of stem-cell engraftment, tolerance and tumor eradication are allowing clinicians to better harness this powerful effect.