Allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) represents a potentially curative strategy for many oncological, hematological, metabolic, and immunological diseases in children. The continuous effort in ameliorating supportive care represents one of the cornerstones in the improvement of outcome in these patients. Nowadays, more than ever nutritional support can be considered a key feature. Oral feeding in the early post-transplant period is severely impaired because of mucositis due to conditioning regimen, characterized by, mainly by vomiting, anorexia, and diarrhea. Gastrointestinal acute graft-versus-host-disease (GvHD), infections and associated treatments, and other medications, such as opioids and calcineurin inhibitors, have also been correlated with decreased oral intake. The consequent reduction in caloric intake combined with the catabolic effect of therapies and transplantation-related complications with consequent extended immobilization, results in a rapid deterioration of nutritional status, which is associated with decreased overall survival and higher complication rates during treatment. Thus, nutritional support during the early post-transplantation period becomes an essential and challenging issue for allo-HSCT recipients. In this context, the role of nutrition in the modulation of the intestinal flora is also emerging as a key player in the pathophysiology of the main complications of HSCT. The pediatric setting is characterized by less evidence, considering the challenge of addressing nutritional needs in this specific population, and many questions are still unanswered. Thus, we perform a narrative review regarding all aspects of nutritional support in pediatric allo-HSCT recipients, addressing the assessment of nutritional status, the relationship between nutritional status and clinical outcomes and the evaluation of the nutritional support, ranging from specific diets to artificial feeding.

ERCC excision repair 6 like 2 (ERCC6L2) gene encodes for different helicase-like protein members of the Snf2 family involved in transcription-coupled nucleotide excision repair and in cell proliferation. Germline homozygous mutations in children and adults predispose to a peculiar bone marrow failure phenotype characterized by mild hematological alterations with a high risk of developing acute myeloid leukemia. The outcome for patients with leukemia progression is dismal while patients undergoing hematopoietic stem cell transplantation in the early stage have better outcomes. The ERCC6L2-related hematological disease presents a high penetrance, posing important questions regarding the treatment strategies and possible preemptive approaches. This review describes the biological function of ERCC6L2 and the clinical manifestations of the associated disease, trying to focus on the unsolved clinical questions.

Pediatric acute myeloid leukemia (AML) represents an aggressive disease and is the leading cause of childhood leukemic mortality. The genomic landscape of pediatric AML has been recently mapped and redefined thanks to large-scale sequencing efforts. Today, understanding how to incorporate the growing list of genetic lesions into a risk stratification algorithm for pediatric AML is increasingly challenging given the uncertainty regarding the prognostic impact of rare lesions. Here we review some uncommon cytogenetic lesions to be considered for inclusion in the high-risk groups of the next pediatric AML treatment protocols. We describe their main clinical characteristics, biological background and outcome. We also provide some suggestions for the management of these rare but challenging patients and some novel targeted therapeutic options.

Despite improvements in therapeutic protocols and in risk stratification, acute myeloid leukemia (AML) remains the leading cause of childhood leukemic mortality. Indeed, the overall survival accounts for ~70% but still ~30% of pediatric patients experience relapse, with poor response to conventional chemotherapy. Thus, there is an urgent need to improve diagnosis and treatment efficacy prediction in the context of this disease. Nowadays, in the era of high throughput techniques, AML has emerged as an extremely heterogeneous disease from a genetic point of view. Different subclones characterized by specific molecular profiles display different degrees of susceptibility to conventional treatments. In this review, we describe in detail this genetic heterogeneity of pediatric AML and how it is linked to relapse in terms of clonal evolution. We highlight some innovative tools to characterize minor subclones that could help to enhance diagnosis and a preclinical model suitable for drugs screening. The final ambition of research is represented by targeted therapy, which could improve the prognosis of pediatric AML patients, as well as to limit the side toxicity of current treatments.