Challenges in Treating Pediatric Cancer Patients during the COVID-19 Pandemic: Balancing Risks and Care.

The COVID-19 pandemic has resulted in millions of fatalities worldwide. The case of pediatric cancer patients stands out since, despite being considered a population at risk, few studies have been carried out concerning symptom detection or the description of the mechanisms capable of modifying the course of the COVID-19 disease, such as the interaction and response between the virus and the treatment given to cancer patients. By synthesizing existing studies, this paper aims to expose the treatment challenges for pediatric patients with COVID-19 in an oncology context. Additionally, this updated review includes studies that utilized the antiviral agents Remdesivir and PaxlovidTM in pediatric cancer patients. There is no specific treatment designed exclusively for pediatric cancer patients dealing with COVID-19, and it is advisable to avoid self-medication to prevent potential side effects. Managing COVID-19 in pediatric cancer patients is indeed a substantial challenge. New strategies, such as chemotherapy application rooms, have been implemented for children with cancer who were positive for COVID-19 but asymptomatic since the risk of disease progression is greater than the risk of complications from SARS-CoV-2.

Genetic Markers as Predictors for Response to Treatment and Possible Therapeutic Targets in Medulloblastoma.

BACKGROUND: Medulloblastomas (MB) are the most common malignant brain tumors in the pediatric age. In 2021, WHO categorized medulloblastomas into two groups: molecularly defined and histologically defined medulloblastomas. Molecularly defined medulloblastomas are divided into WNTactivated medulloblastoma, SHH-activated and TP53-wildtype medulloblastoma, SHH-activated, and TP53-mutant and non-WNT/non-SHH medulloblastoma, which include Group 3 (MYC) and Group 4 (CDK6 and MYCN). In this paper, we will focus on molecularly defined medulloblastomas. OBJECTIVE: This paper aims to review the literature in order to describe the molecular structure of the medulloblastoma groups and to emphasize the importance of genetic predictors in medulloblastoma that can be used in clinical practice, either as a prognostic tool or as a therapeutic target in the future. RESULTS: Each molecular subtype of medulloblastoma presents a different prognosis, and the molecular subtype with the best prognosis is medulloblastoma-activated WNT. It has even been observed that a reduction in the intensity of the combined treatment does not modify the prognosis of the patients, resulting in even fewer adverse effects due to the treatment. On the other hand, it was observed that the subtypes with the worst prognosis are medulloblastomas with activated MYC and medulloblastomas with activated SHH and mutated TP53, due to their high capacity to metastasize or to their radio-resistance. However, a new target therapy has emerged that could help improve the prognosis in these patients. CONCLUSION: The deeper knowledge of the molecular pathways involved in the appearance and progression of medulloblastomas will allow us to offer a prognosis at the time of diagnosis and more specific treatments through the development of the targeted therapy.

Clinical characteristics and mortality predictors of patients with cancer hospitalized by COVID-19 in a pediatric third-level referral center.

Background: More than 135 million COVID-19 cases (coronavirus disease 2019) have been reported worldwide until today, with over 2.9 million deaths. Several studies have demonstrated that disease severity is lower in the pediatric population than in adults; however, differences are described in patients with chronic diseases, including oncological patients. Current world literature suggests patients with comorbidities, including cancer, have an increased risk of unfortunate outcomes. Therefore, our objective was to describe the clinical characteristics and epidemiological factors associated with mortality in a cohort of pediatric cancer patients hospitalized for COVID-19. Methods: This is a retrospective, descriptive study of the cases of patients with cancer hospitalized for COVID-19. A total of 40 pediatrics were included in the analysis. Data from pediatric patients with COVID-19 included clinical and epidemiological records, laboratory, imaging studies, COVID-19 diagnostic methods, and medical treatment. Results: Of the 40 pediatric patients admitted with cancer with a confirmed diagnosis of COVID-19, 42.5% were solid tumors, 40% leukemias, and 17.5% lymphomas. The clinical parameters associated with mortality were stage IV tumor (p = 0.029) and intubation (p < 0.001). The biochemical factors associated with lower survival were thrombocytopenia under 25,000 cells/mm3 (p < 0.001), D-dimer over 1 µg/ml (p = 0.003), clinical malnutrition (p = 0.023), and disseminated intravascular coagulation (p = 0.03). Conclusion: Our findings showed that the fever was the most frequent symptom, and the clinical parameters associated with mortality were stage IV tumor, intubation, saturation percentage, RDW, platelets, creatinine, ALT, D-dimer, ferritin, and FiO2 percentage. The thrombocytopenia, D-dimer, nutritional status, and disseminated intravascular coagulation were significantly associated with lower survival.

Changes in the neutrophil to lymphocyte ratio as predictors of outcome in pediatric patients with central nervous system tumors undergoing surgical resection.

BACKGROUND: Changes in neutrophil to lymphocyte ratio (ΔNLR) have been used as a clinical tool for stratification and prognosis of patients with solid tumors, there is scarce evidence of their clinical relevance in patients with tumors of the central nervous system who have also undergone surgical resection. OBJECTIVE: Determine if (ΔNLR) are associated with poor response to treatment and worse prognosis in pediatric patients with central nervous system tumors (CNST) who underwent surgical resection. METHODS: We performed a retrospective cohort study; demographic, clinical, and hematological variables were evaluated, Kaplan-Meier survival curves and Cox proportional hazards regression model were performed to evaluate prognosis. RESULTS: The ΔNLR cutoff value obtained through the third interquartile range was 4.30; The probability of survival and complete response to treatment was different between patients with high ΔNLR when compared to patients with low ΔNLR (p= 0.013, p=≪ 0.001, respectively). A high ΔNLR behaved as an independent predictor of worse Overall Survival (HR 2,297; 95% CI: 1,075-4.908, p= 0.032). CONCLUSION: An elevated ΔNLR was a predictor of poor response to treatment and a prognostic factor for worse Overall Survival in pediatric patients with CNST undergoing surgical resection.

Immunothrombosis in COVID-19: Implications of Neutrophil Extracellular Traps.

SARS-CoV-2 is a member of the family of coronaviruses associated with severe outbreaks of respiratory diseases in recent decades and is the causative agent of the COVID-19 pandemic. The recognition by and activation of the innate immune response recruits neutrophils, which, through their different mechanisms of action, form extracellular neutrophil traps, playing a role in infection control and trapping viral, bacterial, and fungal etiological agents. However, in patients with COVID-19, activation at the vascular level, combined with other cells and inflammatory mediators, leads to thrombotic events and disseminated intravascular coagulation, thus leading to a series of clinical manifestations in cerebrovascular, cardiac, pulmonary, and kidney disease while promoting severe disease and mortality. Previous studies of hospitalized patients with COVID-19 have shown that elevated levels of markers specific for NETs, such as free DNA, MPO, and H3Cit, are strongly associated with the total neutrophil count; with acute phase reactants that include CRP, D-dimer, lactate dehydrogenase, and interleukin secretion; and with an increased risk of severe COVID-19. This study analyzed the interactions between NETs and the activation pathways involved in immunothrombotic processes in patients with COVID-19.