Survival in primary hemophagocytic lymphohistiocytosis, 2016 to 2021: etoposide is better than its reputation.

ABSTRACT: Primary hemophagocytic lymphohistiocytosis (pHLH) is a life-threatening hyperinflammatory syndrome that develops mainly in patients with genetic disorders of lymphocyte cytotoxicity and X-linked lymphoproliferative syndromes. Previous studies with etoposide-based treatment followed by hematopoetic stem cell transplantation (HSCT) resulted in 5-year survival of 50% to 59%. Contemporary data are lacking. We evaluated 88 patients with pHLH documented in the international HLH registry from 2016-2021. In 12 of 88 patients, diagnosis was made without HLH activity, based on siblings or albinism. Major HLH-directed drugs (etoposide, antithymocyte globulin, alemtuzumab, emapalumab, ruxolitinib) were administered to 66 of 76 patients who were symptomatic (86% first-line etoposide); 16 of 57 patients treated with etoposide and 3 of 9 with other first-line treatment received salvage therapy. HSCT was performed in 75 patients; 7 patients died before HSCT. Three-year probability of survival (pSU) was 82% (confidence interval [CI], 72%-88%) for the entire cohort and 77% (CI, 64%-86%) for patients receiving first-line etoposide. Compared with the HLH-2004 study, both pre-HSCT and post-HSCT survival of patients receiving first-line etoposide improved, 83% to 91% and 70% to 88%. Differences to HLH-2004 included preferential use of reduced-toxicity conditioning and reduced time from diagnosis to HSCT (from 148 to 88 days). Three-year pSU was lower with haploidentical (4 of 9 patients [44%]) than with other donors (62 of 66 [94%]; P < .001). Importantly, early HSCT for patients who were asymptomatic resulted in 100% survival, emphasizing the potential benefit of newborn screening. This contemporary standard-of-care study of patients with pHLH reveals that first-line etoposide-based therapy is better than previously reported, providing a benchmark for novel treatment regimes.

Clinical trio genome sequencing facilitates the interpretation of variants in cancer predisposition genes in paediatric tumour patients.

The prevalence of pathogenic and likely pathogenic (P/LP) variants in genes associated with cancer predisposition syndromes (CPS) is estimated to be 8-18% for paediatric cancer patients. In more than half of the carriers, the family history is unsuspicious for CPS. Therefore, broad genetic testing could identify germline predisposition in additional children with cancer resulting in important implications for themselves and their families. We thus evaluated clinical trio genome sequencing (TGS) in a cohort of 72 paediatric patients with solid cancers other than retinoblastoma or CNS-tumours. The most prevalent cancer types were sarcoma (n = 26), neuroblastoma (n = 15), and nephroblastoma (n = 10). Overall, P/LP variants in CPS genes were identified in 18.1% of patients (13/72) and P/LP variants in autosomal-dominant CPS genes in 9.7% (7/72). Genetic evaluation would have been recommended for the majority of patients with P/LP variants according to the Jongmans criteria. Four patients (5.6%, 4/72) carried P/LP variants in autosomal-dominant genes known to be associated with their tumour type. With the immediate information on variant inheritance, TGS facilitated the identification of a de novo P/LP in NF1, a gonadosomatic mosaic in WT1 and two pathogenic variants in one patient (DICER1 and PALB2). TGS allows a more detailed characterization of structural variants with base-pair resolution of breakpoints which can be relevant for the interpretation of copy number variants. Altogether, TGS allows comprehensive identification of children with a CPS and supports the individualised clinical management of index patients and high-risk relatives.

Defibrotide for the Treatment of Pediatric Inflammatory Multisystem Syndrome Temporally Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection in 2 Pediatric Patients.

The pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 infection is a severe complication of coronavirus disease 2019. Since impaired coagulation and thrombosis/endotheliitis are suspected pathomechanisms, we treated 2 patients with defibrotide, a profibrinolytic, antithrombotic, antiinflammatory oligonucleotide. Symptoms resolved during treatment. Moreover, coagulation parameters indicating hypofibrinolysis and complement activation normalized. The pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 infection is a severe complication of coronavirus disease 2019. Since impaired coagulation and thrombosis/endotheliitis are suspected pathomechanisms, 2 patients received defibrotide, a profibrinolytic, antithrombotic, antiinflammatory oligonucleotide. Symptoms resolved and hypofibrinolysis/complement activation normalized during treatment.

Clinical characteristics and outcome of 60 pediatric patients with malignant melanoma registered with the German Pediatric Rare Tumor Registry (STEP).

Background Malignant melanoma (MM) is a common malignancy in adults while it is rare in children. Thus, information on clinical behavior of pediatric MM is incomplete. Patients The German Pediatric Rare Tumor Registry (STEP) presents a prospective analysis of 60 childhood MM cases diagnosed between June 2006 and December 2014. Method Patients' ages ranged between 0 and 17 years at initial diagnosis (median age 9.6 years). Information on patient's and tumor characteristics was obtained by standardized documentation. Three-year overall survival (OS) and event-free survival (EFS) were estimated by the Kaplan-Meier test. Results Follow-up ranged from 0 to 116 months with a median of 36.5 months, however, univariate analysis was performed for 46 cases with a follow-up > 3 months, only. Cases with spitzoid histotype (40%) did not show a significantly different outcome compared to cases with non-spitzoid MM. Breslow thickness ≤ 2.00 mm was identified in 30% of the cases and 18% were Clark level I to III. Adjuvant therapy was used in 45% of cases. OS at 3 years was 100%, EFS 95.2%. Conclusion We present a series of cases with a high number of spitzoid malignant melanoma and advanced pediatric melanoma, but surprisingly good overall survival rates. Spitzoid and non-spitzoid MM do not differ in clinical behavior and survival.

Does human bocavirus infection depend on helper viruses? A challenging case report.

A case of severe diarrhoea associated with synergistic human bocavirus type 1 (HBoV) and human herpes virus type 6 (HHV6) is reported. The case supports the hypotheses that HBoV infection under clinical conditions may depend on helper viruses, or that HBoV replicates by a mechanism that is atypical for parvoviruses, or that HBoV infection can be specifically treated with cidofovir.

Parenteral nutrition is not superior to replacement fluid therapy for the supportive treatment of chemotherapy induced oral mucositis in children.

Many paediatric oncology centres apply parenteral nutrition (PN) in children with severe oral mucositis after chemotherapy. However, no convincing data exist to support this treatment strategy. The aim of our study was to elucidate a possible advantage of PN versus intravenous replacement fluid therapy (FT). In a prospective randomized study, 30 children with mucositis WHO grade IV were assigned to receive either PN or intravenous replacement FT. Weight, total body water, fat-free mass (measured by impedance analysis) and peripheral white blood cells were assessed daily. For aspects of quality of life and economics, the length of hospital stay, the incidence of infections, the days on intravenous antibiotics and delay of scheduled chemotherapy were examined. Children with PN gained body weight significantly compared to baseline and to FT due to an augmentation of fat mass while total body water and fat-free mass significantly decreased. In children with FT, body weight remained stable while total body water and fat-free mass significantly increased, thereby loosing fat mass. We observed no differences in recovery of peripheral white blood cells (WBC), incidence of infections, hospitalization time, days on intravenous antibiotics, days on opioid analgesics and delay of the next scheduled chemotherapy cycle. Although children with PN gained weight in form of fat mass, this did not translate into a clinical benefit for the patients such as earlier recovery of WBC counts, shorter hospitalization time, a decreased use of analgesics or less delay of the next scheduled chemotherapy cycle. Our findings therefore do not support the hypothesis that PN is superior to FT when used for less than 10 days for oral mucositis.

Age-related reference values for serum selenium concentrations in infants and children.

BACKGROUND: Children are at particular risk for selenium deficiency, which has potentially serious medical implications. Reliable age-specific reference values for serum selenium concentrations in children are sparse, but are essential for the identification of selenium deficiency and decisions regarding selenium supplementation. METHODS: Using electrothermal atomic absorption spectrometry, we analyzed serum selenium concentrations from 1010 apparently healthy children (age range, 1 day to 18 years) and from 60 patients on a protein-restricted diet because of inborn errors of metabolism. Reference intervals were defined according to recommended guidelines. RESULTS: Medians for serum selenium concentrations showed a statistically significant age dependency: a decrease from the age <1 month (0.64 micromol/L) to 4 months (0.44 micromol/L); an increase to 0.62 micromol/L in the 4-12 months age group; constant values in children between 1 and 5 years of age (0.90 micromol/L); and an additional slight increase to reach a plateau between 5 and 18 years (0.99 micromol/L). Of 43 children older than 1 year and on a protein-restricted diet, 87% showed serum selenium concentrations below the 2.5 percentile. CONCLUSIONS: Because of nutritional changes, serum selenium concentrations are significantly higher in older children than in infants under 1 year of age. The application of age-adjusted reference values may provide more specific criteria for selenium supplementation. Long-term protein restriction in children is reflected by a failure to achieve higher serum selenium concentrations with increasing age.