Skin Biopsy in Pediatric Oncology/Hematopoietic Stem Cell Transplantation Patients.

ABSTRACT: The aim of this study was to review the dermatopathological findings in skin biopsy specimens from pediatric oncology and hematopoietic stem cell transplantation patients over a 20-year period. Three hundred fifty-two skin biopsies from 240 patients were reviewed, and the findings were grouped into 6 categories: index neoplasms, nonindex neoplasms, infections, graft-versus-host disease, other treatment complications, and others. Among the index neoplasms identified on skin biopsy, the most common conditions were Langerhans cell histiocytosis (14 patients) and melanoma (7 patients), with other hematological malignancies and an array of soft-tissue tumors accounting for the bulk of the remainder. Neoplastic conditions common in general dermatopathological practice such as basal cell carcinoma and squamous cell carcinoma were uncommon, each being identified in only 1 patient younger than the age of 18, although basal cell carcinomas developing subsequently in young adult life were identified in 7 patients. Infections were common, with infectious agents or viral cytopathic effects (not including human papillomavirus) identified in 34 biopsies. A significant proportion (74%) represented invasive fungal infections, which are of very significant clinical importance. Biopsies performed for a clinical suspicion of graft-versus-host seldom showed histological features to suggest an alternative diagnosis, with only a single case suggesting a diagnosis of toxic erythema of chemotherapy identified.

Optimized peripheral blood progenitor cell mobilization for autologous hematopoietic cell transplantation in children with high-risk and refractory malignancies.

BACKGROUND: Autologous hematopoietic stem cell transplantation (aHSCT) using hematopoietic progenitor cells (HPCs) has become an important therapeutic modality for patients with high-risk malignancies. Current literature on standardized method for HPC apheresis in children is sparse and failure rate reported as high as 30%. PATIENTS/METHODS: A retrospective study of 125 pediatric patients with high-risk malignancies undergoing aHSCT in Western Australia between 1997 and 2016 was conducted. RESULTS: Mobilization was achieved by means of chemotherapy and granulocyte colony-stimulating factor (G-CSF). Patients underwent apheresis the day after CD34+ counts reached ≥20/µL and an additional dose of G-CSF. Peripheral arterial and intravenous lines were inserted in pediatric intensive care unit under local anesthetic and/or sedation, omitting the need for general anesthesia as well as facilitating an uninterrupted apheresis flow. Larger apheresis total blood volumes were processed in patients weighing ≤20 kg. The minimal dose of ≥2 × 106 CD34+ cells/kg was successfully collected in 98.4% of all patients. The optimal dose of 3-5 × 106 CD34+ cells/kg was collected in 96% of patients scheduled for a single aHSCT, 87.5% for tandem, and 100% for triple aHSCT. All HPC collections were completed in one apheresis session. Mobilization after ≤3 chemotherapy cycles and cycles including cyclophosphamide resulted in a significantly higher yield of CD34+ cells. CONCLUSION: Our approach to HPC mobilization by means of chemotherapy and single myeloid growth factor combined with optimal collection timing facilitated by continuous apheresis flow resulted in highly effective HPC harvest in children and adolescents with high-risk cancers.

Vaccine-preventable disease following allogeneic haematopoietic stem cell transplant in Western Australia.

AIM: Infection is an important and frequent cause of mortality and morbidity following allogeneic haematopoietic stem cell transplantation (HSCT). This study was conducted to determine the epidemiology and clinical phenotype of vaccine-preventable disease in children who have undergone HSCT following the implementation of a standard revaccination programme. METHODS: Children receiving first allogeneic HSCT in Western Australia between January 2005 and December 2014 were eligible for recruitment. Patients received standard antimicrobial prophylaxis and were vaccinated according to the West Australian post-HSCT immunisation schedule, commencing 6 months following HSCT. Children who developed any illness post-HSCT were reviewed, and investigations for infectious disease were undertaken as clinically indicated. Positive identification of vaccine-preventable disease was documented with the clinical course of the illness. RESULTS: A total of 71 patients were enrolled in the study. The overall incidence of vaccine-preventable disease following HSCT was 19.7%; influenza accounted for 50% of all cases, herpes zoster for 42.9%. All episodes occurred late, beyond day 100 post-HSCT. Overall survival for matched-sibling donor transplants was 83.3 and 75.0% at 1 and 5 years, respectively, and was 72.3 and 63.3% for alternative donor transplants. Mortality due to vaccine-preventable disease was low, with one death from disseminated herpes zoster. CONCLUSIONS: There is a high incidence of vaccine-preventable morbidity post-allogeneic HSCT in West Australian children. Viral aetiology constitutes the main burden, namely, influenza infection and varicella zoster virus reactivation. Further efforts are required to identify the most appropriate preventative strategies.

Increased Body Mass Index during Therapy for Childhood Acute Lymphoblastic Leukemia: A Significant and Underestimated Complication.

Objective & Design. We undertook a retrospective review of children diagnosed with acute lymphoblastic leukemia (ALL) and treated with modern COG protocols (n = 80) to determine longitudinal changes in body mass index (BMI) and the prevalence of obesity compared with a healthy reference population. Results. At diagnosis, the majority of patients (77.5%) were in the healthy weight category. During treatment, increases in BMI z-scores were greater for females than males; the prevalence of obesity increased from 10.3% to 44.8% (P < 0.004) for females but remained relatively unchanged for males (9.8% to 13.7%, P = 0.7). Longitudinal analysis using linear mixed-effects identified associations between BMI z-scores and time-dependent interactions with sex (P = 0.0005), disease risk (P < 0.0001), age (P = 0.0001), and BMI z-score (P < 0.0001) at diagnosis and total dose of steroid during maintenance (P = 0.01). Predicted mean BMI z-scores at the end of therapy were greater for females with standard risk ALL irrespective of age at diagnosis and for males younger than 4 years of age at diagnosis with standard risk ALL. Conclusion. Females treated on standard risk protocols and younger males may be at greatest risk of becoming obese during treatment for ALL. These subgroups may benefit from intervention strategies to manage BMI during treatment for ALL.