title: Analysis of pediatric autologous PBSC apheresis and transplant: age is a major factor affecting post-transplant toxicity.
abstract: BACKGROUND
  High-dose chemotherapy followed by autologous hematopoietic cell transplantation (HCT) is used in many therapeutic protocols for pediatric intra- and extra-cranial solid tumors. HCT can be curative, but is associated with significant toxicity.
  
  
  METHODS
  Between January 2001 and June 2009, 92 solid tumor patients (age 6 months to 27 years) underwent 94 autologous apheresis procedures at Children's National Medical Center. Out of that group, 71 patients, who underwent 162 autologous HCT, were analyzed for transplant outcomes. Multiple variable modeling was used to identify independent variables related to transplant toxicity outcome measures, such as bacteremia, intensive care admission, and death. Other outcome measures (time to pre-apheresis peripheral blood CD34+ count, product yield, and time to engraftment) were also analyzed. Independent variables included patient-specific variables (age, weight, tumor type, chemotherapy administered, and primary vs. relapsed disease) and harvest or transplant-related variables (total white blood cell and CD34+ cell counts prior to transplant, and quantity of total nucleated cells and CD34+ cells infused during transplant).
  
  
  RESULTS
  Transplant toxicity was significantly greater in younger patients (P = 0.001) and in neuroblastoma patients (P = 0.003). The time to neutrophil engraftment, controlling for weight, age, and chemotherapy, was positively related to absolute CD34+ cells/kg infused (P = 0.01). The time to CD34+ recovery pre-apheresis was affected by patient diagnosis (P = 0.05).
  
  
  CONCLUSIONS
  Younger patients had increased transplant toxicity, with infants <1 year of age at highest risk for fever, bacteremia, admission to intensive care, and death. Infants would likely benefit from hospitalization after autologous HCT until neutrophil recovery.
authors.affiliation: Pediatric Residency Program, Children's National Medical Center, Washington, District of Columbia, USA. ldubrov@gmail.com
authors.forename: Leonid
authors.initials: L
authors.lastname: Dubrovsky
authors.forename: Robert J
authors.initials: RJ
authors.lastname: McCarter
authors.forename: Terry J
authors.initials: TJ
authors.lastname: Fry
authors.forename: Edward
authors.initials: E
authors.lastname: Wong
authors.forename: Yao
authors.initials: Y
authors.lastname: Cheng
authors.forename: Evelio D
authors.initials: ED
authors.lastname: Perez-Albuerne
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D018952:Antigens, CD34 / Q000378:metabolism; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D016470:Bacteremia / Q000209:etiology; D001781:Blood Component Removal; D001932:Brain Neoplasms / Q000150:complications / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D009447:Neuroblastoma / Q000150:complications / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation / Q000009:adverse effects*; D011183:Postoperative Complications; D011379:Prognosis; D014182:Transplantation, Autologous; D055815:Young Adult
chemical_list: D018952:Antigens, CD34