title: Comorbidity and disease status based risk stratification of outcomes among patients with acute myeloid leukemia or myelodysplasia receiving allogeneic hematopoietic cell transplantation.
abstract: OBJECTIVE
  Retrospective studies have shown similar survival among patients with acute myeloid leukemia (AML) and myelodysplasia (MDS) after nonmyeloablative compared with myeloablative conditioning. Refined risk stratification is required to design prospective trials.
  
  
  METHODS
  We stratified outcomes among patients with AML (n = 391) or MDS (n = 186) who received either nonmyeloablative (n = 125) or myeloablative (n = 452) allogeneic hematopoietic cell transplantation (HCT) based on comorbidities, as assessed by a HCT-specific comorbidity index (HCT-CI), as well as disease status. Patients receiving nonmyeloablative conditioning were older, more frequently pretreated, more often received unrelated grafts, and more often had HCT-CI scores of 3 compared with patients who received myeloablative conditioning.
  
  
  RESULTS
  Patients with HCT-CI scores of 0 to 2 and either low or high disease risks had probabilities of overall survival at 2 years of 70% and 57% after nonmyeloablative conditioning compared with 78% and 50% after myeloablative conditioning, respectively. Patients with HCT-CI scores of 3 and either low or high disease risks had probabilities of overall survival of 41% and 29% with nonmyeloablative conditioning compared with 45% and 24% with myeloablative regimens, respectively. After adjusting for pretransplantation differences, stratified outcomes were not significantly different among patients receiving nonmyeloablative compared with myeloablative conditioning, with the exception of lessened nonrelapse mortality (hazard ratio, 0.50; P = .05) in the highest risk group.
  
  
  CONCLUSIONS
  Patients with low comorbidity scores could be candidates for prospective randomized trials comparing nonmyeloablative and myeloablative conditioning regardless of disease status. Additional data are required for patients with low-risk diseases and high comorbidity scores. Novel antitumor agents combined with nonmyeloablative HCT should be explored among patients with high comorbidity scores and advanced disease.
authors.affiliation: Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA. msorror@fhcrc.org
authors.forename: Mohamed L
authors.initials: ML
authors.lastname: Sorror
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Sandmaier
authors.forename: Barry E
authors.initials: BE
authors.lastname: Storer
authors.forename: Michael B
authors.initials: MB
authors.lastname: Maris
authors.forename: Frédéric
authors.initials: F
authors.lastname: Baron
authors.forename: David G
authors.initials: DG
authors.lastname: Maloney
authors.forename: Bart L
authors.initials: BL
authors.lastname: Scott
authors.forename: H Joachim
authors.initials: HJ
authors.lastname: Deeg
authors.forename: Frederick R
authors.initials: FR
authors.lastname: Appelbaum
authors.forename: Rainer
authors.initials: R
authors.lastname: Storb
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015897:Comorbidity; D018572:Disease-Free Survival; D005260:Female; D006680:HLA Antigens / Q000378:metabolism; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000150:complications* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009436:Neural Tube Defects / Q000150:complications* / Q000628:therapy*; D014184:Transplantation, Homologous; D016896:Treatment Outcome
chemical_list: D006680:HLA Antigens