Influence of comorbidities on transplant outcomes in patients aged 50 years or more after myeloablative conditioning incorporating fludarabine, BU and ATG

Non-myeloablative (MA) and reduced intensity allo-SCT regimens are offered to older patients and/or those with comorbidities because the morbidity and mortality attributable to fully MA conditioning is thought to be unacceptably high. A total of 207 patients aged 50–66 years were treated between 1999 and 2008 with SCT after MA conditioning with fludarabine 50 mg/m2 daily × 5 and i.v. BU 3.2 mg/kg daily × 4.90 (43%) had additional TBI 200 cGy × 2. GVHD prophylaxis was CsA, MTX and thymoglobulin (4.5 mg/kg total dose). As defined by the hematopoietic cell transplantation co-morbidity index (HCT-CI) scoring system 117 (57%) pts scored 0 and 90 (43%) ⩾1. At 5 years OS was 39 vs 54% (P=0.008), disease-free survival 38 vs 49% (P=0.03), TRM 39 vs 19% (P=0.003) and relapse 36 vs 39% (P=ns) in those with scores of 0 and ⩾1, respectively. Multivariate analysis confirmed the influence of HCT-CI scores on TRM (subhazard ratios=2.29; 95% confidence interval=1.29–4.08; P=0.005). We conclude that comorbidities as assessed by the HCT-CI do influence TRM with this regimen but that age alone should not be an indication to prefer a less intense protocol.