Iron overload: predictor of adverse outcome in hematopoietic stem cell transplantation.

INTRODUCTION: Iron overload is an important problem in candidates for and survivors of hematopoietic stem cell transplantation (HSCT), and affects long-term outcome and survival. The objective of the present study was to determine the effect of iron overload on early toxic or infectious complications and survival. PATIENTS AND METHODS: We retrospectively reviewed the medical records for 250 adult patients (162 men and 88 women; median [range] age, 34 [16-71] years who underwent HSCT between September 2003 and August 2008. The HSCT grafts were autologous in 102 patients, and allogeneic in 148.
RESULTS: Follow-up was 315 (1-1809) days. Mean (SD) pre-HSCT serum ferritin concentration was 1402.6 (5016.2) ng/mL in the entire group, 647.6 (1204.3 ng/mL in autologous recipients, and 1410.6 (2410.4) ng/mL in allogeneic recipients. Twenty-eight autologous graft recipients (27.4%) and 102 allogeneic recipients (68.9%) demonstrated serum ferritin concentrations of 500 ng/mL or greater, and were classified as the high-ferritin group. High ferritin concentrations were significantly associated with toxic or infectious complications including mucositis, fungal infections, pneumonia, and sinusoidal obstruction syndrome in the early post-HSCT setting. A significant effect of pre-HSCT ferritin concentration on overall survival and transplant-related mortality was observed. The effect of pre-HSCT ferritin on survival was independent of the comorbidity index at Cox regression analysis. In the entire study population, the probability of survival was significantly lower when ferritin concentration was greater than 500 ng/mL.
CONCLUSION: Transplant-related mortality has decreased substantially with the development of supportive treatments. Pretransplantation risk assessment and risk-adapted strategies such as decreasing iron overload might further improve transplant-related complications.