Prognostic impact of iron parameters in patients undergoing allo-SCT

Iron overload contributes to increased transplant-related mortality, and serum ferritin is typically used to detect iron overload. Other iron parameters have received limited attention. We studied serum ferritin, transferrin, transferrin saturation, iron, soluble transferrin receptor (sTfR) and C-reactive protein (CRP) levels in 230 consecutive patients undergoing myeloablative allo-SCT. All iron parameters were significantly associated with survival. When analyzed individually, both sTfR and transferrin saturation were superior in prognostic power to ferritin (areas under the curve in receiver operating characteristic analysis: 0.670, 0.715, and 0.657, respectively). A combination of ferritin and transferrin saturation had the highest prognostic power: Patients with ferritin below the 30th percentile (<802 ng/mL) showed excellent survival (70±6% at 5 years), while transferrin saturation above the 80th percentile (≥69%) pointed to a high risk of transplant failure (5-year survival 5±5%). The remaining patients showed an intermediate outcome (5-year survival 52±5%). The prognostic impact of iron parameters was independent of other factors such as stage, conditioning regimen and CRP level, and operated similarly across diseases. Iron overload strongly influenced the outcome of allo-SCT. Low pre-transplant ferritin levels indicate a population at low risk, high transferrin saturations and a subgroup of patients with very poor outcome.