The transplant iron score as a predictor of stem cell transplant survival.
Recent studies have suggested that the presence of iron overload prior to stem cell transplantation is associated with decreased survival. Within these studies, the criteria used to define iron overload have varied considerably. Given the lack of consensus regarding the definition of iron overload in the transplant setting, we sought to methodically examine iron status among transplant patients. We studied 78 consecutive patients at risk for transfusion-related iron overload (diagnoses included AML, ALL, MDS, and aplastic anemia) who received either autologous or allogeneic stem cell transplant. Multiple measures of iron status were collected prior to transplantation and examined for their association with survival. Using this data, three potentially prognostic iron measures were identified and incorporated into a rational and unified scoring system. The resulting Transplant Iron Score assigns a point for each of the following variables: (1) greater than 25 red cell units transfused prior to transplantation; (2) serum ferritin > 1000 ng/ml; and (3) a semi-quantitative bone marrow iron stain of 6+. In our cohort, the score (range 0 to 3) was more closely associated with survival than any available single iron parameter. In multivariate analysis, we observed an independent effect of iron overload on transplant survival (p = 0.01) primarily attributable to an increase in early treatment-related deaths (p = 0.02) and lethal infections. In subgroup analysis, the predictive power of the iron score was most pronounced among allogeneic transplant patients, where a high score (> or = 2) was associated with a 50% absolute decrease in survival at one year. In summary, our results lend further credence to the notion that iron overload prior to transplant is detrimental and suggest iron overload may predispose to a higher rate of lethal infections.
Department of Internal Medicine, Section on Hematology and Oncology, Wake Forest University School of Medicine, Winston-Salem, NC, USA. jonstorey@live.com
Jonathan A
JA
Storey
Rebecca F
RF
Connor
Zachary T
ZT
Lewis
David
D
Hurd
Gregory
G
Pomper
Yi K
YK
Keung
Manisha
M
Grover
James
J
Lovato
Suzy V
SV
Torti
Frank M
FM
Torti
István
I
Molnár
D000328:Adult; D000741:Anemia, Aplastic / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D005260:Female; D006801:Humans; D007501:Iron / Q000032:analysis / Q000097:blood*; D019190:Iron Overload / Q000209:etiology / Q000401:mortality*; D007938:Leukemia / Q000097:blood / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009190:Myelodysplastic Syndromes / Q000097:blood / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D011379:Prognosis; D012107:Research Design; D033581:Stem Cell Transplantation / Q000009:adverse effects / Q000401:mortality*; D016019:Survival Analysis
D007501:Iron