Identifying Iron Overload in Pediatric Oncology Patients

Background. Intensive therapy for childhood cancer is possible in large part due to improvements in supportive care that are currently available. Blood product transfusions, including red blood cell transfusions, are supportive care measures which are important in the tolerability of this therapy, and are frequently used in the majority of patients receiving therapy for childhood cancer. Although it is well recognized that frequent red blood cell transfusions in pediatric hematological disorders, such as sickle cell disease and thalassemia major, lead to iron overload and its complications (ie, organ dysfunction), pediatric oncology patients receiving numerous red blood cell transfusions are not routinely screened or evaluated for risk of iron overload or its consequences. This study was done to identify pediatric oncology patients with iron overload in a general pediatric hematology/oncology clinic.

Methods. A retrospective blood bank records review was performed of pediatric hematology/oncology patients treated in our clinic in the last 10 years (2003-2013) to identify those patients receiving >10 packed red blood cell (PRBC) transfusions. These patients’ medical records were reviewed to determine which patients had been assessed for iron overload with a serum ferritin level. If a serum ferritin was obtained and the result was >1000 ug/L, records were reviewed to determine if patients received therapy for iron overload.

Results. For the time period 2003-2013, blood bank records were screened on 144 patients. Fifty patients (34.7%) were identified as receiving >10 PRBC transfusions. Of these patients, 22 (44%; M/F = 12/10; age range = 2-23 y/o) were patients who had received therapy or were on active therapy for childhood cancer; 14 with leukemia (5 AML, 9 ALL), 8 with solid tumors (5 sarcomas, 1 hepatoblastoma, 1 lymphoma). Of these 22 patients, 6 (27%) patients had a serum ferritin level that was obtained and the remaining 16 (73%) had not. All the patients (100%) with a serum ferritin result had a serum ferritin level >1000 ug/L (range 1048-22021). Only one patient (off-therapy sarcoma patient, serum ferritin =1788 ug/L) was on therapy for iron overload (Exjade and phlebotomy).

Conclusions. Pediatric oncology patients receiving numerous PRBC transfusions are at risk for iron overload. Routine risk screening and assessment for iron overload should be accomplished in all pediatric oncology patients as part of their off therapy follow-up management. For those identified as having iron overload, appropriate therapy should be considered as indicated.