It May Be Clinically Acceptable to Delay Growth Factor Treatment in Children Post-Chemotherapy

Study Aims to Help Clarify Best-Practice Timing in Pediatrics

Treating children with growth factors as late as five days after they receive a bone marrow or blood stem cell transplant may result in substantial cost savings and still be as clinically beneficial as treating patients one day after transplantation. These findings are from a Nationwide Children’s Hospital study appearing in Pediatric Blood & Cancer, the first study to examine whether delayed administration in pediatrics affects engraftment time. 

Autologous bone marrow transplant (ABMT) and peripheral blood stem cell transplantation (APBSCT) are procedures that restore stem cells that have been destroyed by high doses of chemotherapy or radiation therapy. Growth factors, such as G-CSF, are commonly used before transplantation to stimulate stem cells and after transplantation to decrease the amount of time that a patient’s white blood cell count is low. 

Current American Society of Clinical Oncology best-practice guidelines recommend initiating G-CSF one-to-five days after high-dose chemotherapy and blood stem cell transplantation. Studies in adult patients suggest that favoring the far end of this spectrum is acceptable practice.

“The optimal timing for initiation of G-CSF is not well known,” said Amanda M. Termuhlen, MD, associate chief of Pediatric Hematology/Oncology/Blood and Marrow Transplantation at Nationwide Children’s Hospital and one of the study authors. “A number of predominately adult patient studies have been conducted to determine this timing, mostly suggesting that delayed initiation of G-CSF does not adversely affect the outcomes of transplantation.”  However, no pediatric-specific data exists.

Faculty from Nationwide Children’s and The Ohio State University analyzed the outcomes of 65 children who underwent APBSCT and high-dose chemotherapy at Nationwide Children’s for treatment of a hematological cancer or solid tumor during a 13-year period. They then compared the effect early administration (one day after transplant) and delayed administration (five days after transplant) of G-CSF had on “time to neutrophil engraftment,” the amount of time it takes for the donated cells to grow and make new blood cells.

Results were similar to those achieved in adult studies.  “It seems that administration of G-CSF one day post-transplantation may have very little benefit on time to neutrophil engraftment,” said Dr. Termuhlen. “Our study demonstrated that a five-day delay in G-CSF administration did not affect time to neutrophil engraftment and the number of blood stream infections was not different between the groups.” Delayed treatment also required less use of G-CSF, resulting in a $1,185 to $1,896 cost savings per patient.

Although this study is limited by its retrospective nature, Dr. Termuhlen says their findings confirm that there is no clinical benefit to starting G-CSF 24 hours post-transplant in children.

Pai V, Fernandez SA, Laudick M, Rosselet R, Termuhlen A. Delayed administration of filgrastim (G-CSF) following autologous peripheral blood stem cell transplantation (APBSCT) in pediatric patients does not change time to neutrophil engraftment and reduces use of G-CSF. Pediatr Blood Cancer. 2010 May;54(5):728-33.