In a nutshell
The study aimed to investigate optimized conformal (OC) total body irradiation (TBI) in pediatric patients with blood cancers who received further chemotherapy and allogeneic hematopoietic stem cell transplant (alloHSCT) with TCRαβ/CD19 depletion.
This study concluded that OC-TBI is a promising treatment method in these patients.
A conditioning regimen is the treatment used to prepare a patient for stem cell transplantation. Total body irradiation (TBI) in combination with chemotherapy is widely used as a conditioning regimen for pediatric and adult hematopoietic stem cell transplantation (HSCT). TBI kills any cancer cells left after chemotherapy and helps make room for new blood stem cells to grow. It can also help prevent the immune system from rejecting transplanted cells.
The combination of TBI and chemotherapy has shown better survival outcomes in patients with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) when compared to conditioning regimens with chemotherapy only.
Intensity-modulated radiation therapy (IMRT)-based methods (volumetric modulated arc therapy; VMAT and TomoTherapy) are current radiotherapy techniques that have shown promising outcomes. These treatments can be used for optimized conformal total body irradiation (OC-TBI).
One important side effect of alloHSCT is graft versus host disease (GVHD) in which the transplanted cells attack the patients. TCRαβ/CD19-depleted grafts are stem cells collected for HSCT in which some parts of the cells have been removed to reduce the risk of GVHD.
It is important to evaluate whether OC-TBI followed by chemotherapy and alloHSCT with TCRαβ/CD19-depleted grafts was safe and effective in pediatric patients with advanced blood cancers.
Methods & findings
This study involved 220 pediatric patients who received OC-TBI followed by chemotherapy and alloHSCT with TCRαβ/CD19 depletion. 151 patients received OC-TBI using TomoTherapy and 40 patients received OC-TBI using VMAT. 29 patients received OC-TBI with a supplemental simultaneous boost to the bone marrow. The average followed up period was 2.8 years.
At follow-up, 63% of patients were alive and 58% were alive without complications from the cancer.
The overall occurrence of mortality due to transplant over time was 10.7%. This was mostly caused by infections.
The bottom line
This study concluded that OC-TBI is a promising treatment prior to chemotherapy and alloHSCT for pediatric patients with blood cancers.
The fine print
This study included a small number of participants. There was no comparison group. Larger studies are needed to confirm these results.
Published By :
Frontiers in oncology
Jan 04, 2022