CLINICAL RESULTS OF QUANTITIZING DOSES BY MOSFET DOSIMETRY MEASUREMENTS IN PEDIATRIC BONE MARROW TRANSPLANT WITH TOTAL BODY IRRADIATION

Total body irradiation is an important part of the pre-HSCT preparation regimen. In treatments applied in combination with radiotherapy and chemotherapy, survival is long-term, especially in pediatric cases. So, increasing the quality of life of patients is as important as the success of the treatment. Today, the general approach is the application of the TBI with conventional radiotherapy devices.In the TBI applications, it is recommended to use in-vivo dosimeters to measure, quantify, control and monitor the dose homogeneity applied to the patient.In this study, we evaluated the importance of inter-fraction dose tracking for bilateral TBI irradiations, which is the most commonly used, simple and feasible method.Measurements were made with MOSFET for brain, neck, lung, umbilicus and pelvis regions in each fraction during the entire treatment, to prevent inter-fractional variations. The midline dose was calculated from the MOSFET skin doses and then interpreted. Dosage tracking within fractions allows the revision of the dosimetric errors that may occur between the fractions, and prevents the transfer of the possible error to the next fraction. Thus, it is aimed to minimize the possible side effects of the treatment and to reach the maximum targeted dose that will prevent recurrence and/or graft failure.