National survey on total-body irradiation prior to reduced-intensity stem cell transplantation in Japan: The Japanese Radiation Oncology Study Group

Abstract

Reduced-intensity stem cell transplantation (RIST) minimizes the adverse effects of traditional hematopoietic stem cell transplantation, and low-dose total-body irradiation (TBI) is administered over a short period prior to RIST (TBI–RIST). Different institutes adopt different approaches for the administration of TBI–RIST, and since no study had previously investigated this issue, a survey of the TBI schedules in Japan was conducted. In October 2015, the Japanese Radiation Oncology Study Group initiated a national survey of TBI–RIST procedures conducted between 2010 and 2014. Of 186 institutions performing TBI, 90 (48%) responded to the survey, 78 of which performed TBI–RIST. Of 2488 patients who underwent TBI for malignant disease at these institutions, 1412 (56.8%) patients were treated for leukemia, 477 (19.2%) for malignant lymphoma, 453 (18.2) for myelodysplastic syndrome, 44 (1.8%) for multiple myeloma, and 102 (4.1%) for other malignant diseases. Further, 206 (52.0%) of 396 patients (a high proportion of patients) who underwent TBI for benign disease had aplastic anemia. The TBI–RIST equipment and treatment methods were similar to those used for myeloablative regimens. Routinely shielded organs included the lungs (43.6%), eyes (50.0%) and kidneys (10.2%). The ovaries (14.1%), thyroid (6.4%) and testicles (16.7%) were also frequently shielded, possibly reflecting an emphasis on shielding reproductive organs in children. TBI–RIST was performed more frequently than myeloablative conditioning in patients with benign disease. Genital and thyroid shielding were applied more frequently in patients treated with TBI–RIST than in patients treated with myeloablative conditioning. In conclusion, this study indicates the status of TBI–RIST in Japan and can assist future efforts to standardize TBI–RIST treatment methods and to design a future multicenter collaborative research study.

First Experience of Standard Linac, Rapid Arc and Dose-drop Scheme Based Total Body Irradiation

“…5,9.9% ± 3.7, 15.1% ± 4.2 and 22.6% ± 3.1 higher maximum lung doses and 3.6% ± 1.3, 11.9% ± 3.2, 20.4% ± 3.6 and 22.0% ± 3.8 higher point doses were obtained respectively. Our studies showed dose-drop positioning related dose deviation control technology can reduce dose distribution error 19.…”

“…During the process of each fraction radiotherapy, total eight interest point sites dose monitoring were done, then all the isocentric accumulative doses were added and analyzed, the results showed an overall deviation of -3.9%±5.51%. Discussion 5,6 TBI is mainly used for leukemia, followed by malignant lymphoma, myelodysplastic syndrome, multiple myeloma and other malignant diseases. It is also used for benign diseases such as aplastic anemia.…”

Commissioning of total body irradiation using plastic bead bags

“…The Japanese Radiation Oncology Study Group (JROSG) recently reported the national survey on TBI prior to RIST [ 6 ]. They reported that 57.7% of institutions used the prescribed dose of 4 Gy/2 fractions/1–2 days.…”

“…For myeloablative conditioning, a prescribed dose ranging from 12 to 13.2 Gy has been commonly used to attenuate the immunity of the recipient and to destroy cancer cells [ 4 ]. For reduced-intensity stem cell transplantation (RIST) combined with TBI, a prescribed dose ranging from 2 to 6 Gy has been used [ 5 , 6 ]. To irradiate the whole patient body, various techniques, such as long source-to-surface distance (SSD), moving bed [ 7 , 8 ] and helical tomotherapy [ 9 , 10 ], have been used.…”

Low-Dose Radiation to COVID-19 Patients to Ease the Disease Course and Reduce the Need of Intensive Care

“…10), which allows for monitoring and controlling the potential risk associated with the frequent exposure of the healthcare staff involved in administering LDR to COVID-19 patients.by on November 4, 2020. For personal use only.…”