S-Space College of Medicine/School of Medicine (의과대학/대학원) Radiation Oncology (방사선종양학전공) Journal Papers (저널논문_방사선종양학전공)
Effect of dose rate on pulmonary toxicity in patients with hematolymphoid malignancies undergoing total body irradiation
- Kim, Dong-Yun; Kim, Il Han; Yoon, Sung-Soo; Kang, Hyoung Jin; Shin, Hee Young; Kang, Hyun-Cheol
- Issue Date
- BioMed Central
- Radiation Oncology, 13(1):180
This study evaluated the effect of radiation dose rate in patients with hematolymphoid malignancies undergoing myeloablative conditioning with total body irradiation (TBI), for hematopoietic stem cell transplantation.
The incidence of pulmonary toxicity (PT) and treatment efficacy were compared between the conventional (≥ 6 cGy/min) and reduced dose rate (< 6 cGy/min). Seventy-seven patients receiving once-daily TBI between 2000 and 2016 were reviewed. We compared the cumulative rate of PT, overall survival (OS), relapse, and transplantation-related mortality (TRM) between conventional (n = 54) and reduced (n = 23) groups. Factors associated with PT were assessed in the presence of competing risks.
The median follow-up time was 40.7 months, and PT occurred in 50 patients (64.9%). On multivariate analyses, the groups classified by the dose rate (P = 0.010), total dose (P = 0.025), and conditioning regimen (P = 0.029) were significant factors for the development of PT. OS was significantly reduced when PT occurred (P < 0.001). However, the OS, relapse, and TRM were not different between the two groups.
In summary, about two-thirds of the patients undergoing daily TBI experienced PT, which affected OS. Therefore, reducing the dose rate (less than 6 cGy/min) of TBI can decrease the risk of PT, without compromising the treatment efficacy.