Preliminary study on the implementation of HT for segmented TMLI in adults
10.3969/j.issn.1672-8270.2025.09.005
- VernacularTitle:螺旋断层治疗用于成年人全骨髓全淋巴分段式照射的初步探究
- Author:
Haiyang WANG
1
;
Gaoxiang CHEN
1
;
Xiang HUANG
1
;
Ruigang GE
1
;
Shilei ZHANG
1
;
Changxin YAN
1
;
Chuanbin XIE
1
Author Information
1. 解放军总医院第一医学中心放射治疗科 北京 100853
- Publication Type:Journal Article
- Keywords:
Total marrow and lymphoid irradiation(TMLI);
Helical tomotherapy;
Segmented irradiation;
Acute leukemia;
Positional error
- From:
China Medical Equipment
2025;22(9):21-26
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the feasibility of segmented total marrow and lymphoid irradiation(TMLI)using Helical TomoTherapy(HT)in adults,and to analyze the impact of positional errors in the treatment on the actually received dose.Methods:Imaging data from four adult patients with acute myeloid leukemia were treated at the First Medical Center of the Chinese PLA General Hospital between November 2022 and December 2024 were retrospectively selected.The prescribed dose was 12 Gy in 3 fractions,and the heights range of patient was from 162 to 178 cm.The planning target volume(PTV)included the entire bone marrow and lymphatic drainage regions.The mid-femur was used as the dividing landmark,and the segmented location of head-in first(upper segmentation)and foot-in first(lower segmentation)were adopted to design plan for each segmentation.The upper segmentation used helical tomotherapy,and the lower segmentation used tomo direct therapy.The dosimetric parameters of planning target volume,and organ at risk(OAR)included eye lens,testicles and lungs were analyzed.The located computed tomography(CT)images of patients were used to simulate the changes of dosimetric parameters of each planning target region and OAR when the positions of patients moved 3,5,10 and 15 mm to outside of rack aperture.The changes of dose distribution of connection region of upper and lower segmentation were further analyzed.Results:The segmented irradiation technique can better achieve the cover(95%)of whole target region of TMLI under the condition of protecting normal organs.Under the condition with different position errors,the cover rate of the most of target region significant decreased.The largest dose of right lens increased 9.272%than primary under the 5 mm position error,and that of left and right lens increased respectively 40.199%and 67.898%under the 10 mm position error,and the max dose and mean dose of testicles increased respectively 5.847%and 5.240%under the 3mm position error.The mean dose of whole lung increased all under the error at different grades,which increased 3.021%under the 10mm position error.The non-uniformity of dose distribution of connection region increased after the position error was introduced,and the largest variation range reached to 4 Gy.Conclusion:The technique of segmented radiotherapy of Helical Tomotherapy has feasibility for TMLI of adult.But the error of the position of patients can reduce the cover of target region,and decrease the control rate for target region,and can lead to the occurrences of excessive doses on eye lens,testicles,lung and other OAR at the same time,which can increase the probability of occurring OAR injury.It should be high pay attention in treatment and implementation.
