Dosimetry effect of fluence smoothing in Monaco Treatment Planning System for short-course volumetric modulated arc therapy of preoperative rectal cancer
10.19745/j.1003-8868.2025086
- VernacularTitle:Monaco计划系统中通量平滑度对直肠癌术前短程容积旋转调强放疗剂量学的影响研究
- Author:
Yao XIAO
1
;
De-li ZHOU
1
;
Kun-pu SU
1
;
Lin-shan LI
1
;
Meng-yuan SI
1
;
Yan-hai LIU
1
;
Chuan CHEN
1
Author Information
1. 陆军特色医学中心肿瘤科,重庆 400012
- Publication Type:Journal Article
- Keywords:
Monaco Treatment Planning System;
fluence smoothing;
short-course radiotherapy;
rectal cancer;
preoperati-ve radiotherapy;
volumetric modulated arc therapy
- From:
Chinese Medical Equipment Journal
2025;46(5):48-53
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the dosimetric differences in preoperative short-course volumetric modulated arc therapy(VMAT)for rectal cancer using different fluence smoothing(FS)levels in the Monaco Treatment Planning System(Monaco TPS).Methods Twenty rectal cancer patients who received preoperative neoadjuvant short-course VMAT at some hospital from September 2021 to December 2022 were retrospectively selected.Four groups of radiotherapy plans were formulated using the Monaco TPS for each case,which were classified into an off group,a low group,a medium group and a high group based on the FS levels.Then the four groups were compared in terms of the dosimetric parameters,monitor unit and number of the segments in the planning target volume(PTV)and organ at risk(OAR).Statistical analysis was performed using SPSS 27.0 software.Results All the four groups had the doses to the target volume meeting clinical requirements,which had no significant differences in the doses to 5％(D5％)and 95％(D95％)to the target volume and the maximum dose(Dmax),minimum dose(Dmin),mean dose(Dmean)and conformity index(all P＞0.05).Statistical differences were found between the homogeneity indexes of the four groups(P＜0.05),with the medium group behaving the best.The number of the segments rose while the mornitor units decreased siginificantly with the increase of FS levels,with the differences being statistically significant(P＜0.05).There were no significant differences between the V25,V20,V15 and V10 of the small intestine,the V25 and V20 of the bladder and the V15 and V10 of the left and right femur(all P＞0.05).Conclusion In preoperative short-course VMAT for rectal cancer,clinical requirements can be met with different FS levels in the Monaco TPS,and medium-level FS results in optimal overall dose distribution in terms of treatment planning.[Chinese Medical Equipment Journal,2025,46(5):48-53]
