Anatomical changes and dosimetric analysis of the neck region based on FBCT for nasopharyngeal carcinoma patients during radiotherapy.

IF 16.4 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Accounts of Chemical Research Pub Date : 2024-01-01 DOI:10.3233/XST-230280

Aoqiang Chen, Xuemei Chen, Xiaobo Jiang, Yajuan Wang, Feng Chi, Dehuan Xie, Meijuan Zhou

{"title":"Anatomical changes and dosimetric analysis of the neck region based on FBCT for nasopharyngeal carcinoma patients during radiotherapy.","authors":"Aoqiang Chen, Xuemei Chen, Xiaobo Jiang, Yajuan Wang, Feng Chi, Dehuan Xie, Meijuan Zhou","doi":"10.3233/XST-230280","DOIUrl":null,"url":null,"abstract":"Background: The study aimed to investigate anatomical changes in the neck region and evaluate their impact on dose distribution in patients with nasopharyngeal carcinoma (NPC) undergoing intensity modulated radiation therapy (IMRT). Additionally, the study sought to determine the optimal time for replanning during the course of treatment.Methods: Twenty patients diagnosed with NPC underwent IMRT, with weekly pretreatment kV fan beam computed tomography (FBCT) scans in the treatment room. Metastasized lymph nodes in the neck region and organs at risk (OARs) were redelineation using the images from the FBCT scans. Subsequently, the original treatment plan (PLAN0) was replicated to each FBCT scan to generate new plans labeled as PLAN 1-6. The dose-volume histograms (DVH) of the new plans and the original plan were compared. One-way repeated measure ANOVA was utilized to establish threshold(s) at various time points. The presence of such threshold(s) would signify significant change(s), suggesting the need for replanning.Results: Progressive volume reductions were observed over time in the neck region, the gross target volume for metastatic lymph nodes (GTVnd), as well as the submandibular glands and parotids. Compared to PLAN0, the mean dose (Dmean) of GTVnd-L significantly increased in PLAN5, while the minimum dose covering 95% of the volume (D95%) of PGTVnd-L showed a significant decrease from PLAN3 to PLAN6. Similarly, the Dmean of GTVnd-R significantly increased from PLAN4 to PLAN6, whereas the D95% of PGTVnd-R exhibited a significant decrease during the same period. Furthermore, the dose of bilateral parotid glands, bilateral submandibular glands, brainstem and spinal cord was gradually increased in the middle and late period of treatment.Conclusion: Significant anatomical and dosimetric changes were noted in both the target volumes and OARs. Considering the thresholds identified, it is imperative to undertake replanning at approximately 20 fractions. This measure ensures the delivery of adequate doses to target volumes while mitigating the risk of overdosing on OARs.","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":" ","pages":"783-795"},"PeriodicalIF":16.4000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.3233/XST-230280","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

Background: The study aimed to investigate anatomical changes in the neck region and evaluate their impact on dose distribution in patients with nasopharyngeal carcinoma (NPC) undergoing intensity modulated radiation therapy (IMRT). Additionally, the study sought to determine the optimal time for replanning during the course of treatment.

Methods: Twenty patients diagnosed with NPC underwent IMRT, with weekly pretreatment kV fan beam computed tomography (FBCT) scans in the treatment room. Metastasized lymph nodes in the neck region and organs at risk (OARs) were redelineation using the images from the FBCT scans. Subsequently, the original treatment plan (PLAN0) was replicated to each FBCT scan to generate new plans labeled as PLAN 1-6. The dose-volume histograms (DVH) of the new plans and the original plan were compared. One-way repeated measure ANOVA was utilized to establish threshold(s) at various time points. The presence of such threshold(s) would signify significant change(s), suggesting the need for replanning.

Results: Progressive volume reductions were observed over time in the neck region, the gross target volume for metastatic lymph nodes (GTVnd), as well as the submandibular glands and parotids. Compared to PLAN0, the mean dose (Dmean) of GTVnd-L significantly increased in PLAN5, while the minimum dose covering 95% of the volume (D95%) of PGTVnd-L showed a significant decrease from PLAN3 to PLAN6. Similarly, the Dmean of GTVnd-R significantly increased from PLAN4 to PLAN6, whereas the D95% of PGTVnd-R exhibited a significant decrease during the same period. Furthermore, the dose of bilateral parotid glands, bilateral submandibular glands, brainstem and spinal cord was gradually increased in the middle and late period of treatment.

Conclusion: Significant anatomical and dosimetric changes were noted in both the target volumes and OARs. Considering the thresholds identified, it is imperative to undertake replanning at approximately 20 fractions. This measure ensures the delivery of adequate doses to target volumes while mitigating the risk of overdosing on OARs.

查看原文本刊更多论文

基于 FBCT 的鼻咽癌患者放疗期间颈部解剖学变化和剂量学分析。

研究背景该研究旨在调查接受调强放射治疗（IMRT）的鼻咽癌（NPC）患者颈部的解剖学变化及其对剂量分布的影响，并确定治疗过程中重新扫描的最佳时间：20名鼻咽癌患者接受了IMRT治疗，每周进行一次治疗前室内千伏扇形束计算机断层扫描（FBCT）。根据 FBCT 扫描结果对颈部转移淋巴结和危险器官 (OAR) 进行重新构图。原始治疗方案（PLAN0）被复制到每个 FBCT 扫描中，以创建相应的新方案（PLAN 1-6）。比较新计划和原始计划的剂量-体积直方图（DVH）。采用单因素重复测量方差分析来定义任意时间点的阈值。阈值的出现表明解剖结构发生了重大变化，应建议重新扫描：结果：随着时间的推移，观察到颈部区域、转移淋巴结总目标体积（GTVnd）、颌下腺和腮腺的体积逐渐缩小。与计划0相比，GTVnd-L的Dmean在计划5中显著增加，而PGTVnd-L的D95%从计划3到计划6显著减少。同样，GTVnd-R 的 Dmean 值从 PLAN4 到 PLAN6 显著增加，而 PGTVnd-R 的 D95% 值从 PLAN3 到 PLAN6 显著下降。此外，从计划0到计划6，投射到双侧腮腺、双侧颌下腺、脑干和脊髓的剂量逐渐增加：结论：在靶体积和 OAR 中观察到了显著的解剖和剂量变化。根据已确定的阈值，在大约 20 个分次时重新扫描对于确保足够的靶体积剂量和避免 OARs 剂量过大至关重要。这种方法在临床上是可行的，强烈推荐使用，尤其是对于没有自适应计划系统的中心。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Accounts of Chemical Research 化学-化学综合

CiteScore

31.40

自引率

1.10%

发文量

312

审稿时长

2 months

期刊介绍： Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance. Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.