The effect of version update in radiotherapy treatment planning system on early-stage glottic laryngeal cancer plans

Abstract

Objectives: The study focus on to compare different versions of eclipse anisotropic analytical algorithm (AAA), AAA 10.0.28 and AAA 13.7.20, on the treatment plans designed with intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques for early-stage glottic laryngeal cancer patients through the dose-volume histograms (DVHs).

Patients and methods: Computerized tomography (CT) images of 10 cases’ were taken and transferred to the Eclipse treatment planning system (TPS). Double VMAT and 7-field IMRT plans were designed and calculated with two versions of Eclipse AAA, 4 calculated plans for each patient. Values obtained from DVH, for the planning target volume (PTV) homogeneity index (HI) and conformity index (CI), the dose received by 2% of the volume (D2%), D95%, and D98% values; for carotid artery right and carotid artery left the mean dose (Dmean), the volume receiving a 35Gy dose (V35Gy) and V50Gy, and for the spinal cord the maximum dose (Dmax) were recorded. Statistical analysis was performed with the non-parametric Wilcoxon sample test in the SPSS 17.0 program, and the significance was determined as p<0.05.

Results: For PTV, HI and CI values, the difference between the versions for VMAT and IMRT plans was not significant. While D2%, made a significant difference between the versions but only for the VMAT plans. Moreover, a significant difference was found between the versions of the IMRT plans in D95% and D98%. In the analysis of the right carotid artery, there was a significant difference between the versions of the IMRT plans for Dmean and the VMAT plans for V35Gy. In the left carotid artery analysis, there was a significant difference between the versions for Dmean and V35Gy for the IMRT plans. For Dmax values of the spinal cord, a significant difference was observed between versions for only IMRT treatment plans.

Conclusion: This study has proven that the use of the most up-to-date version of technology provides a more realistic dose distribution, especially in head and neck cancer patients in terms of high precision calculation of dose transition between tissues of different densities and maximum doses. As well as considerable to determining the patient's normal tissues and target volume very clearly and designing an accurate plan for radiotherapy.

Cite this article as: Çini N, Ceylaner Bıçakçı B. The effect of version update in radiotherapy treatment planning system on early-stage glottic laryngeal cancer plans. D J Med Sci 2024;10(1):11-17. doi: 10.5606/fng.btd.2024.141.

The study protocol was approved by the Kartal Dr. Lütfi Kırdar City Hospital Clinical Research Ethics Committee (date: 25.01.2023, no: 2022/514/242/3). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Since the study was designed retrospectively, no written informed consent form was obtained from patients.

Data Sharing Statement:
The data that support the findings of this study are available from the corresponding author upon reasonable request.

All authors contributed equally to the article.

The authors declared no conflicts of interest with respect to the authorship and/ or publication of this article.

The authors received no financial support for the research and/or authorship of this article.