Comprehensive Comparison of Progressive Optimization Algorithm Based Automatic Plan and Manually Planned Treatment...

Area of Science:

• Radiation Oncology
• Medical Physics
• Oncology

Background:

• Cervicothoracic esophageal cancer (CTEC) requires precise radiotherapy techniques.
• Traditional methods like intensity-modulated radiation therapy (IMRT) and manual VMAT have limitations in planning efficiency and plan quality.
• Advancements in automated planning are crucial for optimizing radiation delivery.

Purpose of the Study:

• To evaluate the feasibility and effectiveness of progressive optimization algorithm-based automatic volumetric modulated arc therapy (POA-VMAT) for CTEC treatment.
• To compare POA-VMAT with manual VMAT and step-shoot IMRT in terms of dosimetric results and normal tissue complication probability (NTCP).

Main Methods:

• Retrospective analysis of 60 CTEC patients treated between 2017-2019.
• Generation of manual 7-field IMRT (7f-IMRT), Single-arc-VMAT, Double-arc-VMAT, and POA-VMAT plans.
• Quantitative evaluation using dose-volume histograms, homogeneity index (HI), and conformity index (CI).

Main Results:

• POA-VMAT demonstrated superior target dose conformity compared to 7f-IMRT and comparable results to Double-Arc VMAT.
• POA-VMAT achieved a homogeneity index (HI) of 0.28 ± 0.03, comparable to other VMAT techniques.
• Significant differences in NTCP were observed among POA-VMAT, IMRT, and VMAT plans. POA-VMAT and Single-Arc VMAT reduced total monitor units (MU) by 42.1% and 48.3% respectively, compared to IMRT.

Conclusions:

• POA-VMAT is an efficient method for generating acceptable radiotherapy plans for CTEC.
• This automated technique offers superior plan quality compared to manual planning without increasing radiation dose to organs at risk (OARs).
• POA-VMAT presents a valuable option for optimizing CTEC treatment.