Fully automated volumetric modulated arc therapy planning for locally advanced rectal cancer: feasibility and efficiency.

Background: Volumetric modulated arc therapy (VMAT) for locally advanced rectal cancer (LARC) has emerged as a promising technique, but the planning process can be time-consuming and dependent on planner expertise. We aimed to develop a fully automated VMAT planning program for LARC and evaluate its feasibility and efficiency.

Methods: A total of 26 LARC patients who received VMAT treatment and the computed tomography (CT) scans were included in this study.

Plan Quality Comparison Between Hippocampus-Sparing Whole-Brain Radiotherapy Treated With Halcyon and Tomotherapy Intensity-Modulated Radiotherapy.

: Hippocampus-sparing whole-brain radiotherapy using Halcyon, an instrument dedicated to volumetric modulated arc therapy, has not been studied till date; hence, we aimed to examine whether it can meet the RTOG0933 criteria. Based on this, we compared Halcyon to Tomotherapy, which also uses an O-ring-type linear accelerator. This exploratory, experimental, and retrospective study used 5 sets of computed tomography images in the head area to investigate the planning target volume, hippocampal doses, and irradiation time.

[A Preliminary Study of Optimal Imaging Acquisition Parameters for Fiducial Markers in Liver Stereotactic Body Radiotherapy].

In liver stereotactic body radiotherapy (SBRT) using fiducial markers, the accuracy of automatic image recognition of fiducial markers is important, and the imaging dose cannot be neglected in image-guided radiotherapy. Optimal imaging parameters of fiducial markers were investigated for automatic image recognition and imaging dose. We investigated automatic recognition with fiducial markers of different shapes and sizes.

Frequency and predictors of detecting early locoregional recurrence/disease progression of oral squamous cell carcinoma with high-risk factors on imaging tests before postoperative adjuvant radiotherapy.

Background: To clarify the frequency and predictors of detecting early locoregional recurrence/disease progression (LR/DP) during the interval between surgery and postoperative adjuvant radiotherapy with/without chemotherapy in patients with oral squamous cell carcinoma.

Methods: Data on 65 patients who had undergone the initial radical surgery for previously untreated oral squamous cell carcinoma which were scheduled to receive adjuvant radiotherapy with/without chemotherapy were reviewed.

Results: Of the 65 patients, 63 (97%) were margin-positive/close and/or extracapsular extension-positive (hereinafter, high-risk factors).