Statistical breathing curve sampling to quantify interplay effects of moving lung tumors in a 4D Monte Carlo dose calculation framework.

Purpose: The interplay between respiratory tumor motion and dose application by intensity modulated radiotherapy (IMRT) techniques can potentially lead to undesirable and non-intuitive deviations from the planned dose distribution. We developed a 4D Monte Carlo (MC) dose recalculation framework featuring statistical breathing curve sampling, to precisely simulate the dose distribution for moving target volumes aiming at a comprehensive assessment of interplay effects.

Methods: We implemented a dose accumulation tool that enables dose recalculations of arbitrary breathing curves including the actual breathing curve of the patient.

Comparison of liver exposure in CT-guided high-dose rate (HDR) interstitial brachytherapy versus SBRT in hepatocellular carcinoma.

Background: In unresectable hepatocellular carcinoma several local ablative treatments are available. Among others, radiation based treatments such as stereotactic body radiotherapy (SBRT) and high-dose rate interstitial brachytherapy (HDR BT) have shown good local control rates.

Methods: We conducted a dose comparison between actually performed HDR BT versus virtually planned SBRT to evaluate the respective clinically relevant radiation exposure to uninvolved liver tissue.

Radiotherapy in oncological emergencies: fast-track treatment planning.

Background And Purpose: To report on our clinical experience with a newly implemented workflow for radiotherapy (RT) emergency treatments, which allows for a fast treatment application outside the regular working-hours, and its clinical applicability.

Methods: Treatment planning of 18 emergency RT patients was carried out using diagnostic computed tomography (CT) without a dedicated RT simulation CT. The cone-beam CT (CBCT) deviations of the first RT treatment were analyzed regarding setup accuracy.

Novel rotatable tabletop for total-body irradiation using a linac-based VMAT technique.

Background: Volumetric Modulated Arc Therapy (VMAT) techniques have recently been implemented in clinical practice for total-body irradiation (TBI). To date, most techniques still use special couches, translational tables, or other self-made immobilization devices for dose delivery. Aim of the present study was to report the first results of a newly developed rotatable tabletop designed for VMAT-TBI.