SU-E-J-195: Dosimetric Consequences of Metal Prosthesis in Prostate 3D CRT by Using Monte Carlo Dose Calculation Method

Medical Physics
Y ChenF Verhaegen

Abstract

To investigate dosimetric consequences of patient metal prosthesis in prostate radiotherapy, considering the body heterogeneity, metal artifacts, prostate daily displacements and target delineation. Three prostate patients with metal prosthesis were simulated with CT images and 3D ultrasound images. Conformal RT treatment plans were generated based on target volumes delineated on CT images without artifact correction (PTVa). The patients' treatments were aided with an ultrasound (US) localization system for daily PTV setup correction. We retrospectively reevaluated the delineation of PTVs by 1) using simulation CT images artifact-corrected by using an algorithm developed by M. Bazalova et al (2007) (PTVc) and 2) using the 3D ultrasound simulation images as guide (PTVus). Daily setup corrections to the PTVs were incorporated to calculate composite delivered dose by using XVMC simulation on the patient phantom derived from the artifact-corrected CT images. DVHs and dose distributions for different PTVs were then compared with the reference treatment plans (XVMC-calculated on the artifact-degraded CT images). The PTVa volume was the largest, about 1.3% larger than artifact-corrected PTVc and 5.2% larger than PTVus. Adapting artifa...Continue Reading

Related Concepts

Related Feeds

Bladder Carcinoma In Situ

Bladder Carcinoma In Situ is a superficial bladder cancer that occurs on the surface layer of the bladder. Discover the latest research on this precancerous condition in this feed.