• Christoph Baum, Mattias Birkner, Markus Alber, Frank Paulsen, and Fridtjof Nüsslin.
• Sektion für Biomedizinische Physik, Universitätsklinik für Radioonkologie, Universität Tübingen, Deutschland. christoph.baum@gmx.de
• Radiother Oncol. 2005 Jul 1; 76 (1): 35-42.

PurposeTo evaluate the consequences of a planning volume definition based on multiple CTs and the application of off-line setup error correction for the treatment of prostate cancer with intensity-modulated radiotherapy (IMRT). Further, to compare various setup correction protocols (SCP) by their influence on the average dose distributions.Materials And MethodsA planning target volume (PTV) consisting of the bounding volume of prostate contours of five CTs (CTV_hull) plus an additional margin of 5mm and a virtual Rectum_hull volume (the solid bounding volume of the five corresponding rectum contours) are used for treatment planning. Simulations of treatment courses with the non-parametric bootstrap method allow to estimate the distribution of the expected equivalent uniform dose (EUD). The impact of off-line setup error correction protocols is evaluated based on estimated EUD distributions.ResultsOff-line SCP allow to achieve the intended prostate and rectum EUD and a reliable coverage of the CTV despite the reduced margins. The EUD of the virtual hull volumes is a good estimate for the EUD of prostate and rectal wall.ConclusionTreatment planning based on Rectum_hull and CTV_hull plus setup margin as PTV in combination with SCP results in a robust and safe IMRT planning concept.

13 keywords...

hide…