Tomotherapy-based IMRT after limb-preserving surgery for extremity soft-tissue sarcomas: Planning, verification, and treatment times.

Abstract

e20514 Background: Radiotherapy improves local control after limb-sparing surgery for soft tissue sarcomas (STS). IMRT can optimize treatment dose conformity compared to standard conformal therapy. At the Northern Centre for Cancer Care we prescribe 60Gy. Until 2009 this was delivered using conventional Linac-based 3D conformal RT. Since installation of a tomotherapy unit, because of the potential long- term clinical advantages, selected sarcoma patients have been treated with postoperative IMRT. Tomotherapy necessitates longer planning, verification, and treatment times. These have been analysed to assess impact on resources. Methods: Six such patients have now been treated with IMRT. Tomotherapy planning requires more volume definition of organs at risk and “help structures” and processing for dose optimization. Times have been recorded within the implementation phase. Conventional Linac verification uses portal imaging daily for three days. Shifts are made to exclude systematic error, if tolerance is e...