Quality Assurance of Volumes Definition for Three-Dimensional Treatment Planning

The definition and contouring of targets constitute an important step in the process of treatment planning in modern conformal radiotherapy. It is a step usually done by the radiation oncologist and studies have shown that there is a significant element of uncertainty and inter-observer variations associated with it. This CRP will address this important question and will investigate variability and inconsistencies in contouring target volumes in computerized radiotherapy three dimensional (3D) treatment planning and develop a methodology to minimize these. A specific software tool for delineation will be selected and made available to a number of radiotherapy departments in Member States that are transitioning to the implementation of 3D conformal radiotherapy. Radiation oncologists in these departments will be asked to use the tool to delineate target volumes in cases of common cancers such as lung, breast, prostate, head-and-neck or rectal cancer, and submit them back to the Project Officer. A panel of experts from the IAEA and external consultants will study these cases and make an assessment of accuracy and uncertainties in the delineations. The research group will attempt to systematize the variabilities and compare them to published delineation guidelines. The objectives of the CRP are to: (1) validate the specific contouring software as a teaching tool; (2) assess the accuracy and uncertainties associated with its use in common cancers, and (3) train radiation oncologists in the participating centres on target volume delineation in common cancers for 3D conformal radiotherapy. The plan is to implement this CRP in cross-cutting collaboration with the European Society for Radiotherapy and Oncology (ESTRO).