[Physical aspects of standardization and optimization in radiotherapy].

Establishment of a quality assurance program of radiotherapy is required for the standardization and optimization of radiotherapy. Items to include in the quality assurance program are discussed briefly such as: evaluation of radiation dose, test of performance characteristics of radiotherapy equipments, system to prevent mistakes in delivery of radiotherapy, dose specification, method of statistical procedure and analysis of treatment results of patients, members of the radiation treatment planning team.