lessons learnt from errors in radiotherapy centers

background: the purpose of this work is to discover and analyze errors and incidents in some radiotherapy centers, and to introduce methods that could reduce their occurrences, especially those which had happened due to the use of improper and inadequate equipment. this work is a first step toward clarifying the role of education in a risk-conscious culture, and changing the attitude of radiotherapy staff when they are working under encouraging conditions that remove barriers for reporting errors. materials and methods: for the present study clinical investigation, the data of 6000 patients were checked. they were treated at a few radiotherapy centers during one year. patients were treated by linear accelerator or cobalt machine, photon or electron beams. a purposely designed check list was used for error data collection. incidents were discovered by manual check at different steps of treatment. by highlighting frequency of occurrence, further investigation for preventing error repetition can be possible. eighty five incidents were reported by technologists, fifty four were reported by physicists, and twenty six events were pointed out by radiation oncologists. results: about fifty percent of total 165 detected events were classified as treatment field errors. geometrical misses in treatment field have the highest probability for both photon and electron beams. conclusion: incident prevention considering likelihood of individual event can be possible when using facilities like record-and-verification (r&v;) system and electronic-portal-image-device (epid), taking seriously qa, defining and implementing layers of defense in depth, and making an organized system for reporting and analyzing errors.