Accuracy requirements and uncertainties in radiotherapy

At the American Association of Physicists in Medicine (AAPM) Annual Meeting in 2013, a session called 'accuracy required for radiotherapy and uncertainty to be considered' was established. This paper presents the IAEA report based on the contents of this session. The report consists of the following items: (1) introduction, (2) process of radiotherapy, (3) definition of terminology, (4) when thinking required accuracy: from the viewpoint of radiation biology, (5) when thinking required accuracy: from the viewpoint of clinical aspect, (6) accuracy that can actually be reached, (7) management of uncertainty, and (8) recommendations for accuracy and uncertainty. This paper briefly explained the contents of each item. It quantitatively discussed the accuracy that can actually be reached, from the aspects of dose calibration, measurement equipment used in the facility and dose calculation, image acquisition device, therapy equipment, and so on. It discussed the uncertainty management from the aspects of cost benefits, clinical tests, determination of uncertainty in facilities, representation of uncertainty, prevention and reduction of incidents / near misses, and so on. Radiotherapy is a very complex process involving several complex technologies. Since one item is insufficient to describe the accuracy to fit all radiation treatments, the IAEA report lists general recommendations No.1-9 that can be applied to all situations. (A.O.)