A Multicentre Timing Study of Intensity-modulated Radiotherapy Planning and Delivery

Abstract 

Aims

The aim of the study was to measure how long the intensity-modulated radiotherapy (IMRT) process takes, both for planning and delivery, using several IMRT techniques and departments.

Materials and methods

Timings were measured at three radiotherapy centres for each step of the process of outlining, planning and delivering IMRT for head and neck cancers. Times were measured for a total of 63 patients; 27 with helical tomotherapy, 37 with dynamic sliding window (26 in one centre, 11 in another) and nine with step-and-shoot.

Results

The mean time to outline a patient was 108min, to produce and check the plan 7.9h, to carry out and analyse patient-specific quality assurance 1.9h. The mean treatment time (including on-treatment verification imaging where carried out), measured gate to gate, was 28min 10s for first fractions and 20min 20s for subsequent fractions.

Conclusion

An analysis of subgroups showed some differences in times between techniques, and some differences between departments with the same techniques. For all four techniques, the median time from the end of outlining to the start of treatment was under 3 weeks.

Key words: IMRT, resources, timing