Dose evaluation method for adaptive radiotherapy plans based on script functions

Objective To investigate the dose evaluation method for adaptive radiotherapy plans based on script functions, so that the function of radiotherapy plan transfer in the Dynamic Planning module can be completed by all versions of Pinnacle treatment planning system (TPS). Methods The first step was to write and embed the scripts, and then the isocenter of irradiation was set up in the late-course image space. The scripts were executed to export and import the radiation field and set up the weight, so as to realize the transfer of radiotherapy plan between different image spaces. This method and the Dynamic Planning module of Pinnacle TPS were used to evaluate the adaptive radiotherapy plan of one patient with nasopharyngeal carcinoma, and these two methods were compared in terms of plan parameters and dosimetry. Results Compared with the Dynamic Planning module, this method maintained the consistency in the fore-and late-course plan parameters of the radiotherapy plan. The two methods had different positions of the isocenter, which caused the difference in dose distribution; however, if the two methods transferred the adaptive radiotherapy plan at the same isocenter, the dose distribution was exactly the same. Conclusions This method for the evaluation of adaptive radiotherapy plans is accurate, simple, convenient, and applicable to all versions of Pinnacle TPS, and it does not take up additional image storage space. This method increases the flexibility and precision of radiotherapy dose evaluation and provides a technical support for clinical practice and research. Key words: Treatment planning system; Dynamic planning; Adaptive radiotherapy