ESTRO 2021 Abstract Book

S1621

ESTRO 2021

PO-1900 TPS Scripting to automate the prostate treatment planning process: does it reduce plan quality? S. Hofer 1 , M. Maffei 2 , P. Ferrari 1 , J. Waskiewicz 3 , M. Haller 4 1 Südtiroler Sanitätsbetrieb, Dienst für medizinische Strahlenphysik, Bozen, Italy; 2 Südtiroler Sanitätsbetrieb, Dienst für onkologische Strahlentherapie, Bozen, Italy; 3 Südtiroler Sanitätsbetrieb, Dienst für onkologische Strahlentherapie , Bozen, Italy; 4 Südtiroler Sanitätsbetrieb, Dienst für medizinische Strahlenphysik , Bozen, Italy Purpose or Objective In the planning process of prostate treatments there are a series of steps able to be done by an automatic TPS scripting tool. The aim of this study is to test the feasibility to use TPS scripts for prostate treatment planning and to evaluate the resulting plan quality compared to the quality of manual planned treatments. Materials and Methods The Raystation (v9.0, Raysearch Laboratories) treatment planning system uses Iron Python as scripting language. It was used to implement a planning process for prostate treatments where several steps have been automized. The prostate plans with two treatment phases where created with a first Vmat phase and a 3DCRT boost phase. If the corresponding plan was not able to fulfil the clinical goals 1 there was automatically build a plan with a Vmat boost phase which should further reduce the dose to the organs at risk. The sequence of the scripted process corresponds more or less to the maual planning procedure in our institution. The following graph shows the corresponding workflow:

Twelve prostate treatments have been evaluated retrospectively and the manual created treatment plan has been compared with the plan created by the scripting tool. Results The evaluation showed no significant difference (paired bilateral T test - p < 0.05) in target coverage and doses to organs at risk (rectum , bladder, anal canal, penile bulb). Also regarding the modulation complexity 2 there was no statistical difference between the two plan categories.