Background
Previous automated planning approach studies for Raystation were limited to a specific anatomical site cancer or a single treatment technique. The purpose of this study is to develop an automated planning approach in Raystation and evaluate its feasibility and performance in multiple clinical application scenarios.
Methods
Sixty patients, including 20 nasopharyngeal carcinoma (NPC), 20 esophageal carcinoma (ESCA) and 20 rectal cancer (RECA), who were treated with volumetric-modulated arc therapy for NPC and RECA and intensity-modulated radiotherapy for ESCA, were retrospectively enrolled in this study. An automated planning approach (Ruiplan), consisting of five key modules: prescription and OAR identification module, auxiliary structure generation module, dose prediction and objectives setting module, beam configuration module, plan fine-turning module, was developed by using the scripting platform of Raystation. Radiotherapy plans were re-generated both automatically by using Ruiplan and manually by experienced physicists. Target coverage, organs at risk (OARs) sparing, and planning efficiency of the automated plans (APs) and manual plans (MPs) were statistically compared using paired student t-test.
Results
For target coverage, APs yielded superior dose homogeneity in NPC and RECA, compared to MPs, while maintaining similar dose conformity for all studied anatomical sites. For OARs sparing, APs led to significant improvement in most OARs sparing, compared to MPs. The max dose of the lens, eyes and optic nerves in NPC, the V20 and mean dose of lungs, the V30, V40 and mean dose of heart in ESCA, the V30, V50 of bowel and V30 of femoral heads in CRCA were significantly decreased on average in APs compared to MPs (P < 0.05). The average planning time required for APs was reduced by more than 43% compared with MPs. Despite the increased monitor units (MUs) for NPC and RECA in APs, the beam-on time of APs and MPs had no statistical difference. Both the MUs and beam-on time of APs were significantly lower than that of MPs in ESCA (P < 0.05).
Conclusions
The developed Ruiplan was capable of generating high-quality treatment plans that were comparable to the MPs created by experienced physicists, in a variety of treatment techniques and cancer sites studied.