Enhancing Radiotherapy for Locally Advanced Non-Small Cell Lung Cancer Patients with iCE, a Novel System for Automated Multi-Criterial Treatment Planning Including Beam Angle Optimization

Abstract

In this study, the novel iCE radiotherapy treatment planning system (TPS) for automated multi-criterial planning with integrated beam angle optimization (BAO) was developed, and applied to optimize organ at risk (OAR) sparing and systematically investigate the impact of beam angles on radiotherapy dose in locally advanced non-small cell lung cancer (LA-NSCLC). iCE consists of an in-house, sophisticated multi-criterial optimizer with integrated BAO, coupled to a broadly used commercial TPS. The in-house optimizer performs fluence map optimization to automatically generate an intensity-modulated radiotherapy (IMRT) plan with optimal beam angles for each patient. The obtained angles and dose-volume histograms are then used to automatically generate the final deliverable plan with the commercial TPS. For the majority of 26 LA-NSCLC patients, iCE achieved improved heart and esophagus sparing compared to the manually created clinical plans, with significant reductions in the median heart Dmean (8.1 vs. 9.0 Gy, p = 0.02) and esophagus Dmean (18.5 vs. 20.3 Gy, p = 0.02), and reductions of up to 6.7 Gy and 5.8 Gy for individual patients. iCE was superior to automated planning using manually selected beam angles. Differences in the OAR doses of iCE plans with 6 beams compared to 4 and 8 beams were statistically significant overall, but highly patient-specific. In conclusion, automated planning with integrated BAO can further enhance and individualize radiotherapy for LA-NSCLC.

Automated multi-criterial planning with beam angle optimization to establish non-coplanar VMAT class solutions for nasopharyngeal carcinoma

“…All plans used for this study were automatically generated with Erasmus-iCycle [14,15]. For many tumor sites, this system has demonstrated superiority of automatically generated plans, over manually generated plans [14,[16][17][18][19][20][21][22][23][24][25][26][27].…”

“…The system has an option for integrated optimization of beam intensity profiles and (non-coplanar) beam angle directions [8,11,12,15,[26][27][28][29][30][31][32][33], which was used in this study. Erasmus-iCycle generates Pareto-optimal and clinically favorable plans by applying an appropriate treatment site specific configuration ('wish-list') [15,17,34], containing hard constraints that can never be violated, and objectives that are optimized in order of priority.…”

“…Erasmus-iCycle uses fluence map optimization (FMO) for automated plan generation. Subsequently, a commercial treatment planning system is used for automated segmentation of the generated FMO plan, mimicking the FMO dose distribution [11,14,[27][28][29]. For VMAT, an FMO plan with equi-angular IMRT beams is generated with Erasmus-iCycle, which is then automatically segmented in the commercial TPS for VMAT delivery [14,[16][17][18][19][20][21][22][23][25][26][27]29].…”

“…Automatically generated Erasmus-iCycle plans were converted into clinically deliverable segmented plans using the Monaco treatment planning system (TPS), version 5.11 (Elekta AB, Stockholm, Sweden). These conversions were fully automatically performed, using patient-specific Monaco templates, automatically derived from the patient-specific Erasmus-iCycle FMO dose distributions [8,12,15,21,[26][27][28][29][30][31][32][33][34][35][36].…”

Radiation Therapy in Thoracic Tumors: Recent Trends and Current Issues

“…An example of an automated multi-criterial treatment planning system (TPS) is the Erasmus-iCycle with integrated beam angle optimization, developed at the Erasmus University Medical Center. In [ 7 ], the Erasmus-iCycle was coupled with the commercial TPS Eclipse (Varian Medical Systems, Palo Alto, CA, USA), obtaining the novel “iCE” system. Its potential was shown in Locally Advanced Non-Small-Cell Lung Cancer (NSCLC) patients, where an improved sparing of the heart and esophagus was observed for most of the analyzed patients, with significant reductions in heart and esophagus dosimetric parameters predictive for toxicity.…”