Room: Exhibit Hall
Purpose: The aim of this work is to study the dosimetric impact of leaf interdigitation in esophagus cancer dynamic IMRT treatment planning.
Methods: 20 previously treated esophagus cancer patients were re-planned for fixed-field dynamic intensity-modulated radiation therapy (dMLC) with and without leaf interdigitation using Monaco 5.1 TPS on the Elekta Synergy linear accelerator. The PTV of EC contained esophagus gross target volume (GTV) and the positive neck lymph nodes. The prescription dose of PTV was 60Gy/20 fractions. Several dosimetric variables, such as PTV coverage, OAR sparing, delivery efficiency and optimization time, were evaluated for each plan.
Results: Interdigitation did not improve the coverage, HI and CI for PTV. Regarding OARs, sparing was equivalent with and without interdigitation. However, interdigitation shown an increase in MUs and segments. Meanwhile, leaf interdigitation saved the optimization time.
Conclusion: This study shows that leaf interdigitation does not improve plan quality when performing dMLC treatment plan for esophagus cancer. However, it influences delivery efficiency and optimization time. Interdigitation may gain efficiency for dosimetrist when designing the esophagus cancer dMLC plans.
Not Applicable / None Entered.
Not Applicable / None Entered.