Comparison of Planned Dose Distributions Calculated by Monte Carlo and Ray-Trace Algorithms for the Treatment of Lung Tumors With CyberKnife: A Preliminary Study in 33 Patients

We establish that changing the treatment plan calculation algorithm from EPL to MC can produce large differences in target and critical organs' dose coverage. The observed discrepancies are larger for plans using smaller collimator sizes and have strong dependency on the anatomical relationship of target-critical structures.