Advantage of biological over physical optimization in prostate cancer?

The biological effects of an applied dose can be accounted for by using biological objective functions with IMRT. A commonly used concept is the generalized equivalent uniform dose (gEUD), developed by Niemierko. Unlike the equivalent uniform dose (EUD) which is defined for tumor only, the gEUD can be used for both target volume and organs-at-risk (OAR).

Commissioning of volumetric modulated arc therapy (VMAT) in a dual-vendor environment.

Methods and results for commissioning of the complete VMAT delivery chain are presented for the combination of Nucletron's Oncentra MasterPlan® v3.3 with Elekta's Mosaiq® v1.6 and SynergyS® linac.

Evaluation of volumetric modulated arc therapy (VMAT) with Oncentra MasterPlan® for the treatment of head and neck cancer.

Background: Several comparison studies have shown the capability of VMAT to achieve similar or better plan quality as IMRT, while reducing the treatment time. The experience of VMAT in a multi vendor environment is limited. We compared the plan quality and performance of VMAT to IMRT and we investigate the effects of varying various user-selectable parameters.

Improving the performance of direct Monte Carlo optimization for large tumor volumes.

Direct Monte Carlo Optimization (DMCO) is a powerful method for dose optimization with Monte Carlo accuracy and direct aperture optimization with simulated annealing. Recently, we presented quasi intensity modulated arc therapy (qIMAT), a step-and-shoot technique that simulates a rotational technique by using a high number of beams and reducing the number of segments. In the present work, we applied a combination of both techniques to optimize an anal cancer case.

Quasi-IMAT technique and secondary cancer risk in prostate cancer.

Background And Purpose: Estimates of secondary cancer risk after radiotherapy are relevant for treatment-planning comparison. Recently, the authors investigated the potential of a step-and-shoot intensity-modulated arc therapy (quasi-IMAT [qIMAT]) to improve the intensity-modulated radiotherapy (IMRT) plan quality. Here, the effect of the primary dose distribution, photon scatter and neutron dose, and the risk of secondary malignancies after qIMAT technique were analyzed and compared to IMRT.

Quasi-IMAT study with conventional equipment to show high plan quality with a single gantry arc.

Background And Purpose: : Nowadays, intensity-modulated arc therapy (IMAT) for clinical use is mostly based on forward planning. The aim of this work is to investigate the potential of a step-and-shoot quasi-IMAT (qIMAT) technique to improve plan quality.

Material And Method: : qIMAT plans with 18 and 36 beams were generated with a total number of 36 segments.