Introduction: Radiotherapy is one of the treatment options for locally advanced prostate cancer, however with standard radiation doses it is not always very effective. One of the strategies to improve the efficiency of radiotherapy is increasing the dose. In this study to increase tumor local control rates a new radiotherapy method, known as dose painting (DP) was investigated....

PURPOSE The 4π static non-coplanar radiotherapy delivery technique has demonstrated better normal tissue sparing and dose conformity than the clinically used volumetric modulated arc therapy (VMAT). It is unclear whether this is a fundamental limitation of VMAT delivery or the coplanar nature of its typical clinical plans. The dosimetry and the limits of normal tissue toxicity constrained dose ...

AIM To create a presentation method of TCP and NTCP distributions calculated based on dose distribution for a selected CT slice. MATERIALS AND METHODS Three 24-bit colour maps - of dose distribution, delineated structures and CT information - were converted into m-by-n-by-3 data arrays, containing intensities of red, green, and blue colour components for each pixel. All calculations were perf...

We use robust optimization techniques to formulate an IMRT treatment planning problem in which the dose matrices are uncertain, due to both dose calculation errors and interfraction positional uncertainty of tumour and organs. When the uncertainty is taken into account, the original linear programming formulation becomes a second-order cone program. We describe a novel and efficient approach fo...

This study aims to evaluate the radiotherapy planning performance considering clinical results of glioblastoma multiforme (GBM)-treated patients from both physical and radiobiological perspectives. Radiotherapy plans are done for 20 with GBM tumors who have received radical VMAT treatment on Eclipse-13.5. Dosimetric evaluation metrics estimated compare two in terms TCP, NTCP, P+ context evaluat...

BACKGROUND To consolidate literature reports of serious late gastrointestinal toxicities after hypofractionated radiation treatment of pancreatic cancer and attempt to derive normal tissue complication probability (NTCP) parameters using the Lyman-Kutcher-Burman model. METHODS Published reports of late grade 3 or greater gastrointestinal toxicity after hypofractionated treatment of pancreatic...

IMRT plans generated in Eclipse use a fast algorithm to evaluate dose for optimization and a more accurate algorithm for a final dose calculation, the Analytical Anisotropic Algorithm. The use of a fast optimization algorithm introduces optimization convergence errors into an IMRT plan. Eclipse has a feature where optimization may be performed on top of an existing base plan. This feature allow...

background: to analyze the dosimetric and radio biologic advantages between intensity modulated radiotherapy (imrt) and 3 dimensional conformal radiotherapy (3dcrt) and selection of optimal photon energy for imrt treatments. material and methods: 24 patients with localized prostate carcinoma were planned for 3dcrt and imrt techniques. radiation dose of 54 gy with 2 gy/fraction, was planned to p...

PurposeCurative radiotherapy for nasopharyngeal carcinoma (NPC) can lead to acquired nasal cavity stenosis and atresia (ANCSA). As the first study investigate risk factors of ANCSA in a large cohort NPC patients, this article aims develop validate multivariate normal tissue complication probability (NTCP) model predict development establish nomogram clinical use.Methods materialsThe retrospecti...

We use a stochastic birth-death model for a population of cells to estimate the normal tissue complication probability (NTCP) under a particular radiotherapy protocol. We specifically allow for interaction between cells, via a nonlinear logistic growth model. To capture some of the effects of intrinsic noise in the population we develop several approximations of NTCP, using Kramers–Moyal expans...