PURPOSE The purpose of this study was to develop and test planning dose constraint templates for tumor and normal structures in the treatment of nasopharyngeal carcinoma (NPC) using a specific commercial inverse treatment planning system. METHODS AND MATERIALS Planning dose constraint templates were developed based on the analyses of dose-volume histograms (DVHs) of tumor targets and adjacent...

introduction: brachytherapy is a type of radiotherapy in which radioactive sources are used in proximity of tumors normally for treatment of malignancies in the head, prostate and cervix. materials and methods: the cs-137 selectron source is a low-dose-rate (ldr) brachytherapy source used in a remote afterloading system for treatment of different cancers. this system uses active and inactive sp...

Introduction: Concurrent chemoradiotherapy (CRT) is a standard treatment method for patients with carcinoma of cervix. Despite admirable therapeutic results, acute hematologic toxicity (HT) is common with this regimen. Many studies evaluate the relationship between the bone marrow dosimetric parameters and the severity of HT and result shown that the low dose of bone marrow wou...

BACKGROUND The newest release of the Eclipse (Varian) treatment planning system (TPS) includes an optimizing engine for Elekta volumetric-modulated arc therapy (VMAT) planning. The purpose of this study was to evaluate this new algorithm and to compare it to intensity-modulated radiation therapy (IMRT) for various disease sites by creating single- and double-arc VMAT plans. METHODS A total of...

Introduction: The use of electrons in the electron therapy to destroy tumoral tissue is dedicated significant contribution of different methods of radiation therapy. Scattered radiation due to exited electrons of the applicator affect the dose out of the field in the patient's normal tissue. The aim of this study is to determine the peripheral dose outside the applicator in the...