During radiotherapy for gastric lymphoma, it is difficult to protect the liver and kidneys in cases where there is considerable overlap between these organs and the target volume. This study was conducted to compare the three radiotherapy planning techniques of four-fields 3D conformal radiotherapy (3DCRT), half-field radiotherapy (the half-beam method) and intensity-modulated radiotherapy (IMR...

AIMS AND BACKGROUND Conventional radiotherapy in inoperable cholangiocarcinoma is limited by radiotolerance of the surrounding tissues. The aim of our dosimetric study was an evaluation of intensity-modulated radiotherapy in the treatment of inoperable bile duct carcinoma. METHODS Four patients with inoperable cholangiocarcinoma treated by self-expandable stent placed to the biliary tree and ...

In High Dose Rate (HDR) brachytherapy the conventional dose optimization algorithms consider the multiple objectives in form of an aggregate function which combines individual objectives into a single utility value. As a result, the optimization problem becomes single objective, prior to optimization. Up to 300 parameters must be optimized satisfying objectives which are often competing. We use...

PURPOSE To compare low dose volume and integral dose of various rotational arc radiation therapy modalities, including helical tomotherapy (HT) and other volumetric modulated arc therapies (VMAT). METHODS A digital cylindrical phantom and an anthropomorphic pelvic phantom were used in the study. HT treatment was planned on TomoTherapy Planning Station (Accuray) and VMAT plans were generated o...

We created volumetric modulated arc therapy (VMAT) plans for 31 prostate cancer patients using one of three treatment planning systems (TPSs)--ERGO++, Monaco, or Pinnacle--and then treated those patients. A dose of 74 Gy was prescribed to the planning target volume (PTV). The rectum, bladder, and femur were chosen as organs at risk (OARs) with specified dose-volume constraints. Dose volume hist...

Plans of patients with prostate tumor have been studied. These patients have been scanned in the CT simulator and the images have been sent to the Focal, the system where the doctor delineates the tumor and the organs at risk. After that in the treatment planning system XiO there are created for the same patients three dimensional conformal and intensity modulated radiotherapy treatment plans. ...

PURPOSE Adjuvant radiotherapy of breast cancer using a photon tangential field incurs a risk of late heart and lung toxicity. The use of free breathing (FB), expiration breath hold (EBH), and deep inspiration breath hold (DIBH) during tangential breast radiotherapy as a means of reducing irradiated lung and heart volume was evaluated. METHODS In 10 women with left-sided breast cancer (mean ag...

PURPOSE The objective of this study was to evaluate the dosimetric feasibility of using hippocampus (HPC) sparing intensity-modulated radiotherapy (IMRT) in patients with locally advanced nasopharyngeal carcinoma (NPC). MATERIALS/METHODS Eight cases of either T3 or T4 NPC were selected for this study. Standard IMRT treatment plans were constructed using the volume and dose constraints for the...

BACKGROUND Research has reported relationships between 3-dimensional (3D) radiation dose to head and neck structures and consequential swallowing/nutritional outcomes. However, this evidence is preliminary. The current study aimed to identify which reported dose constraints identified functional impairment at 6 months posttreatment. METHODS Dose constraints with reported relationships to swal...

BACKGROUND To dosimetrically evaluate the effect of reduced margin radiotherapy on hippocampal dose for glioblastoma multiforme (GBM) patients. METHODS GBM patients enrolled on the Radiation Therapy Oncology Group (RTOG) 0825 trial at our institution were identified. Standard RTOG 0825 expansions were 2 cm + 3-5 mm from the gross tumor volume (GTV) to the clinical tumor volume (CTV) and from ...