OBJECTS To introduce a new method for generating the clinical target volume (CTV) from gross tumor volume (GTV) using the geodesic distance calculation for glioma. METHODS One glioblastoma patient was enrolled. The GTV and natural barriers were contoured on each slice of the computer tomography (CT) simulation images. Then, a graphic processing unit based on a parallel Euclidean distance tran...

Purpose: To compare tumour bed (TB) volumes delineated using MRI plus CT/clips (MRCT) with those delineated using CT/clips-alone in post-lumpectomy breast cancer patients positioned prone, and to determine the value of MRCT for planning partial breast radiotherapy (PBI). Materials/ Methods: 30 women with breast cancer each had 6-12 titanium-clips secured in the excision cavity walls at lumpecto...

THE IMPORTANCE OF CLINICAL TARGET VOLUME FOR RADIATION THERAPY IN RECTAL CANCER (Abstract): Neoadjuvant chemoradiotherapy is the standard treatment in locally advanced rectal cancer and it was demonstrated that radiation therapy associated with total mesorectal excision reduces local recurrence rate. It is very important to precisely determine the area that is subjected to radiation, in order t...

INTRODUCTION In breast conserving radiotherapy differences of target volume delineations between observers do occur. We evaluated whether delineations based on co-registered computed tomography (CT) and magnetic resonance (MR) imaging may result in an improved consistency between observers. We used the delineation conformity index (CI) to compare clinical target volumes of glandular breast tiss...

The Gaussian error function model, containing pairs of error and complementary error functions, was used to carry out cumulative dose-volume histogram (cDVH) analysis on prostate intensity modulated radiation therapy (IMRT) plans with interfraction prostate motion. Cumulative DVHs for clinical target volumes (CTVs) shifted in the anterior-posterior directions based on a 7-beam IMRT plan were ca...

BACKGROUND AND PURPOSE Brachytherapy (BT) plays a crucial role in the management of invasive cervix cancer from stage I to IV. Intracavitary techniques are based on afterloading devices, with different types of applicators. CT and/or MRI compatible applicators allow a sectional image based approach with a better assessment of gross tumour volume (GTV) and definition and delineation of target vo...

This study evaluated a method for prostate intensity-modulated radiation therapy (IMRT) based on edge-enhanced (EE) intensity in the presence of intrafraction organ deformation using the data of 37 patients treated with step-and-shoot IMRT. On the assumption that the patient setup error was already accounted for by image guidance, only organ deformation over the treatment course was considered....

This study aimed to identify factors predictive of the benefit of respiratory-gated radiotherapy. Three plans were created for 25 patients with non-small cell lung cancer, simulating the following 3 treatment scenarios. Protocol 1 was non-gated and the lung dose was calculated using 4-s slow CT (PnA), protocol 2 was also non-gated and the lung dose was calculated by CT at the end-expiration pha...

The planning target volume (PTV) includes the clinical target volume (CTV) to be irradiated and a margin to account for uncertainties in the treatment process. Uncertainties in miniature multileaf collimator (mMLC) leaf positioning, CT scanner spatial localization, CT-MRI image fusion spatial localization, and Gill-Thomas-Cosman (GTC) relocatable head frame repositioning were quantified for the...

PURPOSE Setup, range, and anatomical uncertainties influence the dose delivered with intensity modulated proton therapy (IMPT), but clinical quantification of these errors for oropharyngeal cancer is lacking. We quantified these factors and investigated treatment fidelity, that is, robustness, as influenced by adaptive planning and by applying more beam directions. METHODS AND MATERIALS We us...