This study investigated position dependence in planning target volume (PTV)-based and robust optimization plans using full-arc and partial-arc volumetric modulated arc therapy (VMAT). The gantry angles at the periphery, intermediate, and center CTV positions were 181°-180° (full-arc VMAT) and 181°-360° (partial-arc VMAT). A PTV-based optimization plan was defined by 5 mm margin expansion of the...

PURPOSE Locally recurring cervical cancer after surgery and adjuvant radiotherapy remains a major therapeutic challenge. This paper presents a new therapeutic technique for such patients: interstitial brachytherapy (BT) guided by real-time three-dimensional (3D) computed tomography (CT). MATERIAL AND METHODS Sixteen patients with recurrent cervical cancer after radical surgery and adjuvant ex...

PURPOSE To analyze dosimetric parameters of patients receiving adjuvant breast radiotherapy (RT) in the prone versus supine position. METHODS AND MATERIALS Forty-one out of 55 patients with pendulous breasts and candidates for adjuvant RT were enrolled in the study after informed consent. They underwent computed tomography (CT)-simulation in both prone and supine position. Target and non targ...

ID: 4975 Title: Modeling Dose Delivery Accuracy of IMRT Head-and-Neck Cancer Treatment Purpose: To evaluate the impact of internal organ variations on IMRT treatments of head-and-neck cancers using different daily alignment techniques. Method and Materials: Eleven head-and-neck cancer patients were imaged twice weekly during their course of treatment (141 CT scans total) using an integrated CT-...

Abstract Background Radiotherapy of gastric mucosa-associated lymphoid tissue (MALT) lymphoma should be delivered to the entire stomach with planning target volume (PTV) that accounts for variations in volume, respiratory movement, and patient set-up error. In this study, we evaluated whether use four-dimensional cone-beam computed tomography (4D-CBCT) reduces PTV. Methods Eight patients underw...

BACKGROUND To evaluate the impact of image-guided radiation therapy (IGRT) versus non-image-guided radiation therapy (non-IGRT) on the dose to the clinical target volume (CTV) and the cervical spinal cord during fractionated intensity-modulated radiation therapy (IMRT) for head-and-neck cancer (HNC) patients. MATERIAL AND METHODS For detailed investigation, 4 exemplary patients with daily con...

PURPOSE To evaluate dosimetric variations of planning target volume (PTV) on critical organs such as rectal wall, bladder and femoral head, when the patient size changes due to weight loss in prostate volumetric modulated arc therapy (VMAT). METHODS Three patients with small (32.0 cm3 ), medium (48.4 cm3 ) and large (86.5 cm3 ) prostate, selected from a group of 30 were planned for prostate V...

191 Background: Image guided radiation therapy (IGRT) corrects for the interfractional movements of the target/CTV. However, the anatomic changes of CTV, and movements of the adjacent organs, are not accounted for. By modifying an online adaptive radiation technique proposed by Li, we have clinically deployed a daily "real-time treatment planning" (RTP) technique for treatment of primary prosta...

PurposeMulticatheter interstitial brachytherapy (MIB) and external-beam (EB) radiotherapy are established partial-breast irradiation (PBI) techniques. Although EB-PBI is widely available, it requires extra irradiated margins for target uncertainties. We examined the impact of on dose–volume constraints as compared to MIB-PBI.Methods MaterialsAmong 653 patients receiving MIB-PBI between October ...

BACKGROUND Interstitial brachytherapy (ISBT) is an optional treatment for locally advanced gynecological tumours for which conventional intracavitary brachytherapy (ICBT) would result in suboptimal dose coverage. However, ISBT with Martinez Universal Perineal Interstitial Template (MUPIT), in which ~10-20 needles are usually applied, is more time-consuming and labor-intensive than ICBT alone, m...