Glioblastoma differ from many other tumors in the sense that they grow infiltratively into the brain tissue instead of forming a solid tumor mass with a defined boundary. Only the part of the tumor with high tumor cell density can be localized through imaging directly. In contrast, brain tissue infiltrated by tumor cells at low density appears normal on current imaging modalities. In current cl...

BACKGROUND The aim was to evaluate the geometric and corresponding dosimetric differences between two delineation strategies for head and neck tumors neighboring air cavities. METHODS Primary gross and clinical tumor volumes (GTV and CTV) of 14 patients with oropharynx or larynx tumors were contoured using a soft tissue window (S). In a second strategy, the same volumes were contoured with an...

Clinical target volume (CTV) delineation is crucial for tumor control and normal tissue protection. This study aimed to define the locoregional extension patterns of nasopharyngeal carcinoma (NPC) and to improve CTV delineation. Magnetic resonance imaging scans of 2366 newly diagnosed NPC patients were reviewed. According to incidence rates of tumor invasion, the anatomic sites surrounding the ...

PURPOSE 4D-PET/CT imaging is an excellent solution for reducing the breathing-induced effects in both CT and PET images. In 4D-PET/CT, 4D-CT images are selected to match those of 4D-PET phase by phase and the corresponding phases are used for attenuation correction in 4D-PET. However, the high radiation dose that patients acquire while undergoing 4D-CT imaging for diagnostic purposes remains a ...

introduction: acoustic transient cavitation is the primary mechanism of sonochemical reaction and has potential use for tumor treatment. in this study, the in vivo anti-tumor effect of simultaneous dual-frequency ultrasound at low-level intensity (isata < 6 w/cm2) was investigated in a spontaneous murine model of breast adenocarcinoma in balb/c mice. materials and methods: forty tumor bearing m...

PURPOSE Brain tumor radiotherapy requires the volume measurements and the localization of several individual brain structures. Any tool that can assist the physician to perform the delineation would then be of great help. Among segmentation methods, those that are atlas-based are appealing because they are able to segment several structures simultaneously, while preserving the anatomy topology....

Accurate radiation treatment delivery in non-small cell lung cancer is technically challenging. While significant improvements in imaging technology lead to improved tumor delineation, other challenges such as respiratory and cardiac-induced motion, setup inconsistencies, and volume changes and deformation result in significant uncertainties when it comes to targeting the tumor and minimizing n...

To evaluate the impact of 18F-FDG PET/CT on target volume delineation in gynaecological