UNLABELLED PET can be used to monitor response during chemotherapy and assess biologic target volumes for radiotherapy. Previous simulation studies have shown that the performance of various automatic or semiautomatic tumor delineation methods depends on image characteristics. The purpose of this study was to assess test-retest variability of tumor delineation methods, with emphasis on the effe...

Introduction: Tumor volume delineation is the most important step in the radiation treatment planning. In this study the impact of PET/CT data on the tumor delineation precision of non-small cell lung cancer (NSCLC) was investigated. Methods: PET/CT images of 20 patients with primary NSCLC were obtained and imported to the treatment planning system for im...

In the thorax, the extent of tumor may be more accurately defined with the addition of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) to computed tomography (CT). This led to the increased utility of FDG-PET or PET/CT in the treatment planning of radiotherapy for non-small cell lung cancer (NSCLC). The inclusion of FDG-PET information in target volume delineation not only imp...

Introduction: Lung cancer is one of the most common causes of cancer-related deaths worldwide. Nowadays PET/CT plays an essential role in radiotherapy planning specially for lung tumors as it provides anatomical and functional information simultaneously that is effective in accurate tumor delineation. The optimal segmentation method has not been introduced yet, however several ...

Background: Breast conserving surgery (BCS) followed by radiotherapy (RT) has been widely accepted as the standard treatment in early stages of invasive breast cancer. The standard technique of RT includes whole breast irradiation (WBI). Additional tumor bed boost irradiation has also an important role in the local tumor control. But there are various controversial delivery methods. The aim of ...

BACKGROUND Metabolic tumor volume assessment using positron-emission tomography [PET] may be of interest for both target volume definition in radiotherapy and monitoring response to therapy. It has been reported, however, that metabolic volumes derived from images of metabolic rate of glucose (generated using Patlak analysis) are smaller than those derived from standardized uptake value [SUV] i...

Radiotherapy is a tumor treatment process using high dose of radiation. Hence, it is essential that radiotherapy is carefully planned with a Treatment Planning System (TPS). The first step in TPS is delineation that aims to get a better picture of the tumor and the target volume value. This research investigated volume target delineation for brain tumor against the MRI image of the head in axia...

Radiation therapy for cervical cancer involves a team of specialists, including diagnostic radiologists (DRs), radiation oncologists (ROs), and medical physicists (MPs), to optimize imaging-based radiation therapy planning. The purpose of the study was to investigate the interobserver variations in tumor delineation on MR images of cervical cancer within the same and among different specialties...

The success of radiotherapy depends on the accurate delineation of the clinical target volume. The delineation of the lymph node regions has most impact, especially for tumors in the head and neck region. The purpose of this article was the development an atlas for the delineation of the clinical target volume for patients, who should receive radiotherapy for a tumor of the head and neck region...

BACKGROUND Accurate tumor bed delineation after breast-conserving surgery is important. However, consistency among observers on standard postoperative radiotherapy planning CT is low and volumes can be large due to seroma formation. A preoperative delineation of the tumor might be more consistent. Therefore, the purpose of this study was to determine the consistency of preoperative target volum...