Inter-Modality Variation in Gross Tumor Volume Delineation in 18{sup left}FDG-PET Guided IMRT Treatment Planning for Lung Cancer

摘要

Rapid advances in 18{sup left}FDG-PET/CT technology and novel co-registration algorithms have created a strong interest in 18{sup left}FDG-PET/CT's application in intensity modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT). Accurate target volume delineation, particularly identification of pathologically positive lymph nodes, could translate into favorable treatment outcome. However, gross tumor volume (GTV) delineation on both CT and 18{sup left}FDG-PET is very sensitive to observer variation. The objectives of the study were to investigate the inter-modality variation in gross tumor volume delineation defined by two imaging modalities for lung cancer: CT and 18{sup left}FDG-PET/CT and its dosimetric implications in intensity modulated radiation therapy (IMRT).