Reproducibility of "Intelligent" Contouring of Gross Tumor Volume in Non-Small-Cell Lung Cancer on PET/CT Images Using a Standardized Visual Method

Abstract

Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly used for delineating gross tumor volume (GTV) in non-small-cell lung cancer (NSCLC). The methodology for contouring tumor margins remains controversial. We developed a rigorous visual protocol for contouring GTV that uses all available clinical information and studied its reproducibility in patients from a prospective PET/CT planning trial. Methods and Materials: Planning PET/CT scans from 6 consecutive patients were selected. Six "observers" (two radiation oncologists, two nuclear medicine physicians, and two radiologists) contoured GTVs for each patient using a predefined protocol and subsequently recontoure..