Impact of Tumor Size and Tracer Uptake Heterogeneity in ¹⁸F-FDG PET and CT Non–Small Cell Lung Cancer Tumor Delineation

Abstract

Volumes based on CT images were larger than those based on PET images. Tumor size and tracer uptake heterogeneity have an impact on threshold-based methods, which should not be used for the delineation of cases of large heterogeneous NSCLC, as these methods tend to largely underestimate the spatial extent of the functional tumor in such cases. For an accurate delineation of PET volumes in NSCLC, advanced image segmentation algorithms able to deal with tracer uptake heterogeneity should be preferred.