title: Reliability of PET/CT Shape and Heterogeneity Features in Functional and Morphologic Components of Non-Small Cell Lung Cancer Tumors: A Repeatability Analysis in a Prospective Multicenter Cohort.
abstract: The main purpose of this study was to assess the reliability of shape and heterogeneity features in both the PET and the low-dose CT components of PET/CT. A secondary objective was to investigate the impact of image quantization.Methods:A Health Insurance Portability and Accountability Act-compliant secondary analysis of deidentified prospectively acquired PET/CT test-retest datasets of 74 patients from multicenter Merck and American College of Radiology Imaging Network trials was performed. Metabolically active volumes were automatically delineated on PET with a fuzzy locally adaptive bayesian algorithm. Software was used to semiautomatically delineate the anatomic volumes on the low-dose CT component. Two quantization methods were considered: a quantization into a set number of bins (quantization B) and an alternative quantization with bins of fixed width (quantization W). Four shape descriptors, 10 first-order metrics, and 26 textural features were evaluated. Bland-Altman analysis was used to quantify repeatability. Features were subsequently categorized as very reliable, reliable, moderately reliable, or poorly reliable with respect to the corresponding volume variability.Results:Repeatability was highly variable among features. Numerous metrics were identified as poorly or moderately reliable. Others were reliable or very reliable in both modalities and in all categories (shape and first-, second-, and third-order metrics). Image quantization played a major role in feature repeatability. Features were more reliable in PET with quantization B, whereas quantization W showed better results in CT.Conclusion:The test-retest repeatability of shape and heterogeneity features in PET and low-dose CT varied greatly among metrics. The level of repeatability also depended strongly on the quantization step, with different optimal choices for each modality. The repeatability of PET and low-dose CT features should be carefully considered when selecting metrics to build multiparametric models.
authors.affiliation: Laboratory of Medical Information Processing, INSERM UMR 1101, IBSAM, University of Brest, Brest, France Marie-Charlotte.Desseroit@etudiant.univ-brest.fr.|Medical School, University of Poitiers, Poitiers, France.
authors.forename: Marie-Charlotte
authors.initials: MC
authors.lastname: Desseroit
authors.affiliation: Medical School, University of Poitiers, Poitiers, France.|Nuclear Medicine, CHU Milétrie, Poitiers, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Tixier
authors.affiliation: Memorial Sloan Kettering Cancer Center, New York, New York; and.
authors.forename: Wolfgang A
authors.initials: WA
authors.lastname: Weber
authors.affiliation: Mallinckrodt Institute of Radiology and the Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri.
authors.forename: Barry A
authors.initials: BA
authors.lastname: Siegel
authors.affiliation: Medical School, University of Poitiers, Poitiers, France.|Nuclear Medicine, CHU Milétrie, Poitiers, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Cheze Le Rest
authors.affiliation: Laboratory of Medical Information Processing, INSERM UMR 1101, IBSAM, University of Brest, Brest, France.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Visvikis
authors.affiliation: Laboratory of Medical Information Processing, INSERM UMR 1101, IBSAM, University of Brest, Brest, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Hatt
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014481:United States
keywords: PET/CT; radiomics; repeatability; texture analysis