title: Test-retest reproducibility analysis of lung CT image features.
abstract: Quantitative size, shape, and texture features derived from computed tomographic (CT) images may be useful as predictive, prognostic, or response biomarkers in non-small cell lung cancer (NSCLC). However, to be useful, such features must be reproducible, non-redundant, and have a large dynamic range. We developed a set of quantitative three-dimensional (3D) features to describe segmented tumors and evaluated their reproducibility to select features with high potential to have prognostic utility. Thirty-two patients with NSCLC were subjected to unenhanced thoracic CT scans acquired within 15 min of each other under an approved protocol. Primary lung cancer lesions were segmented using semi-automatic 3D region growing algorithms. Following segmentation, 219 quantitative 3D features were extracted from each lesion, corresponding to size, shape, and texture, including features in transformed spaces (laws, wavelets). The most informative features were selected using the concordance correlation coefficient across test-retest, the biological range and a feature independence measure. There were 66 (30.14%) features with concordance correlation coefficient ≥ 0.90 across test-retest and acceptable dynamic range. Of these, 42 features were non-redundant after grouping features with R (2) Bet ≥ 0.95. These reproducible features were found to be predictive of radiological prognosis. The area under the curve (AUC) was 91% for a size-based feature and 92% for the texture features (runlength, laws). We tested the ability of image features to predict a radiological prognostic score on an independent NSCLC (39 adenocarcinoma) samples, the AUC for texture features (runlength emphasis, energy) was 0.84 while the conventional size-based features (volume, longest diameter) was 0.80. Test-retest and correlation analyses have identified non-redundant CT image features with both high intra-patient reproducibility and inter-patient biological range. Thus making the case that quantitative image features are informative and prognostic biomarkers for NSCLC.
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: Yoganand
authors.initials: Y
authors.lastname: Balagurunathan
authors.forename: Virendra
authors.initials: V
authors.lastname: Kumar
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Gu
authors.forename: Jongphil
authors.initials: J
authors.lastname: Kim
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Dmitry B
authors.initials: DB
authors.lastname: Goldgof
authors.forename: Lawrence O
authors.initials: LO
authors.lastname: Hall
authors.forename: Rene
authors.initials: R
authors.lastname: Korn
authors.forename: Binsheng
authors.initials: B
authors.lastname: Zhao
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Schwartz
authors.forename: Satrajit
authors.initials: S
authors.lastname: Basu
authors.forename: Steven
authors.initials: S
authors.lastname: Eschrich
authors.forename: Robert A
authors.initials: RA
authors.lastname: Gatenby
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Gillies
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D019540:Area Under Curve; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008168:Lung / Q000000981:diagnostic imaging; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*