title: A novel magnetic resonance imaging segmentation technique for determining diffuse intrinsic pontine glioma tumor volume.
abstract: OBJECTIVE Accurately determining diffuse intrinsic pontine glioma (DIPG) tumor volume is clinically important. The aims of the current study were to 1) measure DIPG volumes using methods that require different degrees of subjective judgment; and 2) evaluate interobserver agreement of measurements made using these methods. METHODS Eight patients from a Phase I clinical trial testing convection-enhanced delivery (CED) of a therapeutic antibody were included in the study. Pre-CED, post-radiation therapy axial T2-weighted images were analyzed using 2 methods requiring high degrees of subjective judgment (picture archiving and communication system [PACS] polygon and Volume Viewer auto-contour methods) and 1 method requiring a low degree of subjective judgment (k-means clustering segmentation) to determine tumor volumes. Lin's concordance correlation coefficients (CCCs) were calculated to assess interobserver agreement. RESULTS The CCCs of measurements made by 2 observers with the PACS polygon and the Volume Viewer auto-contour methods were 0.9465 (lower 1-sided 95% confidence limit 0.8472) and 0.7514 (lower 1-sided 95% confidence limit 0.3143), respectively. Both were considered poor agreement. The CCC of measurements made using k-means clustering segmentation was 0.9938 (lower 1-sided 95% confidence limit 0.9772), which was considered substantial strength of agreement. CONCLUSIONS The poor interobserver agreement of PACS polygon and Volume Viewer auto-contour methods highlighted the difficulty in consistently measuring DIPG tumor volumes using methods requiring high degrees of subjective judgment. k-means clustering segmentation, which requires a low degree of subjective judgment, showed better interobserver agreement and produced tumor volumes with delineated borders.
authors.affiliation: Weill Medical College of Cornell University;
authors.forename: Ranjodh
authors.initials: R
authors.lastname: Singh
authors.affiliation: Departments of 2 Neurological Surgery.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Departments of 5 Radiology.
authors.forename: Jamie
authors.initials: J
authors.lastname: Tisnado
authors.affiliation: Departments of 5 Radiology.
authors.forename: Sofia
authors.initials: S
authors.lastname: Haque
authors.affiliation: Departments of 5 Radiology.|Medical Physics, and.
authors.forename: Kyung K
authors.initials: KK
authors.lastname: Peck
authors.affiliation: Departments of 5 Radiology.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Young
authors.affiliation: Radiology and.
authors.forename: Apostolos John
authors.initials: AJ
authors.lastname: Tsiouris
authors.affiliation: Departments of 5 Radiology.|Medical Physics, and.
authors.forename: Sunitha B
authors.initials: SB
authors.lastname: Thakur
authors.affiliation: Departments of 2 Neurological Surgery.|Pediatrics, Weill Medical College of Cornell University; and.|Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Mark M
authors.initials: MM
authors.lastname: Souweidane
mesh_terms: D000818:Animals; D058846:Antibodies, Monoclonal, Murine-Derived / Q000008:administration & dosage; D020295:Brain Stem Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D005910:Glioma / Q000000981:diagnostic imaging* / Q000628:therapy; D006801:Humans; D008297:Male; D047368:Tumor Burden
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived
keywords: CCC = concordance correlation coefficient; CED = convection-enhanced delivery; DIPG = diffuse intrinsic pontine glioma; MSKCC = Memorial Sloan Kettering Cancer Center; PACS = picture archiving and communication system; ROI = region of interest; diffuse intrinsic pontine glioma; k-means clustering; magnetic resonance imaging; oncology; tumor volume determination