Journal article
Interobserver and intermodality variability in GTV delineation on simulation CT, FDG-PET, and MR Images of Head and Neck Cancer
Jacobs journal of radiation oncology, Vol.1(1), p.006
09/2014
PMCID: PMC4283948
PMID: 25568889
Abstract
To compare the interobserver and intermodality differences in image-based identification of head and neck primary site gross tumor volumes (GTV). Modalities compared include: contrast-enhanced CT, F-18 fluorodeoxyglucose positron emission tomography (PET/CT) and contrast-enhanced MRI.
Fourteen patients were simulated after immobilization for all 3 imaging modalities (CT, PET/CT, MRI). Three radiation oncologists (RO) contoured GTVs as seen on each modality. The GTV was contoured first on the contrast-enhanced CT (considered the standard), then on PET/CT, and finally on post-contrast T1 MRI. Interobserver and intermodality variability were analyzed by volume, intersection, union, and volume overlap ratio (VOR).
Analysis of RO contours revealed the average volume for CT-, PET/CT-, and MRI-derived GTVs were 45cc, 35cc and 49cc, respectively. In 93% of cases PET/CT-derived GTVs had the smallest volume and in 57% of cases MRI-derived GTVs had the largest volume. CT showed the largest variation in target definition (standard deviation amongst observers 35%) compared to PET/CT (28%) and MRI (27%). The VOR was largest (indicating greatest interobserver agreement) in PET/CT (46%), followed by MRI (36%), followed by CT (34%). For each observer, the least agreement in GTV definition occurred between MRI & PET/CT (average VOR = 41%), compared to CT & PET/CT (48%) and CT & MRI (47%).
A nonsignificant interobserver difference in GTVs for each modality was seen. Among three modalities, CT was least consistent, while PET/CT-derived GTVs had the smallest volumes and were most consistent. MRI combined with PET/CT provided the least agreement in GTVs generated. The significance of these differences for head & neck cancer is important to explore as we move to volume-based treatment planning based on multi-modality imaging as a standard method for treatment delivery.
Details
- Title: Subtitle
- Interobserver and intermodality variability in GTV delineation on simulation CT, FDG-PET, and MR Images of Head and Neck Cancer
- Creators
- Carryn M Anderson - Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USAWenqing Sun - Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USAJohn M Buatti - Department of Biostatistics, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USAJoan E Maley - Department of Human Oncology, University of Wisconsin, Madison, Wisconsin, USABruno PoliceniSarah L MottJohn E Bayouth
- Resource Type
- Journal article
- Publication Details
- Jacobs journal of radiation oncology, Vol.1(1), p.006
- PMID
- 25568889
- PMCID
- PMC4283948
- NLM abbreviation
- Jacobs J Radiat Oncol
- ISSN
- 2376-9424
- Publisher
- United States
- Grant note
- P30 CA086862 / NCI NIH HHS U01 CA140206 / NCI NIH HHS
- Language
- English
- Date published
- 09/2014
- Academic Unit
- Radiology; Oral Pathology, Radiology and Medicine; Radiation Oncology; Neurosurgery; Otolaryngology
- Record Identifier
- 9984040531302771
Metrics
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