Comparison of volumetric methods for tumor measurements on two and three dimensional MRI in adult glioblastoma.
BACKGROUND
Change in tumor size is a frequent endpoint in cancer clinical trials, but whether change in size should be measured using volume on two-dimensional (2D) or three-dimensional (3D) images is not certain. We compared volumetric measurements on post-contrast 2D and high-resolution 3D T1-weighted MR images (T1WI) in evaluating tumor response in glioblastoma multiforme (GBM).


METHODS
Tumor volume measurements were performed on 86 MRI studies from 37 adult patients with GBM on post-contrast 5 mm 2D T1WI and isotropic high-resolution T1WI. The means of the two volumes were compared and their association was analyzed.


RESULTS
There is no significant difference between volumes measured on 2D and 3D in 86 scans (Z = 0.63, p = 0.53), and a high correlation was revealed between them (r = 0.95, 95% CI: 0.93-0.97, p < 0.001). When the percentage changes were categorized into traditional tumor response criteria (complete response/partial response/stable disease/progressive disease), the kappa coefficient between the volume on 2D and volume on 3D was 0.80 (95% CI: 0.57-1.03, p < 0.05) with an overall agreement of 84%.


CONCLUSIONS
Volume on post-contrast 2D T1WI appears comparable to volume on 3D T1WI and should be a practical alternative to volume on 3D in evaluating tumor response.
Department of Radiology, Henan Provincial People's Hospital, 7 Weiwu Rd., Zhengzhou, Henan, 450003, China.
Mei-Yun
MY
Wang
Jing-Liang
JL
Cheng
Yan-Hong
YH
Han
Yong-Li
YL
Li
She-Wei
SW
Dou
Feng-Shan
FS
Yan
Da-Peng
DP
Shi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001932:Brain Neoplasms / Q000473:pathology*; D005260:Female; D005909:Glioblastoma / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity