Rectal cancer: MR imaging in local staging--is gadolinium-based contrast material helpful?

R.F. Vliegen, G.L. Beets, M.F. von Meyenfeldt, A.G. Kessels, E.E. Lemaire, J.M. van Engelshoven, R.G.H. Beets-Tan

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

PURPOSE: To determine retrospectively whether addition of gadolinium-enhanced T1-weighted magnetic resonance (MR) sequence to T2-weighted turbo spin-echo (SE) MR imaging is valuable for preoperative assessment of T stage and circumferential resection margin in patients with primary rectal cancer. MATERIALS AND METHODS: Local institutional review board approved study and waived informed patient consent. Eighty-three patients with operable primary rectal cancer underwent preoperative MR imaging. Retrospectively, two observers independently scored T2-weighted turbo SE MR images and, in a second reading, T2-weighted images combined with gadolinium-enhanced T1-weighted turbo SE MR images for tumor penetration through rectal wall and tumor extension into mesorectal fascia. A confidence level scoring system was used, and receiver operating characteristic (ROC) curves were generated. Histologic findings were standard of reference. Difference in performance of T2-weighted and combined T2-weighted plus gadolinium-enhanced T1-weighted sequences was analyzed by comparing corresponding areas under ROC curves (A(z)) for each observer. Interobserver agreement was calculated by using linear weighted kappa statistics. RESULTS: Addition of contrast-enhanced T1-weighted to T2-weighted MR imaging did not significantly improve diagnostic accuracy for prediction of tumor penetration through rectal wall (A(z) of T2-weighted vs T2-weighted plus T1-weighted images for observer 1, 0.740 vs 0.764; observer 2, 0.856 vs 0.768) and tumor extension into mesorectal fascia (A(z) for observer 1, 0.962 vs 0.902; observer 2, 0.902 vs 0.911). Diagnostic performance (A(z)) of MR and interobserver agreement were high for prediction of tumor extension into mesorectal fascia (kappa = 0.61, 0.74) but only moderate for penetration through rectal wall (kappa = 0.47, 0.45). CONCLUSION: Gadolinium-enhanced MR sequences did not improve diagnostic accuracy for assessment of tumor penetration through rectal wall and tumor extension into mesorectal fascia.
Original languageEnglish
Pages (from-to)179-188
JournalRadiology
Volume234
Issue number1
DOIs
Publication statusPublished - 1 Jan 2005

Cite this

Vliegen, R. F., Beets, G. L., von Meyenfeldt, M. F., Kessels, A. G., Lemaire, E. E., van Engelshoven, J. M., & Beets-Tan, R. G. H. (2005). Rectal cancer: MR imaging in local staging--is gadolinium-based contrast material helpful? Radiology, 234(1), 179-188. https://doi.org/10.1148/radiol.2341031403