PT  - JOURNAL ARTICLE
AU  - K.W. Yeom
AU  - R.M. Lober
AU  - B.C. Mobley
AU  - G. Harsh
AU  - H. Vogel
AU  - R. Allagio
AU  - M. Pearson
AU  - M.S.B. Edwards
AU  - N.J. Fischbein
TI  - Diffusion-Weighted MRI: Distinction of Skull Base Chordoma From Chondrosarcoma
AID  - 10.3174/ajnr.A3333
DP  - 2012 Nov 01
TA  - American Journal of Neuroradiology
4099  - http://www.ajnr.org/content/early/2012/11/01/ajnr.A3333.short
4100  - http://www.ajnr.org/content/early/2012/11/01/ajnr.A3333.full
AB  - BACKGROUND AND PURPOSE: Chordoma and chondrosarcoma of the skull base are rare tumors with overlapping presentations and anatomic imaging features but different prognoses. We hypothesized that these tumors might be distinguished by using diffusion-weighted MR imaging. MATERIALS AND METHODS: We retrospectively reviewed 19 patients with pathologically confirmed chordoma or chondrosarcoma who underwent both conventional and diffusion-weighted MR imaging. Differences in distributions of ADC were assessed by the Kruskal-Wallis test. Associations between histopathologic diagnosis and conventional MR imaging features (T2 signal intensity, contrast enhancement, and tumor location) were assessed with the Fisher exact test. RESULTS: Chondrosarcoma was associated with the highest mean ADC value (2051 ± 261 × 10-6 mm2/s) and was significantly different from classic chordoma (1474 ± 117 × 10-6 mm2/s) and poorly differentiated chordoma (875 ± 100 × 10-6 mm2/s) (P < .001). Poorly differentiated chordoma was characterized by low T2 signal intensity (P = .001), but other conventional MR imaging features of enhancement and/or lesion location did not reliably distinguish these tumor types. CONCLUSIONS: Diffusion-weighted MR imaging may be useful in assessing clival tumors, particularly in differentiating chordoma from chondrosarcoma. A prospective study of a larger cohort will be required to determine the value of ADC in predicting histopathologic diagnosis. Abbreviations PDpoorly differentiated