Sasaki T, et al. - Researchers investigated the prognostic role of the apparent diffusion coefficient (ADC) in chordomas. For this investigation, 16 subjects with residual or recurrent chordoma were split up postoperatively into those with an aggressive tumor, characterized as a growing tumor having a doubling time of < 1 year, and those with a nonaggressive tumor on follow-up MR images. Using a Kaplan-Meier curve with a log-rank test, the prognostic role of ADC was evaluated. With significantly lower mean ADC being found in the aggressive tumor group vs the nonaggressive tumor group, results of this study suggested that lower ADC values could predict tumor progression in postoperative chordomas.