Diffusion-weighted magnetic resonance imaging for predicting the response of rectal cancer to neoadjuvant concurrent chemoradiation

Figure 1 Sample T2-weighted and diffusion-weighted images from a patient with locally advanced rectal cancer prior to treatment. A: T2-weighted transaxial image through the pelvis prior to treatment; B: Corresponding apparent diffusion coefficient map of the patient obtained from the diffusion-weighted images. A region of interest was drawn around the tumor.

Figure 2 Apparent diffusion coefficient maps of one patient obtained at constant intervals once weekly during the course of neoadjuvant treatment from the diffusion-weighted images. A-E: Axial apparent diffusion coefficient maps obtained during treatment (weeks 1-5). A region of interest was drawn around the tumor.

Figure 3 Mean tumor apparent diffusion coefficient values in patients at six measurement points. A: With and without T downstaging; B: With good regressin and poor regression. Cycle: Outlier; Star: Extreme value.