Role of dynamic perfusion magnetic resonance imaging in patients with local advanced rectal cancer

Figure 1 Staging dynamic-contrast enhanced magnetic resonance imaging (MR1) performed with 3D-T1 THRIVE images; the corresponding color map and time-intensity curves. A: The T1 THRIVE image shows an example of freehand delineation of the tumor during an MRI study performed for staging purpose (the tumor was a T3N0); B: The related color map was created by the software, and the delineation of the tumor on the T1 THRIVE was automatically reported also on the color map; C: The time-intensity curves table show the results of the delineations on the tumor (which correspond to the highest curves) and on the healthy rectal wall.

Figure 2 Magnetic resonance imaging study performed for rectal cancer restaging after chemo-radiotherapy with standard T2 weighted sequences and dynamic-contrast enhanced magnetic resonance imaging with 3D-T1 THRIVE images; the corresponding color map and time-intensity curves. A and B: The T2 weighted sequences show a slight thickness in the rectal wall on the left side (from 2 to 5 o'clock) that corresponds to the residual tumor bed; C: The dynamic-contrast enhanced-study show the delineation of the tumor and the time-intensity curves show, with similar curves for the tumor and the healthy rectal wall; D: At histology this patient was classified as a tumor regression grade 1.

Figure 3 Differences in terms of perfusion parameters between responders and non-responders, in the tumor tissue and the healthy rectal wall, determines through a dynamic contrast enhanced magnetic resonance imaging study for rectal cancer restaging after chemo-radiotherapy. CRT: Chemo-radiotherapy.

Figure 4 Correlation between the relative arterial enhancement and the relative venous enhancement at MR2.

Figure 5 Dynamic-contrast enhanced magnetic resonance imaging study performed for restaging of rectal cancer after chemoradiation therapy with 3D-T1 THRIVE and T2 weighted sequences; the corresponding color map and time-intensity curves. A: The T2 weighted sequences show a slightly hypointense thickness in the rectal wall on the anterior side (from 11 to 2 o’clock) that corresponds to the fibrotic residual tumor bed; B: The dynamic-contrast enhanced-study performed after chemo-radiotherapy show that on the T1 THRIVE sequence some tissue thickness is present (12 o'clock) and the corresponding time-intensity curves show a significant difference between the healthy rectal wall and the tumor; C: At histology was classified as a tumor regression grade 3.