[Clinical target volume for preoperative radiotherapy of rectal cancers]

The total mesorectal excision allows the marked increase of the local control rate in rectal cancer. Therefore, the mesorectal space is the usual field for the spread of rectal cancer cells. It could therefore be considered as the clinical target volume in the preoperative plan by the radiation oncologist. We propose to identify the mesorectum on anatomical structures of a treatment-position CT scan.