PET-CT examination can be performed immediately after chemotherapy as the baseline film for future review. The regular review after chemotherapy for rectal cancer is CT and CEA of chest, abdomen and pelvis every three months in the first year, CT and CEA of chest, abdomen and pelvis every six months in the second year, CT and CEA of chest, abdomen and pelvis every year from the third to the fifth year, and CT and ECA of chest, abdomen and pelvis every two years after five years. There is no requirement for PET-CT, but patients with good conditions can have their PET-CT reviewed once a year, and of course, they can have all their CT reviews replaced with PET-CT.