[Radiotherapy of rectal cancer]

The hallmark of successful management of rectal cancer is complete resection. In early stage disease, removal of all of the perirectal soft tissue structures, the mesorectum can be achieved with a total mesorectal excision (TME), resulting in high rates of local control. In cases of cancer extending through the muscularis propria or in case of lymphonodal involvement, additional radiation therapy can further substantially reduce the risk of pelvic recurrences. The combined treatment with radiotherapy followed by surgery is more effective than postoperative radiotherapy. Preoperative radiotherapy increases the survival rate of rectal cancer patients using limited doses of ionizing radiation and customized treatment volumes. The introduction of functional imaging with positron-emission tomography integrated in a conventional computer-associated tomography system (PET/CT) can be used for radiation treatment planning enhancing treatment precision and standards. The PET/imaging can be reliably used therapy for the purpose of combined staging and treatment volume assessment.