Contact Radiotherapy for Rectal Cancer

Inclusion Criteria: * Adenocarcinoma of the rectum classified as: * cT1-cT3ab, \< 5 cm largest diameter and \< ½ circumference (MRI staging), N0-N1 (\<= 3 nodes \< 8mm diameter), M0 * Performance status (ECOG) 0-1 * Operable patient * Tumor accessible to endocavitary contact X-ray brachytherapy with a distance from the lower tumor border to the anal verge ≤10 cm * 18 years or above * No comorbidity preventing treatment * Patient having read the information note and having signed the informed consent * Follow-up possible Exclusion Criteria: * Inoperable patient * T3cd, T4, T≥ 5cm, Involvement of more than half of the bowel circumference * Distance from the lower tumor border to the anal verge \>10 cm * N2-status at diagnosis or N1 with any node\>= 8 mm diameter * Patient presenting with metastasis at diagnosis (M1) * Previous pelvic irradiation * Tumor with extramural vascular invasion * Poorly differentiated tumor * Simultaneous progressive cancer * Tumor invading external anal sphincter or growth within 1 mm of the levator * Tumor within 1 mm from MRF (mesorectal fascia) * Patient unable to receive CXB or CRT * Any significant concurrent medical illness that in the opinion of the investigator would preclude protocol therapy * Patient with history of poor compliance or current or past psychiatric conditions or severe acute or chronic medical conditions that would interfere with the ability to comply with the study protocol * Concurrent enrolment in another clinical trial using an investigational anti-cancer treatment within 28 days prior to the first dose of study treatment * Total DPD deficiency