The purpose of this study was to present the Lyon experience using radiotherapy alone or with surgery, with intent to cure rectal cancer and to avoid rectal amputation. Two groups of patients were treated between 1980 and 1996: Group I with radiotherapy alone with contact x-ray for T1 N0 (101 patients) or with a combination of external beam radiation therapy (EBRT), contact x-ray and 192 iridium implant in inoperable T2-3 N0-1 patients (43 patients); Group II with preoperative EBRT either as a pilot study (158 patients) or in a randomized trial (210 patients). With contact x-ray alone it was possible to control T1 N0 in 90% of cases, and with the combined approach 70% of the inoperable patients were controlled. In Group II, anterior resection was performed in 60% to 70% of the patients. Local recurrence was seen in 11% of cases. Surgery is the basic treatment used for rectal cancer but radiotherapy is playing an increasing role in the conservative treatment of this cancer.