Purpose: To study incidence of local recurrences, postoperative complications and survival, in patients with rectal carcinoma aged 75 years and older, treated with either surgery and pre-operative 5 x 5 Gy radiotherapy or surgery alone. Patients and methods: A random sample of patients aged over 75 years with pT2-T3, N0-2, M0 rectal carcinoma diagnosed between 2002 and 2004 in the Netherlands was included, treated with surgery alone (N = 296) or surgery in combination with pre-operative radiotherapy (N = 346). Information on local recurrent disease, postoperative complications, ECOG-performance score and comorbidity was gathered from the medical files. Results: Local recurrences developed less frequently in patients treated with pre-operative radiotherapy compared to surgery alone (2% vs 6%, p = 0.002). Postoperative complications developed more frequently in irradiated patients (58% vs 42%, p < 0.0001). Especially deep infections (anastomotic leakage, pelvic abscess) were significantly increased in this group (16% vs 10%, p = 0.02). 30-day mortality was equal in both groups (8%). A significant increase in postoperative complication rate and 3 Conclusion: Elderly patients receiving pre-operative radiotherapy show a lower local recurrence rate. However, as incidence rates of local recurrent disease are low and incidence of postoperative complications is increased in irradiated patients, omitting preoperative RT may be suitable in elderly patients with additional risks for complications or early death. (c) 2013 Elsevier Ltd. All rights reserved.