What Are the Present Recommendations for Short-Course Preoperative Radiotherapy (RT) and Delayed Surgery?

Short-course radiotherapy (RT) to 5 × 5 Gy with immediate surgery is an established treatment to lower local failure rates in many patients with primary rectal cancer. If surgery is delayed for 4–8 weeks, downstaging/downsizing is frequently seen and a pathological complete remission is seen in 10–15% of the patients. Previously non-resectable tumors have then frequently become resectable with long-term cure in a proportion of the patients. It has very low acute (and late) toxicity and is an alternative in elderly patients if comorbidity prevents chemoradiotherapy (CRT). It has been explored in randomized trials also in younger and fit patients and may become an alternative to short-course with immediate surgery and to CRT, both because of less acute toxicity and convenience with similar efficacy. The latter remains to be established.