RECTAL BOOST Study

Randomized controlled trial in which the effect is investigated of a radiation boost in addition to standard chemoradiation in patients with locally advanced rectal cancer on complete response rate defined as pathological complete response, in those who undergo surgery, or 2-years local recurrence-free survival (2y-LRFS), in those who opted for a wait and see approach. Secondary objectives are adverse events due to chemoradiation (acute, perioperative and late toxicity), tumor response assessed with MRI, the impact of the boost on local and distant recurrence and survival as well as patient-reported quality of life and workability. The need for this comprehensive study is emphasized by the sub-optimal (radiation-) methods, heterogeneity between and poor reporting in the few previous trials in this field.