Simultaneous Integrated Boost Preoperative Radiotherapy for Rectum Cancer

Randomized Trial of Preoperative Radiotherapy With an Integrated Simultaneous Boost Compared to Chemoradiotherapy for T3-4 Rectal Cancer

The investigators propose a randomized non-inferiority trial that compares preoperative Fluoro Uracil (FU)-based chemoradiotherapy to radiotherapy with a simultaneous integrated boost. In patients with T3-4 rectal cancer, the latter approach is considered preferential with regard to toxicity and cost. The metabolic response of the tumor, as assessed by 18F-2-Fluoro-2-Deoxyglucose-Positron Emission tomography (18F-FDG PET) or PET-CT, will be used as a surrogate marker of cause specific outcome

Inclusion Criteria:

• histopathologically confirmed rectal adenocarcinoma with an inferior border within 15 cm of the anal verge
• the tumor has to have evidence of T3 or T4 disease on Magnetic Resonance Imaging (MRI) or endoluminal ultrasound

Exclusion Criteria:

• unresectable metastatic disease
• Eastern Cooperative Oncology Group (ECOG) performance status > 3
• patients not deemed fit for radiotherapy, capecitabine or surgery
• pregnant or lactating patients
• women with child bearing potential who lack effective contraception
• patients below 18 years old