64Cu-ATSM PET/CT in Rectum Cancer (TEP 64Cu-ATSM-Rectum)

Inclusion Criteria:

• Histologically confirmed rectum adenocarcinoma
• Locally advanced, non metastatic disease, with or without locoregional lymph nodeinvolvement (greater than or equal to T3 +/- N), first-line therapy
• 18 Years and older
• Performance Status equal to 0 or 1
• Fertile patients must use effective contraception
• Hemoglobin greater than 9g/dl, neutrophils greater than 1 500/mm3, platelets greaterthan 100 000/mm3
• Creatinine clearance greater than or equal to 50ml/min
• Plan to receive treatment with concurrent chemotherapy and radiation therapy followedby surgery
• Totality of the tumor included in the radiotherapy field
• Written informed consent
• Patient must be affiliated to a Social Health Insurance

Exclusion Criteria:

• metastatic disease
• Patient contraindicated for capecitabine or 5FU (5-Fluoro-Uracile) derivatives (history of severe and unexpected reactions to fluoropyrimidine-containing therapy,known hypersensitivity to 5FU, to any of the excipients, or known total DPD (dihydropyrimidine déshydrogénase) deficiency)
• Known Contraindication to perform MRI
• Previous treatment with pelvic radiotherapy
• Chronic inflammatory bowel disease, malabsorption, lack of colonic integrity
• Diarrhea grade greater than 2
• Contraindication to surgery
• Bilateral total hip prosthesis
• Other malignancy treated within the last 5 years (except non-melanoma skin cancer orin situ carcinoma of the cervix)
• Pregnant or nursing patient
• Individual deprived of liberty or placed under the authority of a tutor
• Impossibility to submit to the medical follow-up of this clinical trial forgeographical, social or psychological reasons
• Agitation; impossibility of lying motionless for at least 1 hour, or knownclaustrophobia