Efficacy of Neoadjuvant Folfirinox Regimen in Patients With Resectable Locally Advanced Rectal Cancer

Inclusion Criteria: * Histologically proven rectal adenocarcinoma * Stages cT3 with risk of local recurrence or cT4, M0 and for which a multidisciplinary meeting recommend preoperative CRT * Resectable tumor, or considered as potentially resectable after CRT * No distant metastases * Patient eligible for surgery * Patient aged from 18 to 75 years * World Health Organization (WHO)/Eastern Cooperative Oncology Group (ECOG) performance status 0/2. * No heart failure or coronary heart disease symptoms (even controlled). * No peripheral neuropathy \> grade 1 * No prior radiotherapy of the pelvis for any reason and no previous CT * No major comorbidity that may preclude the delivery of treatment and no active infection (HIV or chronic hepatitis B or C). * Adequate contraception in fertile patients. * Adequate hematologic function * Adequate hepatic function * Signed written informed consent Exclusion Criteria: * Metastatic disease * Unresectable rectal cancer, including prostatic involvement or extension to pelvic floor muscles * Contraindication to 5-FU, or to oxaliplatin or to irinotecan, including Gilbert disease or genotype UGT1A1 * Medical history of chronic diarrhea or inflammatory disease of the colon or rectum * Medical history of angina pectoris or myocardial infarction * Progressive active infection or any other severe medical condition that could jeopardize treatment administration * Other concomitant cancer, or medical history of cancer other than treated in situ cervical carcinoma or basocellular carcinoma or spinocellular carcinoma * Patient included in another clinical trial testing an investigational agent. * Pregnant or breast-feeding woman. * Persons deprived of liberty or under guardianship or incapable of giving consent * Any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol or follow-up schedule.