 Phase II, nonrandomized single-arm trial of preoperative treatment with mFOLFOX-6 and panitumumab in an enriched population of patients with rectal adenocarcinoma of intermediate risk, screened by MRI, without mutations in KRAS, BRAF, NRAS and PI3K. All patients enrolled in the study will receive 12 weeks of the investigational product mFOLFOX-6 with panitumumab every 14 days for six cycles, unless unacceptable toxicity occurs or progression is detected. After this treatment, response will be evaluated by diffusion-weighted MRI and endoscopy. In the absence of disease progression, patients eligible for R0 resection will undergo total mesorectal excision TME. After surgery, patients will receive mFOLFOX6 x 6 cycles. In the case of intolerance to FOLFOX-panitumumab, disease progression or ineligibility for R0 resection, patients will receive chemoradiotherapy with capecitabine 825 mgm2 every 12 hours concomitantly with radiotherapy RT with a total dose of 50.4 Gy. At the end of this treatment, patients will undergo TME between 6 and 8 weeks after the end of chemoradiotherapy. If a patient withdraws consent and refuses to continue treatment, the patient will be followed up for 24 months, from the enrollment of the last patient in the trial, or until progression occurs, in order to assess disease-free survival. If a patient withdraws consent and refuses to continue participating in the study, follow-up evaluations must be discontinued. 