ABSTRACTIntroduction: Multimodality treatment of patients with locally advanced rectal cancer (LARC) has significantly improved local disease control, however the unaltered overall survival (OS) implicates an inability to further control micrometastases, providing rationale for intensified systemic treatment.A systematic review was conducted to evaluate the efficacy and toxicity of adding oxaliplatin to a fluoropyrimidine (intervention) compared with fluoropyrimidine alone (control) in the treatment of LARC.Methods: We searched CENTRAL, Medline Ovid, PubMed and EMBASE databases. Randomised trials comparing the intervention and control delivered either pre- or post-operatively were included.Results: Seven trials involving 4444 patients were identified; five studies evaluated the intervention vs control preoperatively; one study peri-operatively; and one, post-operatively. There was no significant difference in OS with oxaliplatin addition, HR 0.89, 95% CI, 0.75 to 1.06. There was however an improvement in disease free survival, 3-year local and distant recurrence rates (RR) favouring oxaliplatin. Preoperative oxaliplatin improved pathological complete response (pCR), but with a greater toxicity and reduced compliance with radiation.Conclusion: There is no OS benefit with oxaliplatin, despite improved pCR, local and distant RR. Before drawing definitive conclusions, longer follow-up in included trials and availability of published data from other eligible studies, including the induction setting, are needed.