Objectives The current standard treatment for patients with rectal cancer stage II–III is neoadjuvant chemoradiotherapy followed by surgery. Neoadjuvant chemoradiotherapy can be performed with 5-fluorouracil (5-FU) or capecitabine (CPC) considered to be equivalent therapies. Medication cost is higher for CPC than for 5-FU, however, the administration of continuous 5-FU intravenous infusion is related to other costs such as those associated with outpatient facilities or central venous catheter insertion.

Methods This retrospective study analysed the direct sanitary costs associated with the treatments and their complications from a hospital perspective. Costs in patients treated with 5-FU or CPC were measured between January 2010 and July 2018 at Mataró Hospital. The aim of this study was to perform a cost-minimisation analysis between the two treatments. We aimed to assess the cost associated with the complications related to each drug and the economic impact of applying the most efficient option.

Results Ninety-eight patients were analysed: 32 were treated with CPC and 66 with 5-FU. Treatment cost was significantly higher for 5-FU than for CPC (2560.86±99.17 and 563.10±9.52 respectively, P=0.0001). No significant differences were found in the costs associated with treatment complications between groups (148.21±934.91 and 41.41±102.50 euros respectively, P=0.322).

Conclusions Considering the clinical equivalence shown in the available trials and previous reviews, the most efficient treatment is neoadjuvant chemoradiotherapy with CPC. Complications associated with the treatments did not significantly modify these results. Other studies gave similar results both in the neoadjuvant and adjuvant context, reaffirmed in this study.