Fluoropyrimidine-induced hand-foot syndrome and cardiotoxicity: recommendations for the use of the oral fluoropyrimidine S-1 in metastatic colorectal cancer

•HFS is a common toxicity of FP treatment that requires dose reductions or treatment interruptions.•CVT occurs less frequently but prevents the safe continuation of FP treatment.•S-1 is approved by European Medicines Agency for CRC patients who cannot continue FP treatment because of these toxicities.•Recommendations for use of S-1 in clinical practice are provided.