Hypertriglyceridemia induced by S-1: A novel case report and review of the literature.

S-1 administration induced hypertriglyceridemia owing to the elevated serum triglyceride; however, a contrasting result was observed in the S-1 withdrawal period and during the S-1-cessation cycle. Since dietary intake was poorer during the S-1 administration period, it is considered that S-1 might have disturbed lipid metabolism. Further, we know that capecitabine, which is a prodrug of fluorouracil, also induces hypertriglyceridemia. As the end product of these medicines is fluorouracil, the presence of fluorouracil or its metabolizing enzymes, the genetic background of the patient might have affected the results. We have to be aware of the risk of asymptomatic and temporal occurrence of hypertriglyceridemia by S-1 administration for the early detection with appropriate pre-emptive treatment.