Effects of oral 5-fluorouracil drugs on hepatic fat content in patients with colon cancer

Abstract

Rationale and objectives: The association between hepatic steatosis and oral 5-fluorouracil (5-FU) agents is clinically recognized but has not been systematically studied. The aim of this study was to determine the effects of 5-FU on hepatic fat content in patients undergoing oral 5-FU therapy and to compare the effects in three subgroups of 5-FU drugs.

Materials and methods: Fifty-one patients with postoperative colon cancer (mean 61.1 years) were retrospectively studied. Forty-three patients were given adjuvant oral 5-FU therapy for a mean 3.3 years (5-FU group), and eight patients were not (control group). All patients underwent preoperative and postoperative abdominal computed tomography (CT) studies. The liver/spleen ratio was calculated from the CT attenuation values for the liver and spleen. We also compared the effects on hepatic appearance under CT of three 5-FU drugs: fluorouracil (n = 13), doxifluridine (n = 14), or UFT (a mixture of tegafur and uracil; n = 9).

Results: In the 5-FU group, the mean CT values for the liver were significantly reduced relative to values before therapy (P < .01) and to those of the control group (P < .0001). Fifteen of 43 patients (34.9%) developed steatosis. Of the three 5-FU drugs, fluorouracil and doxifluridine caused a significant decrease in hepatic CT values.

Conclusion: 5-FU caused a significant decrease in CT attenuation, indicating an increase in hepatic fat content, and was associated with very frequent hepatic steatosis. UFT seemed less likely to cause hepatic fatty infiltration. CT examination was useful for early detection of drug-induced side effects on liver even before lab abnormality or clinical manifestation is observed.