Background and aims: This study was conducted to clarify the effects of age on human liver regeneration.
Patients and methods: Thirty major hepatectomies, equal to or more than two segmentectomies for hepatocellular carcinoma, were performed. Ages ranged from 37 to 85 years and five octogenarians were included. The early regenerative index was defined: (liver volume after 7 days after hepatectomy - estimated remnant liver volume before hepatectomy)/estimated remnant liver volume, using three-dimensional computed tomographic volumetry. Farnesoid X receptor and forkhead box m1 expression in the liver, which has been reported to age-related decrease of liver regeneration in animal model, were examined using real-time polymerase chain reaction. The patients were divided into two groups: low early regenerative index (n = 15), early regenerative index less than 55% and high early regenerative index (n = 15), early regenerative index equal to or more than 55%.
Results: The mean early regenerative index was 57%. Age (R (2) = 0.274, P = 0.003) and estimated blood loss (R (2) = 0.134, P = 0.0466) were inversely correlated with the early regenerative index, and the expression of farnesoid X receptor and forkhead box m1 was not. The incidence of post-hepatectomy liver failure in the low early regenerative index group was higher than that in the high early regenerative index group (P = 0.0421).
Conclusions: Age and intraoperative blood loss are inversely correlated with early liver regeneration in humans. In elderly patients, massive blood loss should be avoided in view of liver regeneration.
Keywords: Liver regeneration; age; early regenerative index; hepatic resection; human.