Abstract
BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) caused by chronic hepatitis B virus (HBV) infection has become prominent. Prospectively stratifying postoperative risk factors is a challenging task. METHODS: We retrospectively assessed the relationship between serum gamma-glutamyl transpeptidase (GGT) concentration and postoperative outcomes in 107 subjects with HBV-associated ICC. Cox proportionate hazard models and subgroup analyses were used to test the hypothesis with adjustment for potential confounders. RESULTS: Serum GGT concentration was negatively correlated with postoperative outcomes. For a 1-standard deviation (per-SD) (117 µ/L) increase of serum GGT concentration, the relative risk (RR) for overall survival (OS) and time to recurrence (TTR) were 1.72 [95% confidence interval (CI), 1.37 to 2.16] and 1.53 (95% CI, 1.22 to 1.91), respectively. In addition, the RRs of middle and top tertiles of GGT for death were 1.81 (95% CI, 0.98 to 3.32) and 3.56 (95% CI, 1.97 to 6.42), respectively (P for trend <0.001). Similarly, the RRs for recurrence of the corresponding tertiles were 1.70 (95% CI, 0.93 to 3.10) and 3.27 (95% CI, 1.77 to 6.06), respectively (P for trend =0.002). In our study, the negative correlation between serum GGT levels and OS did not differ significantly between groups stratified by age, sex, HBV DNA level, carbohydrate antigen 19-9 (CA19-9) level and liver resection type (all P for interaction >0.05); however, there was a significant interactive effect of serum GGT and adjuvant chemotherapy on OS (RR =0.64 vs. 1.77, P for interaction =0.04). CONCLUSIONS: High serum GGT concentration is associated with an increased risk of postoperative death and tumor recurrence in patients with HBV-associated ICC. However, this relationship became less significant with the implementation of adjuvant chemotherapy.