The association between preoperative serum interleukin-6 levels and postoperative prognosis in patients with T2 gallbladder cancer.

BACKGROUND

Interleukin-6 (IL-6) is closely associated with tumor progression. Whether it can predict postoperative prognosis of patients with T2 gallbladder cancer (GBC) remains controversial.

METHODS

We retrospectively collected the medical records of 125 patients with T2 GBC. Then, we analyzed the association between preoperative serum IL-6 levels and postoperative survival by multivariate Cox analyses and Kaplan-Meier curves in exploratory subgroups.

RESULTS

Predictive effects of serum IL-6 levels on overall survival were similar across most of the evaluated subgroups, except in different tumor location subgroups. The independent odds ratio (OR) of serum IL-6 levels was 2.57 (95%CI 1.73-3.82) in the hepatic side subgroup, while it was 1.15 (95%CI 0.68-1.93) in the peritoneal side subgroup (P = 0.014 for interaction). When we categorized serum IL-6 levels by median value (4.2 pg/mL), the 5-year survival rate of patients with high serum IL-6 levels was significantly higher in the hepatic side subgroup (58.5% vs 14.8%, P < 0.001), but no such difference was found in the peritoneal side subgroup (62.2% vs 67.6%, P = 0.722).

CONCLUSIONS

Preoperative serum IL-6 is significantly associated with prognostic implications in patients with hepatic side T2 GBC, not in those with peritoneal side tumors.