Preoperative Gamma-Glutamyltransferase Is Associated with Cancer-Specific Survival and Recurrence-Free Survival of Nonmetastatic Renal Cell Carcinoma with Venous Tumor Thrombus

Abstract

Introduction. To evaluate the prognostic significance of preoperative gamma-glutamyltransferase (GGT) on the subgroup of nonmetastatic renal cell carcinoma (RCC) with venous tumor thrombus. Materials and Methods. We retrospectively reviewed the institutional database and collected the medical data of 156 patients with nonmetastatic RCC with venous tumor thrombus between March 2004 and December 2014. Kaplan-Meier and Cox regression analyses were applied to determine the prognostic factors for cancer-specific survival (CSS) and recurrence-free survival (RFS). Results. The median value and optimal cutoff point of preoperative GGT were 23.0 and 37.5 IU/L, respectively. In the entire cohort, 67 (42.9%) patients experienced disease recurrence, and 46 (29.5%) patients died. Kaplan-Meier analysis revealed that the CSS and RFS rates were lower in patients with preoperative GGT ≥ 37.5 IU/L than in those with preoperative GGT < 37.5 IU/L. Multivariate Cox proportional hazard analysis demonstrated that high preoperative GGT was significantly associated with shorter CSS (hazard ratio [HR]: 2.115; 95% CI: 1.164-3.843; p = 0.014) and RFS (HR: 1.955; 95% CI: 1.166-3.276; p = 0.011), after adjusting other covariates. Conclusions. Preoperative GGT can serve as an independent prognostic biomarker of nonmetastatic RCC patients with venous tumor thrombus. Further prospective study is warranted to confirm our results.

Figure 1

The ROC curve determining the optimal cutoff point of preoperative GGT.

Figure 2

Kaplan-Meier curves of CSS and RFS stratified by preoperative GGT level. (a) Significantly worse CSS in high preoperative GGT group than in low-value group; (b) significantly worse RFS in high preoperative GGT group than in low-value group.