Prognostic significance of serum γ-glutamyltransferase in patients with advanced urothelial carcinoma.

OBJECTIVES

Serum γ-glutamyltransferase (GGT) is reportedly associated with prognosis in patients with various malignancies. However, the prognostic role of GGT is unknown among patients with advanced urothelial carcinoma (aUC). This study was designed to examine the prognostic role of serum GGT in patients with aUC.

MATERIALS AND METHODS

Charts of 125 consecutive aUC patients (inoperable cT4 and/or metastasis to lymph nodes/distant organs) managed at a single cancer center between 2004 and 2016 were retrospectively reviewed. Variables collected included age, sex, body mass index, Karnofsky performance status, primary site, clinical tumor stage, lymph node/visceral metastasis, hepatic comorbidities, the presence of curative treatment before the diagnosis of aUC, white blood cell count, neutrophil-to-lymphocyte ratio, hemoglobin, albumin, lactate dehydrogenase, alkaline phosphatase, GGT, C-reactive protein, and treatments given after the diagnosis of aUC. Associations of variables with overall survival (OS) were analyzed using the Cox proportional hazard model.

RESULTS

Serum GGT was elevated (≥60 U/l) at the diagnosis of aUC in 16 patients (13%). During follow-up period (median 12.1 months), 101 patients died (2-year OS rate, 32%). Patients with elevated GGT at the diagnosis of aUC had a significantly poorer prognosis than those with normal GGT with respective 2-year OS rates of 0% and 37% (P < 0.001). On multivariate analysis, elevated GGT was a significant and independent risk factor for shorter OS (hazard ratio, HR = 2.97; P < 0.001) as were poorer Karnofsky performance status (HR = 3.47; P < 0.001), elevated lactate dehydrogenase (HR = 1.86; P = 0.033), advanced age (HR = 1.82; P = 0.013), elevated neutrophil-to-lymphocyte ratio (HR = 1.80; P = 0.015), elevated C-reactive protein (HR = 1.73; P = 0.018), the absence of systemic chemotherapy (HR = 1.71; P = 0.035), and primary site of upper urinary tract (HR = 1.71; P = 0.014) in descending order by HR. The prognostic significance of elevated GGT was also observed in a subset of 101 patients who had been diagnosed with aUC at their first presentation.

CONCLUSION

The present study for the first time demonstrated that elevated serum GGT was an independent adverse prognostic factor in aUC patients.