title: Preoperative serum-gamma-glutamyltransferase (GGT) does not represent an independent prognostic factor in a European cohort of patients with non-metastatic renal cell carcinoma.
abstract: OBJECTIVE
  Increasing evidence suggests that the serum-gamma-glutamyltransferase (GGT) might correlate with tumour development and growth rates in various human cancer types. Thus, we decided to investigate the potential prognostic impact of the preoperatively assessed serum-GGT in a European cohort of patients with non-metastatic renal cell carcinoma (RCC).
  
  
  METHODS
  Clinicopathological data from 700 consecutive patients with non-metastatic RCC, operated between 2000 and 2010 at a single tertiary academic centre, were evaluated retrospectively. Preoperative serum-GGT was assessed 1 day before surgery. Patients were categorised using a serum-GGT cut-off value of 40 U/L according to a calculation by receiver operating curve analysis. Patients' cancer-specific survival (CSS), metastasis-free survival (MFS), as well as overall survival (OS) were assessed using the Kaplan-Meier method and Cox proportional models.
  
  
  RESULTS
  In univariate analysis, an elevated preoperative serum-GGT level (<40 U/L vs ≥40 U/L) was statistically significantly associated with a shorter MFS (HR=1.517, 95% CI 1.047 to 2.197, p=0.027). In multivariate analyses, pathological T-Stage (pT-1 vs pT-2-4, HR=2.065, 95% CI 1.665 to 2.560), tumour grade (G-1+G-2 vs G-3+G-4, HR=1.671, 95% CI 1.261 to 2.213), as well as the presence of histological tumour necrosis (No vs Yes, HR=2.031, 95% CI 1.355 to 3.046) were independent predictors of MFS in patients with RCC, whereas the preoperative serum-GGT failed to reach independent predictor status (<40 U/L vs ≥40 U/L, HR=1.156, 95% CI 0.791 to 1.690). No prognostic role for GGT in OS or CSS could be identified.
  
  
  CONCLUSIONS
  In the cohort studied, patients with an elevated (≥40 U/L) preoperative serum-GGT had a subsequently shorter MFS only in univariate analysis. In contrast to previous studies, our data failed to demonstrate preoperatively assessed serum-GGT as an independent prognostic factor in patients with non-metastatic RCC.
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Orietta
authors: O
authors: Dalpiaz
authors: Division of Oncology, Department of Internal Medicine, Medical University of Graz, Graz, Austria Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
authors: Martin
authors: M
authors: Pichler
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Edvin
authors: E
authors: Mrsic
authors: Division of Oncology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors: Daniel
authors: D
authors: Reitz
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Daniel
authors: D
authors: Krieger
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Luca
authors: L
authors: Venturino
authors: Division of Oncology, Department of Internal Medicine, Medical University of Graz, Graz, Austria.
authors: Angelika
authors: A
authors: Bezan
authors: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria.
authors: Tatjana
authors: T
authors: Stojakovic
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Karl
authors: K
authors: Pummer
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Richard
authors: R
authors: Zigeuner
authors: Department of Urology, Medical University of Graz, Graz, Austria.
authors: Georg C
authors: GC
authors: Hutterer
mesh_terms: D000368:Aged; D019540:Area Under Curve; D001317:Austria / Q000453:epidemiology; D014408:Biomarkers, Tumor / Q000097:blood*; D002292:Carcinoma, Renal Cell / Q000097:blood / Q000201:enzymology* / Q000208:ethnology / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000097:blood / Q000201:enzymology* / Q000208:ethnology / Q000401:mortality / Q000473:pathology; D008297:Male; D015999:Multivariate Analysis; D009336:Necrosis; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D015854:Up-Regulation; D044465:White People; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; D005723:gamma-Glutamyltransferase; C554782:gamma-glutamyltransferase, human
keywords: RENAL CANCER; TUMOUR MARKERS; UROPATHOLOGY