title: The method of GFR determination impacts the estimation of cisplatin eligibility in patients with advanced urothelial cancer.
abstract: OBJECTIVE
  To determine GFR with different methods in patients with first-line chemotherapy for advanced urothelial cancer (UC) and to evaluate the impact of these methods on the estimation of cisplatin eligibility.
  
  
  METHODS
  A database was built retrospectively containing all patients receiving first-line chemotherapy for UC between 2001 and 2012 in one German high-volume center. GFR was calculated with the methods by Cockcroft-Gault (CG), MDRD and CKD-EPI. Measurements of creatinine clearance with timed urine collections were registered.
  
  
  RESULTS
  A total of 166 patients were included. All methods of renal function determination yielded consistent results in terms of cisplatin eligibility for 134 patients (80.7 %) and disagreeing results for 32 patients (19.3 %). Twenty-two of these 32 patients with borderline GFR received cisplatin-based chemotherapy. Fifteen of these 22 patients completed at least three cycles. The mean GFR in the mentioned 32 patients was 51.3, 56.2 and 54.2 ml/min with the method by CG, MDRD and CKD-EPI. Three, ten and four patients were estimated cisplatin-eligible with either method. There was a good correlation between MDRD and CKD-EPI (r (2) = 0.92). CG tended to underestimate GFR compared to both MDRD and CKD-EPI. Measurements of creatinine clearance showed a wide distribution in comparison with MDRD (r (2) = 0.002).
  
  
  CONCLUSIONS
  The method used to determine GFR influences the estimation of cisplatin eligibility in a subset of UC patients. MDRD and CKD-EPI formulas seem most valuable, while CG tends to underestimate renal function. Using a strict cutoff of 60 ml/min may unnecessarily preclude cisplatin in some patients.
authors.affiliation: Department of Urology, Klinikum rechts der Isar, Urologische Klinik der Technischen Universität München, Technische Universität München, Ismaningerstraße 22, 81675, Munich, Germany, t.horn@lrz.tum.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Horn
authors.forename: Barbara
authors.initials: B
authors.lastname: Ladwein
authors.forename: Tobias
authors.initials: T
authors.lastname: Maurer
authors.forename: Jutta
authors.initials: J
authors.lastname: Redlin
authors.forename: Anna Katharina
authors.initials: AK
authors.lastname: Seitz
authors.forename: Jürgen E
authors.initials: JE
authors.lastname: Gschwend
authors.forename: Margitta
authors.initials: M
authors.lastname: Retz
authors.forename: Hubert R
authors.initials: HR
authors.lastname: Kübler
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D016190:Carboplatin / Q000008:administration & dosage; D002295:Carcinoma, Transitional Cell / Q000188:drug therapy* / Q000473:pathology; D002945:Cisplatin / Q000008:administration & dosage; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood / Q000652:urine; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D016014:Linear Models; D008297:Male; D018579:Patient Selection; D051437:Renal Insufficiency / Q000175:diagnosis* / Q000517:prevention & control; D012189:Retrospective Studies; D000093542:Gemcitabine
chemical_list: D003841:Deoxycytidine; D003404:Creatinine; D016190:Carboplatin; D002945:Cisplatin; D000093542:Gemcitabine