title: First collaborative experience with thulium laser ablation of localized upper urinary tract urothelial tumors using retrograde intra-renal surgery.
abstract: OBJECTIVE
  Thulium laser ablation (TLA) outcomes with blinded performance evaluation after retrograde intra-renal surgical (RIRS) treatment of upper urinary tract transitional cell carcinomas (UUT-TCC).
  
  
  METHODS
  A UUT-TCC patient cohort undergoing RIRS-TLA by an international endoscopic surgical collaboration in a European center (April 2005-July 2009), underwent outcomes evaluation. All 4 surgeons were blinded and independently scored both TLA and Holmium:YAG laser ablation performance aspects annually using a Likert scoring system (0-10).
  
  
  RESULTS
  All patients (n = 59, median age 66 years, 9 with solitary kidney) had complete UUT inspection. Presenting lesion(s) were intra-renal (n = 30, 51%), ureteral (n = 13, 22%), and combined (n = 16, 27%). Single-stage TLA sufficed in 81.4% (tumors < 1.5 cm). Significant recurrence free survival differences occurred according to primary tumor size >/< 1.5 cm and multi-focality, but location made no difference. Median Likert scores were i) fiber-tip stability --5.5/8.75, p = 0.016; ii) reduced bleeding--5/8.5, p = 0.004; iii)fiber-tip precision--5.5/8.5, p = 0.003; iv) mucosal perforation reduction--3.5/7.5, p = 0.001; v) ablation efficiency tumors < 1.5 cm--6/9, p = 0.017; tumors > 1.5 cm--6.75/6.75, p = 1, and vi) overall efficiency--6/7.5, p = 0.09, for Holmium:YAG and TLA, respectively.
  
  
  CONCLUSIONS
  The Thulium laser delivered non-inferior recurrence free survival to RIRS-UUT-TCC Holmium:YAG laser ablation, but better median parameter performance scores in fiber-tip stability, precision, reduced bleeding and mucosal perforation reduction in expert ratings. Despite improved photothermal coagulation, and endo-visualization for tumors < 1.5 cm, both ablation and overall efficiency remained challenging for larger tumors with both existing laser technologies.
authors.affiliation: Department of Urology, Cristo Re Hospital, Rome, Italy. defidio@tin.it
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Defidio
authors.forename: Mauro
authors.initials: M
authors.lastname: De Dominicis
authors.forename: Luca
authors.initials: L
authors.lastname: Di Gianfrancesco
authors.forename: Gerhard
authors.initials: G
authors.lastname: Fuchs
authors.forename: Anup
authors.initials: A
authors.lastname: Patel
mesh_terms: D000368:Aged; D005260:Female; D006695:Holmium; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery; D053685:Laser Therapy / Q000379:methods; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D013932:Thulium; D016896:Treatment Outcome; D014516:Ureteral Neoplasms / Q000473:pathology / Q000601:surgery; D014571:Urologic Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods*
chemical_list: D013932:Thulium; D006695:Holmium