title: Analysis of the impact of adherent perirenal fat on peri-operative outcomes of robotic partial nephrectomy.
abstract: BACKGROUND
  Adherent perirenal fat (APF) can be defined as inflammatory fat sticking to renal parenchyma, whose dissection is difficult and makes it troublesome to expose the tumour. Our objective was to evaluate the impact of APF on the technical difficulty of robot-assisted partial nephrectomy (RPN).
  
  
  METHODS
  We analysed data of 202 patients who underwent RPN for a small renal tumour. Patients were divided into two groups according to the presence of APF. Peri-operative data were compared between the two groups. Predictors of APF were evaluated by univariate and multivariate analysis. The validity of the MAP score (radiological scoring system) was also assessed.
  
  
  RESULTS
  APF was observed in 80 patients (39.6 %). Tumour complexity and surgeon's experience were similar between both groups. Operative time was 40 min longer in the APF group (188.5 vs. 147.9 min, p < 0.0001). Blood loss was twice higher, and transfusions were more common in the APF group (694 vs. 330 ml, p < 0.0001 and 19 vs. 5.8 %, p = 0.003, respectively). APF was associated with an increased risk of conversion to open surgery (11.2 vs. 0 %, p = 0.0002) or radical nephrectomy (6.2 vs. 0.8 %, p = 0.03). In multivariate analysis, male gender (OR 13.2, p < 0.0001), obesity (OR 1.2, p = 0.007), hypertension (OR 3.7, p = 0.02), and MAP score (OR 3.3; p < 0.0001) were significant predictors of APF.
  
  
  CONCLUSIONS
  During RPN, APF is associated with increased bleeding and a higher risk of conversion to open surgery and to radical nephrectomy. Male gender, hypertension, obesity, and MAP score are predictors of APF.
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France. zineddine.khene@gmail.com.
authors: Zine-Eddine
authors: ZE
authors: Khene
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France.
authors: Benoit
authors: B
authors: Peyronnet
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France.
authors: Romain
authors: R
authors: Mathieu
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France.
authors: Tarek
authors: T
authors: Fardoun
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France.
authors: Grégory
authors: G
authors: Verhoest
authors: Department of Urology, Rennes University Hospital, 2, rue Henri Le Guilloux, 35033, Rennes Cedex, France.
authors: Karim
authors: K
authors: Bensalah
mesh_terms: D000273:Adipose Tissue / Q000473:pathology* / Q000601:surgery; D015992:Body Mass Index; D002292:Carcinoma, Renal Cell / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000473:pathology / Q000601:surgery; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D012371:Robotics
keywords: Adherent; Complications; Fat; Partial nephrectomy; Robotic surgery