title: Volumetric gain of the liver after major hepatectomy in obese patients: a case-matched study in 84 patients.
abstract: OBJECTIVE
  The objective was to determine the liver volumetric recovering capacity and postoperative course after major hepatectomy in obese patients through a case-matched study.
  
  
  BACKGROUND
  In literature, the impact of obesity on liver recovering has been analyzed only indirectly in terms of morbimortality but never through volumetric assessment.
  
  
  METHODS
  Between 2005 and 2011, 42 patients with body mass index (BMI) 30 or higher (Ob group) underwent major hepatectomy and were matched with 42 patients with BMI 25 or lower (NonOb group) on the magnitude of resection (number of resected segments ±1, remnant liver volume to total liver volume, RLV/TLV, ±5%). The RLV was measured on computed tomographic slices preoperatively and postoperatively at 1 month (RLV-1M) for all patients and within 3 to 12 months in 42 paired patients (median = 6 months, RLV-6M). Considering hepatomegaly in Ob group, RLV was also normalized to body weight (RLVBWR). The liver volumetric gain was expressed as a relative increase [(RLV-1M - RLV)/RLV] or increase in RLVBWR.
  
  
  RESULTS
  The Ob and NonOb groups were comparable regarding clinicopathological data, except for arterial hypertension (48% vs 19%; P = 0.005), mean steatosis (24% vs 10%; P = 0.03), and fibrosis incidence (33% vs 10%; P = 0.008). Ob group showed longer operative time and higher blood losses. There were no intergroup differences in liver failure (both 7.1%) and 90-day morbimortality. Despite comparable RLV/TLV (38.1% vs 37.7%; P = 0.13), the relative liver volumetric gain at 1 month was significantly lower in Ob group (+93% vs +115%; P = 0.002), as well as RLVBWR increase (+0.59% vs +0.79%; P < 0.001). The RLV-1M represented 66.2% of initial TLV in Ob group compared with 73.8% (P = 0.005) in NonOb group. This delay in relative volumetric gain persisted at 6 months (+105.4% vs +137.6%; P = 0.009), the RLV-6M representing 71.2% vs 82.4% of initial TLV (P = 0.014).
  
  
  CONCLUSIONS
  In a methodologically robust trial in the first cohort reported up to date, the regenerative response in obese patients was comparatively slower based on their initial TLV or body weight.
authors: *Departments of Digestive Surgery and Transplantation †Pathology ‡Radiology §Oncology, CHU, Univ Nord de France, Lille, France.
authors: Stéphanie
authors: S
authors: Truant
authors: Ahmed Fouad
authors: AF
authors: Bouras
authors: Gheorghe
authors: G
authors: Petrovai
authors: David
authors: D
authors: Buob
authors: Olivier
authors: O
authors: Ernst
authors: Emmanuel
authors: E
authors: Boleslawski
authors: Mohamed
authors: M
authors: Hebbar
authors: François-René
authors: FR
authors: Pruvot
mesh_terms: D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008107:Liver Diseases / Q000601:surgery*; D008115:Liver Regeneration / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D009929:Organ Size; D011183:Postoperative Complications; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome