title: Hibernoma: a clinical model for exploring the role of brown adipose tissue in the regulation of body weight?
abstract: BACKGROUND
  Hibernoma is a rare benign tumor histologically similar to brown adipose tissue. Some studies reported weight loss in patients with this tumor; however, the mechanisms have never been investigated.
  
  
  OBJECTIVE
  The purpose of this study is to explore the impact of hibernoma resection on the whole-body metabolism.
  
  
  METHODS
  A 68-year-old woman was examined after a weight loss of 10 kg in 6 months. Body composition, food intake, physical activity, blood levels of thyroid hormones, and lipid profile were assessed before surgery and during 1 year after surgery. The patient's resting energy expenditure (REE) over time was compared to a control group of 18 matched healthy volunteers.
  
  
  RESULTS
  Within 1 year after hibernoma resection, the patient gained 15 kg of body weight. This was associated with fat mass gain (+41%), mainly in the abdominal region (+48%). The patient also developed hepatic nonalcoholic steatosis, mild hypertriglyceridemia, and reduced levels of high-density lipoproteins. REE increased during the dynamic phase of weight gain, compared to the presurgery measurement, and returned to baseline after 1 year. Food intake was increased by 37.5% 6 weeks after resection of the hibernoma and returned to baseline values within 6 months.
  
  
  CONCLUSIONS
  In our study conditions, hibernoma did not alter REE, but weight gain did. Specific physical activities and dietetic follow-ups are suggested for those patients to prevent excess fat mass gain and metabolic disorders after hibernoma resection. More studies should focus on hibernoma mechanisms inducing weight loss.
authors.affiliation: Centre Jean Perrin (E.G., E.T., R.P., F.M., P.G., C.M., X.D.), Clermont-Ferrand F-63011, France; Institut National de la Recherche Agronomique (E.G., F.C., L.M., B.M.), Unité Mixte de Recherche (UMR) 1019, Unité de Nutrition Humaine (UNH), Centre de Recherche en Nutrition Humaine d'Auvergne, F-63000 Clermont-Ferrand, France; Clermont University (E.G., B.M.), University of Auvergne, UNH, BP 10448, F-63000 Clermont-Ferrand, France; Centre d'Investigation Clinique (E.G., E.T., X.D.), Inserm U501, Clermont-Ferrand, F-63000, France; EA 4677 Equipe de Recherche sur les Traitements Individualisés des Cancers (E.T.), F-63011 Clermont-Ferrand, France; Inserm (M.L.), Univ Paris-Sud 11, Faculté de Médecine Paris-Sud, UMR-S693, Le Kremlin Bicêtre, F-94276, France; and Translational Oncology EA3846 (X.D.), University of Auvergne, F-63000 Clermont-Ferrand, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Gadea
authors.forename: Emilie
authors.initials: E
authors.lastname: Thivat
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Paulon
authors.forename: Florence
authors.initials: F
authors.lastname: Mishellany
authors.forename: Pierre
authors.initials: P
authors.lastname: Gimbergues
authors.forename: Frédéric
authors.initials: F
authors.lastname: Capel
authors.forename: Laurent
authors.initials: L
authors.lastname: Mosoni
authors.forename: Charles
authors.initials: C
authors.lastname: Merlin
authors.forename: Marc
authors.initials: M
authors.lastname: Lombès
authors.forename: Béatrice
authors.initials: B
authors.lastname: Morio
authors.forename: Xavier
authors.initials: X
authors.lastname: Durando
mesh_terms: D002001:Adipose Tissue, Brown / Q000473:pathology / Q000502:physiology*; D000368:Aged; D001835:Body Weight / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D006801:Humans; D008067:Lipoma / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D008954:Models, Biological; D015431:Weight Loss / Q000502:physiology*