title: Systematic review of haemorrhage and rupture of hepatocellular adenomas.
abstract: BACKGROUND
  Although benign in itself, hepatocellular adenoma (HCA) can be complicated by hormone-induced growth, and subsequent haemorrhage and rupture. The exact risk of haemorrhage and rupture is not known. This systematic review of the literature was carried out with the aim of estimating the risk of haemorrhage and rupture in HCA.
  
  
  METHODS
  A systematic literature search of the PubMed and Embase databases was performed for all articles relevant to haemorrhage and/or rupture of HCA, published between 1969 and March 2011.
  
  
  RESULTS
  Twenty-eight articles met the selection criteria, containing a total of 1176 patients. Haemorrhage was reported with an overall frequency of 27·2 per cent among patients, and in 15·8 per cent of all HCA lesions. Rupture and intraperitoneal bleeding were reported in 17·5 per cent of patients. Bleeding was the first symptom in 68·5 per cent of patients with a bleeding HCA. Six of 13 articles reporting the size of HCA lesions in which bleeding occurred mentioned haemorrhage in HCAs smaller than 5 cm.
  
  
  CONCLUSIONS
  Haemorrhage and rupture are common in patients with HCA.
authors.affiliation: Department of Surgery, Erasmus Medical Centre, Rotterdam, The Netherlands. s.vanaalten@erasmusmc.nl
authors.forename: S M
authors.initials: SM
authors.lastname: van Aalten
authors.forename: R A
authors.initials: RA
authors.lastname: de Man
authors.forename: J N M
authors.initials: JN
authors.lastname: IJzermans
authors.forename: T
authors.initials: T
authors.lastname: Terkivatan
mesh_terms: D018248:Adenoma, Liver Cell / Q000150:complications* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D006470:Hemorrhage / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D008113:Liver Neoplasms / Q000150:complications* / Q000601:surgery; D008875:Middle Aged; D012307:Risk Factors; D012422:Rupture, Spontaneous / Q000209:etiology / Q000517:prevention & control; D055815:Young Adult