title: Multicystic biliary hamartoma: A report of a rare entity and a review of the literature.
abstract: BACKGROUND
  Multicystic biliary hamartoma is a rare liver tumor that was first described in 2005. Only nine cases are reported in the literature and all of them originate from Eastern patient populations, specifically Japan and Korea.
  
  
  METHODS
  Herein we report the occurrence of the tenth multicystic biliary hamartoma reported to date, arising in a Caucasian American woman initially presenting with abdominal pain. At 4.7cm this is the second largest tumor reported to date and the only one arising in a Western patient population.
  
  
  CONCLUSIONS
  The patient underwent multimodality imaging and the tumor was biopsied preoperatively, but the diagnosis remained unclear. An extended right hepatectomy was performed for resection of her tumor, and the tumor was definitively diagnosed based on the surgically resected specimen. As all nine of the previously reported cases also underwent resection, the natural history of this lesion remains unknown. The lack of both recurrence and tumor spread in the previously reported cases indicates that this may be a benign lesion not requiring surgical resection unless symptomatic.
  
  
  CONCLUSIONS
  Multicystic biliary hamartoma is an extremely rare tumor. Increased awareness of the radiologic and pathologic features will likely lead to the diagnoses of further cases in both Western and Eastern populations and could potentially assist with preoperative diagnosis. The natural history and optimal management of this tumor remain uncertain.
authors.affiliation: Department of Surgery, Beth Israel Deaconess Medical Center, 110 Francis Street, Boston, MA 02215, United States. Electronic address: rbeard@bidmc.harvard.edu.
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Beard
authors.affiliation: Department of Pathology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, United States.
authors.forename: Eric U
authors.initials: EU
authors.lastname: Yee
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, United States.
authors.forename: Koenraad J
authors.initials: KJ
authors.lastname: Mortele
authors.affiliation: Department of Surgery, Beth Israel Deaconess Medical Center, 110 Francis Street, Boston, MA 02215, United States.
authors.forename: Khalid
authors.initials: K
authors.lastname: Khwaja
keywords: Biliary neoplasm; Cystic; Hamartoma; Honeycomb; Periductal