title: Intracystic hemorrhage of a simple liver cyst mimicking a biliary cystadenocarcinoma.
abstract: Simple liver cysts are rarely complicated by intracystic hemorrhage. We encountered a case of simple liver cyst that was morphologically similar to biliary cystadenocarcinoma, which was complicated by asymptomatic intracystic hemorrhage and successfully treated by right lobectomy. A large cystic lesion of the liver was detected in a 57-year-old woman during a mass screening health check. Abdominal ultrasonography (US) revealed that the cystic lesion, containing many hyperechoic papillary structures, occupied almost the entire region of the right hepatic lobe. In addition, a round mural nodule, measuring approximately 5 cm in diameter, was detected in the cystic wall. Abdominal computed tomography (CT) revealed that the inner part of the cystic lesion showed homogeneous low density, but CT did not show the round nodule detected by US. On T1-weighted sequence of magnetic resonance imaging (MRI), the lesion showed homogeneous high signals, together with a low-signal tumorous lesion in the cystic wall. T2-weighted sequence of MRI showed unhomogeneous high signals, together with high signals in the tumorous part. These findings did not exclude the possibility of a malignant cystic tumor, such as biliary cystadenocarcinoma. Therefore, right lobectomy was performed. Histological examinations of resected tissue specimens revealed that the lesion was a liver cyst containing a large amount of blood clot, and that the tumorous lesion detected by US and MRI was a large mass of blood clot which was partly liquefied. This case indicates the diagnostic importance of the morphological discordance between CT and US or MRI findings for liver cyst containing a large amount of blood clot.
authors.affiliation: Department of Gastroenterology, Gifu Prefectural Tajimi Hospital, 5-161 Maehatacho, Tajimi 507-8522, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kitajima
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Okayama
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hirai
authors.forename: Kazuki
authors.initials: K
authors.lastname: Hayashi
authors.forename: Hideto
authors.initials: H
authors.lastname: Imai
authors.forename: Tetsu
authors.initials: T
authors.lastname: Okamoto
authors.forename: Shigeru
authors.initials: S
authors.lastname: Aoki
authors.forename: Shinji
authors.initials: S
authors.lastname: Akita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Gotoh
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Ohara
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Nomura
authors.forename: Takashi
authors.initials: T
authors.lastname: Joh
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Makoto
authors.initials: M
authors.lastname: Itoh
mesh_terms: D001661:Biliary Tract Neoplasms / Q000175:diagnosis*; D003536:Cystadenocarcinoma / Q000175:diagnosis*; D003560:Cysts / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D006470:Hemorrhage / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006498:Hepatectomy; D006801:Humans; D008107:Liver Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D014463:Ultrasonography