%0 Journal Article %T Giant Hepatic Cyst with Septal Structure: Diagnosis and Management %A Toshihiro Sato %A Michitaka Imai %A Kazunao Hayashi %A Osamu Isokawa %A Tatsuya Nomura %A Yoshiaki Tsuchiya %A Takashi Kawasaki %J International Journal of Hepatology %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/981975 %X The hepatic cyst is a common benign liver tumor, and no surgical treatment is necessary. However, it is difficult to correctly diagnose the giant hepatic cyst containing the solid septal structures inside, from the malignant cystadenocarcinomas. The various imaging modalities such as computed tomography, magnetic resonance imaging, and ultrasonography, have been developed and are useful for the diagnosis of these liver tumors. Reviewing the other reports in this paper, the combination of more than 2 modalities will help to diagnose these tumors; however, the malignant potential is unable to be excluded if the tumor is huge. Therefore, the surgical resection should be considered for the huge hepatic cysts with septal structures if the correct diagnosis is unable to be made. For example, when the hemorrhages cause the granulation in the septa which often shows neovascularization, the imaging modalities are unable to define this situation from the malignant tissue with hypervascularity. Therefore, with the careful review of other reports, we conclude that if the imaging studies show the possible malignant potential or the sizing-up is marked, the surgical treatment should be considered with the consent from the patients. 1. Introduction To date, cystic diseases of the liver are being encountered more frequently in the clinical setting because of advancements in various diagnostic imaging modalities. While some cases are easy to diagnose on the basis of medical history and clinical symptoms, such as metastatic hepatic tumors and hepatic abscesses, it becomes difficult to distinguish simple hepatic cysts from malignant diseases in some cases with diverse findings or intracystic hemorrhage and infection [1]. To update the information for the diagnosis of the hepatic cyst and help the therapeutic decision, we reviewed reports showing our representative hepatic cyst case mimicking the biliary cystadenocarcinoma in this paper. 2. Clinical Features of Primary Cystic Liver Tumors 2.1. Simple Cyst Hepatic cysts are the most frequently occurring, benign, space-occupying lesions of the liver. These cysts contain fluid, and their inner walls are covered with a layer of epithelial cells [2]. It can be classified by etiology into congenital and acquired cysts. The former is divided into parenchymal and biliary cysts, and parenchymal cysts can be isolated or polycystic. Acquired cysts are broadly classified as traumatic, inflammatory (including parasitosis), and neoplastic cysts. The ultrasonography (US) shows a well-circumscribed anechoic lesion with increased %U http://www.hindawi.com/journals/ijh/2013/981975/