138 Extrahepatic Biliary Mucinous Cystic Neoplasm: A Case Report. (11th January 2018)

• Record Type: Journal Article
• Authors: AlZubaidi, Yasir; Abdulsattar, Jehan; Cruz, Nestor Dela
• Is Part Of: American journal of clinical pathology. Volume 149(2018)Supplement 1
• Page Start: S59
• Page End: S60
• Publication Date: 2018-01-11
• Subjects: Diagnosis, Laboratory -- Periodicals; Pathology -- Periodicals; 616.07
• DOI: 10.1093/ajcp/aqx119.137
• Languages: English
• ISSNs: 0002-9173

Abstract

Abstract: Biliary mucinous cystadenomas (BMCs) are relatively rare cystic neoplasms of the liver, and extrahepatic BMCs are even rarer. These tumors may be misdiagnosed as simple cysts, but it is important to make the correct diagnosis, given that the treatment of choice for BMC is complete excision to prevent recurrence. Up to 85% of BMCs occur in women, and the distinctive mesenchymal ovarian-type stroma is found only in women. The mean age at diagnosis is roughly 45 years. Whether the stroma represents an ovarian remnant, a recapitulation of periductal fetal mesenchyme seen in these organs, or some other phenomenon is not known. BMCs without ovarian stroma are either other types of cysts or intraductal papillary neoplasms. Most mucinous cystadenomas are intrahepatic (84%). Carcinomatous transformation is fairly uncommon in these tumors. Nevertheless, a cystic lesion ought to be thoroughly examined to exclude the presence of carcinoma or dysplasia. Here we report a case of 45-year-old woman who presented with a 1.5 cm solitary multilocular sharply circumscribed cystic mass in her left extrahepatic bile duct. Microscopic examination revealed a multiloculated cyst that is lined by a single layer of tall columnar cells with abundant apical mucin in background of ovarian like stroma. No necrosis or atypical mitosis was noted. Immunohistochemical stains showed positive ER, PR, and inhibin of stromal cells. Based on the morphology and immunohistochemistry, a diagnosis of extrahepatic biliary mucinous cystic neoplasm was rendered.