Comparison between Prenatally Diagnosed Choledochal Cyst and Type-1 Cystic Biliary Atresia by CD56-Immunostaining Using Liver Biopsy Specimens

Abstract

Because it is difficult to distinguish preoperatively between a prenatally diagnosed choledochal cyst (CC) and type-1 cystic biliary atresia (BA) by ultrasound scanning or magnetic resonance imaging, some mode of discriminating between the 2 entities is required. The aim of this study was to investigate the immunohistological differences between prenatally diagnosed CC and type-1 cystic BA, using liver biopsy specimens immunostained for CD56. Five children with prenatally diagnosed CC and two children with prenatally diagnosed type-1 cystic BA were identified by fetal ultrasonography between 1985 and 2004. The control group included two children who were operated on at an earlier period due to postnatally diagnosed BA. Liver wedge biopsy in the right lobe was performed at the time of the radical operation. Histological findings of the CD56-stained liver biopsy specimens were classified into 4 categories each, with particular focus on staining distribution and intensity. The staining distribution was classified according to the scale 0 = no staining; 1 = some staining of bile ducts/ductules but staining in less than one-third of portal tracts; 2 = staining in one-third to less than two-thirds of portal tracts; and 3 = staining in more than two-thirds of portal tracts. Staining intensity was scored as follows: 0 = no staining, 1 = weak staining, 2 = moderate staining, and 3 = strong staining. The staining intensity and distribution in the CC group was zero in all 5 cases. The type-1 cystic BA group consisted of patients with scale 1 or 3 staining distribution and score 1 or 2 staining intensity. In the control group, staining distribution was 1 or 3, and staining intensity was 1 or 3. These results indicate that CD56-positive biliary duct cells are present in prenatally diagnosed type-1 cystic BA. The authors suggest that exploratory laparotomy might be avoided and, instead, immunohistological examination using liver biopsy specimens may be a reliable test for the differential diagnosis of CC and type-1 cystic BA in prenatally diagnosed neonates.

Cystic biliary atresia: an etiologic and prognostic subgroup

“…Other authors have suggested that to assess fibrosis [26] or biliary tract expression of neural cell adhesion molecule 1 (CD56) [27] may permit discrimination, although reported numbers are too small to be conclusive. Radioisotope scans have also been proposed [3,19,24].…”

Choledochal Cysts: Presentation, Clinical Differentiation, and Management

“…68 Moreover, immunohistochemical analysis of CD56-stained liver biopsy specimens from CC and CBA patients showed no CD56 positivity and less hepatic fibrosis in CC group compared with varying levels of CD56 positive hepatocytes and increased hepatic fibrosis in all prenatally diagnosed CBA. 70,71 …”

Key imaging features for differentiating cystic biliary atresia from choledochal cyst: prenatal ultrasonography and postnatal ultrasonography and MRI

“…than the normal development of the bile ducts, could contribute to the stable cyst size in utero [29]. Another theory suggested that overexpression of CD56 at the portal area represented dysregulation of the cell or intercellular matrix interactions in ductal plate remodeling in prenatal cBA patients [30]. These immune and inflammatory responses could affect various features of the size and growth patterns of cysts in cBA and CC prenatally.…”