32. Histological differences between non-cirrhotic portal fibrosis and extra-hepatic portal vein obstruction

Abstract

Background and Aims: Both non-cirrhotic portal fibrosis (NCPF) and extrahepatic portal venous obstruction (EHPVO) are important non-cirrhotic causes of portal hypertension (PH) in India. In this study we analyzed and documented the histopathological differences in liver biopsies from patients diagnosed with NCPF and EHPVO. Methods: Patients presented with PH were categorized as NCPF and EHPVO based on the Asia Pacific association for the study of liver (APASL) criteria. Minimum adequacy criteria were defined and 69 liver biopsies from patients with NCPF and 100 liver biopsies from EHPVO patients were included, over a period of twelve years (2004–2016). All histological parameters were pre- defined and three experienced pathologists analyzed the biopsies after reaching consensus on each finding. Institute ethics committee clearance was taken. Results: Though histological features were overlapping, phlebosclerosis of intra-hepatic branches of portal vein (PV), peri-portal aberrant vascular channels, remnant portal tracts and hepatic fibrosis beyond the portal tracts without formation of complete hepatic nodules were common findings in biopsies from patients with NCPF; while, in EHPVO lobular architecture of liver was mostly maintained and intra-hepatic phlebosclerosis, aberrant vascular channels and fibrosis beyond portal tracts were significantly less. Conclusions: Though most histological features between NCPF and EHPVO were overlapping, phlebosclerosis of the intrahepatic branches of PV with formation of peri-portal aberrant collateral channels, remnant portal tracts and fibrosis beyond portal tracts characterized NCPF over EHPVO. Correlation of suggestive histological features with clinico-radiological findings, hepatic venous pressure gradient, PV pressure or intra-splenic pressure would help to reach a conclusive diagnosis. The authors have none to declare.