Spectrum of histological features in non-alcoholic fatty liver disease.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) has become an Important entity globally, including in India and other Asian countries. Morphological evaluation of a liver biopsy is necessary for the diagnosis, staging and possibly management of this disease. However, the spectrum of changes in the liver, their evolution, Interrelationships and implications are incompletely understood. We aimed to study the spectrum of histological abnormalities in NAFLD. METHODS: The study material was drawn from a pool of 80 liver biopsies diagnosed in our laboratory as NAFLD, 67 retrieved retrospectively from our records and 13 obtained prospectively with complete clinical data. After comprehensive histological assessment, a detailed analysis was done of 32 of those categorized as definitive NAFLD on the basis of a dependable history of no alcohol Intake and seronegativity for hepatitis virus B and C Infections. RESULTS: Fatty change was preferentially seen in acinar zones 2 and 3, more so in the former. Steatotic cells varied in size; some large ones were non-spherical. Steatosis alone was present in more than a quarter of the cases and steatosis along with inflammation was present in half. The magnitude of steatosis correlated with inflammation, while both these seemed to correlate with hepatocyte Injury and fibrosis. CONCLUSION: A proportion of patients with NAFLD show only hepatic steatosis. An Increasing grade of steatosis is associated with greater Inflammation, hepatocyte injury and acinar fibrosis. Preferential involvement of acinar zone 2 by steatosis, the morphology of the steatotic cells, and nature and location of inflammation are important in the diagnosis of NAFLD and its differentiation from other causes of fatty liver.

CD99 expression in hepatocellular carcinoma: an immunohistochemical study in the fibrolamellar and common variant of the tumour.

Histological diagnosis of hepatocellular carcinoma (HCC) in biopsy and fine needle aspiration material can pose difficult problems. This is particularly so in the fibrolamellar variant of the tumour (FLHCC) which has biological features distinctly different from those of common HCC (CHCC). Expression of CD99, a membrane localised glycoprotein which is known to be a feature of diagnostic importance in several malignant neoplasms was looked for in immunohistochemical preparation of tissue material from 18 cases of HCC, 6 FLHCC and 12 CHCC accessioned in our department. Positive staining of variable degrees and intesity was observed in all 18 cases. Non-neoplastic hepatocytes, normal or others and all the 18 other cases of non-HCC cancers outside the liver or metastatic within the liver were negative. In some cases, mostly of FLHCC, a definitive diagnosis could be suggested on the basis of CD99 positivity. It is concluded that in cases of HCC, particularly in small specimens and in FLHCC, immunostaining for CD99 will be of significant help in diagnosis.