Fibrosis Regression of Advanced Chronic Liver Disease Outlined by a Novel Histological Classification

In the past, advanced chronic liver disease was considered irreversible, but with better understanding and improved treatments, it is now recognized that fibrosis is a dynamic process that can regress even when it has reached the stage of cirrhosis. We present the case of a 60-year-old male patient with advanced chronic liver disease due to chronic hepatitis B, whose follow-up liver biopsy revealed significant fibrosis regression after successful antiviral therapy. We confirmed the predominantly regressive pattern using the P-I-R classification, a new histological classification that defines the tissue features as predominantly "Progressive, Intermediate or Regressive" by comparing stroma to parenchymal ratios. Furthermore, we also point out the prognostic value of P-I-R classification, as the patient has remained free of decompensation over time. In this clinical case, we highlight important aspects of the pathophysiology and histopathology of cirrhosis regression, emphasizing its critical prognostic significance. Finally, familiarizing clinicians and pathologists with the application of the P-I-R classification may improve prognostication based on histology in patients with advanced liver disease.