Comparative Aspects of Rat and Human Hepatocellular Preneoplasia and Neoplasia

In a “comparative histomorphological review of rat and human hepatocellular proliferative lesions”, Thoolen and colleagues1 stated that “there are major similarities in the diagnostic features, growth patterns and behavior of both rat and human proliferative hepatocellular lesions and in the process of hepatocarcinogenesis”. I fully agree with this statement, but in view of its far-reaching consequences for the evaluation of rodent carcinogenesis bioassays and the early detection of precursors of human hepatocellular adenomas (HCA) and carcinomas (HCC) I draw your attention to several critical comparisons and conclusions concerning the significance of preneoplastic foci of altered hepatocytes (FAH), called “foci of cellular alteration” in the review.