Enhanced Survival and Absence of Progressive Growth of Transplanted Rat Liver Altered Eosinophilic Foci and Neoplastic Nodules in Phenobarbital-Treated Rats<xref ref-type="fn" rid="FN2">2</xref>

Abstract

Hepatocellular altered eosinophilic cell foci and neoplastic nodules induced in inbred F344 male albino rats by the feeding of N-2-fluorenylacetamide were transplanted into the inguinal mammary fat pads of syngeneic animals to assess their ability to produce neoplasms. Treatment of one-half of the recipients with the neoplasm promoter phenobarbital sodium enhanced survival of both types of transplants. However, at the end of 6 or 12 months of maintenance of recipients of altered foci and 6 months of maintenance of recipients of early and late nodules, no neoplasms occurred, in spite of persistence of abnormal cells at the transplant sites. Therefore, the conclusion was that these carcinogen-induced liver lesions possess limited growth capacity in this ectopic site and that transition to carcinoma under these conditions did not occur in high frequency.