Prevention of Second Primary Tumors by an Acyclic Retinoid, Polyprenoic Acid, in Patients with Hepatocellular Carcinoma

Abstract

Retinoid is a collective term which indicates vitamin A (retinol) and its derivatives. Retinoid has a variety of functions such as growth promotion, maintenance of reproduction and dark adaptation. Retinoid also regulates cell differentiation and tissue morphogenesis. Sinceabnormality in the differentiation induces cellular atypia and that of the morphogenesis induces structural atypia, retinoid has important effects which inhibit carcinogenesis.