Tenascin is an extracellular matrix glycoprotein known to be an essential factor for the modulation of reciprocal interactions between the epithelium and mesenchyme during embryogenesis and tumourigenesis. The interactions between the expression of tenascin in the liver of Syrian golden hamster and the development of bile duct cancer in an Opisthorchis viverrini-associated cholangiocarcinoma model were investigated. The tenascin was expressed in connective tissues surrounding the dilated ducts, ductal rims and the stroma of cancers, and strongly in the stroma flame of necrotic cancer nodules. The mRNA signal for tenascin was also recognized in the stroma cells. The potential roles of tenascin as prognostic tumour markers are discussed.