Discrimination of parakeratinised odontogenic keratocysts from other odontogenic and non‐odontogenic cyst types by expression of a 38kd cell‐surface glycoprotein

We have identified strong expression of a 38-kD cell surface glycoprotein (gp38), a marker of basal cell carcinomas (BCCs), in basal and suprabasal epithelial cell membranes of parakeratinised odontogenic keratocysts. In contrast, orthokeratinised cysts and most other odontogenic cyst types, ameloblastomas, normal stratified oral epithelium, cell rests of Malassez and glands of Serres, all proved negative. To our knowledge this is the first histochemical marker to distinguish between these major cyst types. It has obvious uses in the diagnosis of inflamed keratocysts and the separation of ameloblastomas from BCCs and may find a role in studies of the developmental biology of other odontogenic structures.