DNA-ploidy studies in a keratocyst undergoing subsequent malignant transformation

Using techniques that allow flow cytometry to be performed on tissue stored in paraffin wax, we have examined the DNA content of cells from an odontogenic keratocyst which underwent malignant transformation. On histological examination, the primary lesion was an odontogenic keratocyst showing dysplastic changes within the squamous epithelium. Flow cytometry revealed a prominent, abnormal DNA stemline, which was also present in the subsequent squamous cell carcinoma.