The aggressive nature of the odontogenic keratocyst: is it a benign cystic neoplasm? Part 1. Clinical and early experimental evidence of aggressive behaviour.

In this, the first of three articles on the aggressive nature of the odontogenic keratocyst (OKC), there is a review of clinical and histological observations which indicated that this was an aggressive lesion with a predilection for recurrence unlike the majority of other jaw cysts. This led to the tentative suggestion that the OKC might be a benign neoplasm. Subsequently there were early laboratory investigations that compared proliferation rates of the OKC epithelium with other jaw cysts, comparative enzyme histochemistry to assess aspects of its metabolism and markers that would enable accurate presurgical diagnosis of this cyst. Comparative studies were also pursued on the walls of the OKC and other jaw cysts to identify factors that might influence the capacity of the OKC to resorb the bone surrounding it. The clinical and laboratory studies reviewed in this section provided cogent presumptive evidence of the distinctively aggressive nature of the OKC that led numbers of investigators to pursue immunocytochemical and genetic studies on this cyst. Parts 2 and 3 of this series review this work.