Intralocular Papillary Change in Cystic Ameloblastomas

The locules in cystic ameloblastomas are generally lined by a smooth flat layer of epithelium. Although variations in the classical microsopic manifestation of ameloblastomas has been reported, only one case in a series of 108 ameloblastomas presented with a randomly detected papilloma virus induced verucca in the lining of one of the locules (Raubenheimer, van Heerden and Noffke, 1995). Objective: This study was aimed at determining the microscopic changes associated with intralocular papillary proliferations in a series of resected specimen of cystic ameloblastomas. Methods: Fifteen jaw resections for ameloblastomas were hemisected and the linings of the locules and cysts examined for papillary change. Results: Three cases with papillary growths were identified. The tumors of all three cases measured more than 12cm in greatest diameter. Microscopic examination showed odontogenic carcinoma as cause for the papillarity in two cases and adenomatoid odontogenic tumorous change in one. Effacement of the locular architecture radiologically in the former two cases corresponded with the papillary change. Conclusion: This study indicates that the locules of large ameloblastomas should be examined carefully for papillarity which could be indicative of important secondary change.