Granular cell ameloblastoma showing desmoplasia.

Our case of ameloblastoma had a surprisingly long 25 year history, with abnormally large dimensions, a multilocular diffuse-mixed radiographic picture, and was histopathologically diagnosed as granular cell ameloblastoma with desmoplasia. To the best of our knowledge, this is the first ameloblastoma ever reported, that has shown combined features of granular cells, desmoplasia, ameloblastic follicles, plexiform, and acanthomatous patterns. The nature of granular cells in this type of tumor and the significance of their presence have also been reviewed. From the studies on ameloblastomas to date, it seems that the old belief that granular cell ameloblastoma is the most aggressive variant of ameloblastoma is a myth, and in all probability, granular cells are just a transitional or matured phase in the life cycle of ameloblastomas, starting with normal stellate reticulum-like cells, leading to a production of granules and finally leading to degeneration and formation of cystic areas.