The histologic similarity between craniopharyngioma and odontogenic lesions: a reappraisal.

The histologic similarities between the craniopharyngioma and the ameloblastoma are well recognized and supported by their common embryologic origin from oral ectoderm. Differences in these lesions include a greater tendency for craniopharyngiomas to be cystic and form ghost cells and calcifications. The keratinizing and calcifying odontogenic cyst (KCOC), a lesion that features proliferating ameloblastic epithelium, ghost keratin, calcification, and cyst formation, may more precisely mimic the craniopharyngioma. The histologic features of twenty-seven craniopharyngiomas were studied. Twenty cases resembled KCOC microscopically. Two examples duplicated the histologic features of infiltrative ameloblastoma, while five showed characteristics of both lesions. This study shows that the range of histologic features in craniopharyngioma includes and spans both odontogenic lesions but more often simulates KCOC. The results suggest that the KCOC and the ameloblastoma may be closely related developmentally.