Ameloblastoma with adenoid features: A series of eight cases

Adenoid Ameloblastoma with Dentinoid

“…CK14 has been identified as the primary, intermediate filament of odontogenic epithelium, present in the dental lamina, reduced enamel epithelium, duct-like structures of AOT, and in almost all the cells of the enamel organ associated with the secretory activity of the odontogenic epithelial cells [52]. Strong immunopositive staining for CK14 was observed in many central and peripheral cells of tumor islands and the adenoid structures and surrounding cells in 6/8 cases reported by Adorno-Farias et al [24]. The negative expression of CK14 suggests the regions of advanced amelogenesis with the loss of cellular secretory activity, indicating the protective stage of amelogenesis [52].…”

“…Multilocularity was observed in only 2/8 cases reported by Adorno-Farias et al (2018) [24]. It is observed in the radiographic images of AM, wherein the tumor exhibits the septae of bone extending into the radiolucent tumor mass [30].…”

“…Yamazaki et al found certain areas of amyloidbased extracellular material indicated by positive Congo Red staining [11]. Adorno-Farias et al demonstrated pseudoducts with PAS-positive material [24]. Loyola et al [13] stated that although basophilic mucoid material may be observed within the duct-like spaces, secretory component was not detected.…”

Update on Odontogenic Tumors: Proceedings of the North American Head and Neck Pathology Society

“…Adenoid ameloblastoma was initially described by Charles Waldron in 1959, as "an essentially adenoid type growth which is not typical of either salivary gland tumors or as ameloblastomas as they are usually recognized" [28]. In 2015, a more recent article by Loyola et al brought adenoid ameloblastoma to the forefront presenting 5 additional cases and, to date, less than 40 cases have been reported with numerous reports occurring in the last five years [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42]. Given the small number of cases, it is difficult to draw conclusions, but these tumors appear to present in a wide age range (19-79, mean 43 years), as large tumors with a mean size of 4.4 cm, with a maxillary predilection (67%), and have a relatively high recurrence rate (10/13, 77%) [28,[32][33][34][35][36][37][38][39][40][41][42].…”

“…Adenoid ameloblastoma is challenging diagnosis as it exhibits features of a dizzying array of odontogenic tumors as well as salivary tumors including: adenomatoid odontogenic tumor, adenoid cystic carcinoma, basal cell adenocarcinoma, adenomatoid odontogenic tumor, ameloblastoma, ameloblastic carcinoma, the ghost cell family of tumors, clear cell odontogenic carcinoma, and odontogenic carcinoma with dentinoid [43]. Adenoid ameloblastoma is positive for CK14, P63 and AE1/3, but negative for S-100, CK7, and P53 [29,42]. Immunohistochemical studies eliminate biphasic salivary entities from the differential diagnosis (including adenoid cystic carcinoma and basal cell adenocarcinoma) as adenoid ameloblastoma is monophasic.…”