# A Rare Case: Adenomatoid Odontogenic Tumor Mimicking Follicular Cyst in a Young Patient
## 3 Discussion  
AOT is a rare benign epithelial odontogenic tumor and can mimic a follicular or odontogenic cyst. This type of tumor affects women more frequently (1.9:1) in their second decade of life [18]. It usually occurs in the anterior portion of the upper jaw and the most common site is the canine region. An impacted canine is associated with follicular AOTs in almost 70% of cases [19]. There are three clinicopathologic variants of AOT, and despite their different locations, the histological appearance of these three lesions remains the same.  
The follicular type of AOT typically presents as a round or ovoid unilocular radiolucency with well-defined contours associated with the crown of an unerupted tooth, resembling a dentigerous or follicular cyst.  
In contrast, the extradilicular intraosseous AOT lacks any association with an unerupted tooth. However, it is often found situated between, above, or adjacent to the roots of erupted teeth.  
The peripheral variant of AOT manifests as a gingival fibroma or e  
Figure 8: (H&E stain): (**A**) tubular structure lined by single-layered tubular epithelium (20\(\times\)); (**B**) small intralesional foci of calcification and hemorrhage (40\(\times\)); duct-like structure lined by cuboidal cells and pseudo-rosettes pattern (40\(\times\)).  
Figure 7: (H&E stain): (**A**) cystic fiboconnectival wall lined by odontogenic epithelium with intraluminal solid epithelial proliferation (2\(\times\)); (**B**) cribribriform peripheral areas alternating with solid pale nests (10\(\times\)); (**C**) multinodular epithelial proliferation admixed with hemorrhagic areas.  
Histologically, it is characterized by sheets of polygonal cells within a fibrous connective tissue matrix. This matrix contains mesenchymal cell populations that produce type I and III collagen, hence classifying AOT as a mixed odontogenic tumor [20; 21; 22].  
Common features of this tumor include KRAS mutations and activation of the mitogen-activated protein kinases pathway, which are also found in certain cancer types [8]. The diagnosis of AOT is essentially morphology-based, considering its typical histologic features, which aids mostly differential diagnosis with other benign epithelial odontogenic tumors. Immunohistochemistry doctors not represent a valid diagnostic tool. In cases of morphology overlapping with other entities of this category, the correlation with clinical and radiologic appearance plays a pivotal role.  
Treatment for most lesions typically involves enucleation. While some cases of recurrence have been reported in the literature, only one has been well documented [23].  
The follicular cyst and the odontogenic adenomatoid tumor can both appear clinically and radiographically in a similar manner.  
This case was particularly challenging due to the difficulty in establishing a diagnosis based on the radiographic and clinical findings. Both dentigerous cysts and AOT are benign, encapsulated lesions, making enucleation relatively straightforward.  
Despite the lesion's considerable size, the outcome was favorable, with excellent healing and no recurrence observed.