# A Rare Case: Adenomatoid Odontogenic Tumor Mimicking Follicular Cyst in a Young Patient
## 1 Introduction  
Lesions of the jawbones encompass a wide spectrum of pathologies leading to challenges in differential diagnosis. These lesions can originate from tumors or cysts, and while most are benign, accurate differentiation is crucial. From a histological perspective, odontogenic tumors are classified based on their tissue of origin into three categories: epithelial, mesenchymal, and mixed epithelial and mesenchymal [1]. The symptoms of these lesions are variable; they can exhibit different growth patterns, sizes, and levels of aggressiveness. Many odontogenic tumors are asymptomatic or have minimal symptoms and are therefore often diagnosed during routine radiographic examinations [2]. Odontogenic cysts are pathological cavities originating from odontogenic tissues that occur in the tooth-bearing regions of the maxilla and mandible. These cysts have developmental or inflammatory origins. The four most common odontogenic cysts are periapical cysts, dentigerous cysts, residual cysts, and odontogenic keratocysts. These lesions are more frequently observed in males, typically between the fourth and sixth decades of life. The most affected area is the maxillary anterior region, followed by the mandibular molar region [3]. From a histological perspective, odontogenic tumors and cysts derive from the rests of Serres and Malassez. These remnants can remain quiescent or become activated by inflammatory or genetic factors. Their activation can lead to the formation of odontogenic cysts and tumors. The only tool we have for an accurate and definitive diagnosis is histological examination [4]. Clinical misdiagnoses between tumors and cysts are possible due to the similar clinical and radiological presentations of these lesions. The adenomatoid odontogenic tumor (AOT) is a rare, benign epithelial tumor characterized by its asymptomatic nature, noninvasive behavior, and slow growth. It was initially identified by [PERSON] in 1905 [5]. This tumor is more frequently observed in females,primarily during the second decade of life, and often associated with a permanent tooth that has not erupted. Typically, it manifests as a well-defined radiolucent lesion with expansile properties, predominantly located in the maxilla (70%). Additionally, these lesions may exhibit variable amounts of punctate calcifications. There are three recognized clinical and radiographic variants of AOT: (a) follicular, (b) extrafollicular, and (c) peripheral (or extraoseous) [6]. The 5 th edition of the World Health Organization (WHO) Classification of Head and Neck Tumors (2022) introduces significant updates that align with rapid advancements in sophisticated molecular investigations. These updates include interpretations that already impact therapy strategies [7]. Recent studies suggest that approximately 70% of sporadic adenomatoid tumors have a KRAS gene mutation. However, these mutations have not yet been precisely correlated with the clinical and pathological characteristics of the tumor [8]. Alongside AOTs, other oral manifestations include dental abnormalities, giant cell lesions of the jaws, and papillary lesions in the oral mucosa [9]. This interesting tumor often mimics other odontogenic lesions, earning it the name, \"master of disguise\", as exemplified in our case [5]. The radiographic features of AOT often resemble those of other odontogenic lesions, including follicular cysts, calcifying odontogenic cysts, calcifying odontogenic tumors, globule-maximally cysts, amelblastoma, odontogenic keratocysts, and periapical disease [10]. AOT commonly presents in association with unerupted permanent teeth, particularly canines, in about two-thirds of cases [11]. Unerupted permanent canines are frequently linked to another form of lesion known as the follicular cyst. Clinical misdiagnosis can occur due to similarities in both clinical presentation and radiological signs among many of these cysts. A follicular cyst, also known as a deniferous cyst, was initially described by [PERSON] in 1863 [12].