Genetic Profile of Adenomatoid Odontogenic Tumor and Ameloblastoma. A Systematic Review

Purpose: To perform a comprehensive and systematic critical appraisal of the genetic alterations reported to be present in adenomatoid odontogenic tumor (AOT) compared to ameloblastoma (AM), to aid in the understanding in their development and different behavior.Methods: An electronic search was conducted in PubMed, Scopus, and Web of Science during March 2021. Eligibility criteria included publications on humans which included genetic analysis of AOT or AM.Results: A total of 43 articles reporting 59 AOTs and 680 AMs were included. Different genomic techniques were used, including whole-exome sequencing, direct sequencing, targeted next-generation sequencing panels and TaqMan allele-specific qPCR. Somatic mutations affecting KRAS were identified in 75.9% of all AOTs, mainly G12V; whereas a 71% of the AMs harbored BRAF mutations, mainly V600E.Conclusions: The available genetic data reports that AOTs and AM harbor somatic mutations in well-known oncogenes, being KRAS G12V/R and BRAFV600E mutations the most common, respectively. The relatively high frequency of ameloblastoma compared to other odontogenic tumors, such as AOT, has facilitated the performance of different sequencing techniques, allowing the discovery of different mutational signatures. On the contrary, the low frequency of AOTs is an important limitation for this. The number of studies that have a assessed the genetic landscape of AOT is still very limited, not providing enough evidence to draw a conclusion regarding the relationship between the genomic alterations and its clinical behavior. Thus, the presence of other mutational signatures with clinical impact, co-occurring with background KRAS mutations or in wild-type KRAS cases, cannot be ruled out. Since BRAF and RAS are in the same MAPK pathway, it is interesting that ameloblastomas, frequently associated with BRAFV600E mutation have aggressive clinical behavior, but in contrast, AOTs, frequently associated with RAS mutations have indolent behavior. Functional studies might be required to solve this question.

Adenomatoid odontogenic tumor: a report of two unusually large lesions in the mandible

Introduction/Objective Adenomatoid odontogenic tumor (AOT) is an uncommon benign odontogenic tumor representing 3 to 7% of all odontogenic tumors. This tumor was first reported as adeno-ameloblastoma by Bernier and Tiecke in 1950 as it was initially assumed to be a type of ameloblastoma. In 1969, Philipsen and Bern proposed the term adenomatoid odontogenic tumor which was subsequently adopted by WHO and became the accepted terminology for this tumor. AOT is classified as a tumor of odontogenic epithelium but occasionally abnormal hard tissues consistent with dentinoid material may also be present as part of the tumor. AOT tends to occur in younger patients and 50% of the cases are diagnosed in teenagers. It occurs twice as commonly in females and frequently involves the anterior maxilla. Radiographically, AOT can appear as a radiolucent or mixed lucent-opaque lesion and may be associated with an impacted tooth. Methods/Case Report We report two unusually large expansile lesions of AOT that presented in the mandible. In the first case, the tumor presented as an expansile radiolucent lesion involving the right posterior mandible in a 32 year old female. In the second case, the tumor presented as an expansile mixed lucent-opaque lesion involving the left anterior mandible in a 21 year old female. The clinical presentation, radiographic and imaging findings, histopathologic features and treatment of these two cases will be discussed. The recommended treatment for AOT is surgical excision. The prognosis is good as this tumor seldom recurs after excision. Results (if a Case Study enter NA) NA Conclusion AOT is considered to be a non-aggressive, non-invasive and slow growing benign neoplasm. It is usually discovered on routine radiographic examination as the lesion is usually small and asymptomatic at the time of diagnosis but occasional cases that are larger in size have been reported in the literature.

Adenoid Ameloblastoma with Dentinoid

Ameloblastoma and adenomatoid odontogenic tumors are the most common odontogenic neoplasms. However, hybrid variant of the two lesions, Adenoid Ameloblastoma with dentinoid is extremely rare. The lesion comprises of characteristic histopathological features of Ameloblastoma and Adenomatoid odontogenic tumor and also shares certain clinical characteristics with either of the entities. Adenoid Ameloblastoma with dentinoid may be considered at the more aggressive end of spectrum of benign odontogenic neoplasms. Owing to the frequent tendency of lesion to be underdiagnosed, careful histopathological screening of submitted biopsies is warranted. With the increase in number of reported cases in the recent years, it is likely to be included as a separate entity in the upcoming WHO classification. The present systematic review aims at collectively presenting the demographic, clinical, radiographic and histopathological features, treatment performed along with its outcome for all the cases of Adenoid Ameloblastoma with dentinoid reported in scientific literature till date. Keywords: Hybrid Odontogenic Tumor; Adenomatoid Odontogenic Tumor; Adenoameloblastoma; dentinoameloblastoma; Immunohistochemistry

Adenomatoid Odontogenic Tumor- A Rare Case Report of “Two Third Tumor”

Adenomatoid odontogenic tumor (AOT) is a rare odontogenic origin tumor that manifests as a slow-growing cystic neoplasm in the anterior maxilla, often in conjunction with an impacted tooth. AOTs are divided into three kinds based on their histology: follicular, extrafollicular, and peripheral. Because the source of the AOT is unknown, it's impossible to say whether the lining of an associated cyst reflects the cause i.e. a real dentigerous cyst, a cystic alteration within an AOT, or a separate entity. The diagnosis and treatment should be determined following a thorough clinical, radiographic, and histological investigation. The presented case is a rare occurrence of its sort due to the favorable patient's age and the AOT's site in the lower jaw. The current study reports on a case with follicular AOT in the anterior mandibular region (a rare location), with unusual histomorphology (snow flake and calcified areas) associated with impacted 43 and retained 83.