Adenoid ameloblastoma revisited: A discursive exploration of its histological dualism, molecular aberrations, and clinical recurrence.

Adenoid ameloblastoma (AA) is a rare benign but locally aggressive odontogenic tumor originating from the remnants of the dental lamina or enamel organ. It was newly incorporated into the 2022 WHO classification of odontogenic lesions, standing as the sole novel entity in this update. AA is also regarded as a hybrid tumor because of the combination of histological characteristics observed in both adenomatoid odontogenic tumors and ameloblastoma. Clinically, it presents similarly to other ameloblastoma variants, with patients typically exhibiting a painless, slow-growing jaw swelling. However, this subtype is noted for its more aggressive behavior, including a higher recurrence rate and greater local invasiveness. Histopathologically, AA is distinguished by an intricate arrangement of epithelial islands, cords, and strands, generating a cribriform architectural pattern, with peripheral palisading and central stellate reticulum-like formations. Immunohistochemical profiling reveals the expression of epithelial differentiation markers, including cytokeratins, and proliferative markers such as Ki-67, further corroborating its aggressive phenotype. While its precise etiopathogenesis remains obscure, the unique histological characteristics imply a potentially distinct underlying molecular pathway. Due to its aggressive nature, AA necessitates meticulous clinical and histopathological evaluation and tailored therapeutic strategies to mitigate recurrence risks and optimize patient prognoses. Furthermore, this review integrates histological and molecular insights from recent studies conducted after its inclusion in the updated WHO classification.

Changing Trends of Odontogenic Cysts and Tumors in Kenya: A 20-Year Retrospective Analysis.

OBJECTIVES: This study endeavors to bridge the long-term diagnostic and management gap through a comprehensive audit of odontogenic cysts and tumors in Kenya, offering crucial insights for both clinicians and policymakers. METHODS: Patient records (2001-2020) with odontogenic cysts and tumors were retrospectively abstracted from two major referral hospitals in Nairobi, Kenya, covering demographics, lesion location, and histological diagnosis. IBM SPSS Statistics for Windows, Version 29.0 (Released 2023; IBM Corp., Armonk, New York, United States) was used for data analysis which included all descriptive statistics, student t-tests, chi-square tests, and one-way ANOVA. RESULTS: A total of 1889 cases were analyzed. Males exhibited a significantly higher prevalence of cysts and tumors (p < 0.001). Odontogenic tumors dominated in the age group of 21-30 years, while cysts were prevalent in the age group of 11-20 years. Ameloblastoma was the most prevalent tumor (n=853; 84.1%) while dentigerous cysts were the most common cysts (n = 468; 53.5%), both demonstrating a male predilection. The mean age at presentation and site predilection of each tumor and cyst were also detailed. CONCLUSION: This study provides crucial insights into odontogenic cysts and tumors in Kenya emphasizing geographic variations, age-specific patterns, and gender disparities for more effective diagnostic and management strategies, especially in resource-limited settings, to improve outcomes and reduce associated morbidity and mortality.

Follicular Adenomatoid Odontogenic Tumor: A Case Report.

Adenomatoid odontogenic tumor (AOT) is an infrequent odontogenic tumor that typically occurs in adolescent females, usually in the anterior maxilla. There is a controversy about it being a tumor or a hamartoma. It presents clinically as a slowly progressive entity that shows a good prognosis with conservative surgical management. It shows three clinicopathological types: follicular, extrafollicular, and peripheral. This article describes a follicular variety of AOT. An 18-year-old female presented with diffuse intraoral swelling in the maxillary anterior region. An intraoral periapical radiograph (IOPA) revealed a single large pericoronal radiolucency related to the impacted right maxillary lateral incisor. Histopathological evaluation confirmed the diagnosis, and the tumor was treated surgically by enucleation.

Adenoid Ameloblastoma: The Newly Recognized Odontogenic Tumor - A Case Report.

Adenoid ameloblastoma is a newly recognized epithelial odontogenic tumor. Herein, we present the case of a 24-year-old male patient who exhibited swelling in the anterior region and right hemi-mandible. Computed tomography demonstrated the presence of a hypodense osteolytic lesion associated with an impacted tooth. Based on the clinical hypotheses of the dentigerous cyst, odontogenic keratocyst, and ameloblastoma, an incisional biopsy was performed, and the diagnosis of ameloblastoma was rendered. A surgical resection of the tumor was performed. Histopathological examination of the specimen revealed typical areas of ameloblastoma associated with ductiform structures and cell proliferation in a solid storiform pattern, features resembling those found in adenomatoid odontogenic tumor. Based on these findings, the diagnosis of adenoid ameloblastoma was rendered. The accurate diagnosis of this locally infiltrative tumor is essential due to its similarity to other odontogenic neoplasms.

Conservative enucleation for physiologic space closure in adenomatoid odontogenic tumor.

Adenomatoid odontogenic tumor (AOT) is a rare, asymptomatic, slow-growing benign tumor that can be divided into three variants: follicular, extrafollicular, and peripheral. By treating AOT using an enucleation and curettage approach, recurrence can be avoided. We report a case of a 24-year-old female who presented with a lump in the right mandibular premolar area along with diastema between displaced teeth #43 and #44 and was diagnosed with extrafollicular AOT. The patient was managed with enucleation-curettage surgery without additional bone graft procedure along with routine follow-up. A successful outcome without recurrence was achieved, and diastema closure with repositioning of the displaced teeth did not require orthodontic treatment. AOT should be managed via enucleation and curettage to obtain successful outcomes without recurrence. Spontaneous bone regeneration following enucleation can be achieved without guided bone regeneration. Also, diastema closure and repositioning of displaced teeth can occur without orthodontic interventions through physiologic drift.

Adenomatoid odontogenic tumor: A histopathologic profile of 43 cases with evidence supporting a mixed odontogenic origin.

BACKGROUND: Adenomatoid Odontogenic Tumor (AOT) accounts for 3% of all odontogenic tumors. It has been classified by WHO as an odontogenic tumor of purely epithelial origin. The current study attempts to establish the origin of the tumor along with detailed histopathological and clinicoradiographic analysis of 43 cases of AOT. MATERIAL AND METHODS: Forty-three cases were reviewed from the departmental archives for demographic data, radiographic features and histological features. Further, histopathological slides were stained with Picrosirius Red (PSR) and observed under polarised light. RESULTS: A majority of the cases were seen in the anterior jaws (76.7%), and were less than 3 cms (76.7%) in greatest dimension. Equal number of cases were of follicular and extra-follicular location while one was peripheral. Predominantly solid histological pattern was noted in 53.5%. Varied sub-patterns were observed with most cases exhibiting solid nodules and strands of tumor cells. Few cases showed melanin pigmentation. Over a third of cases (37.2%) showed dentigerous cyst like areas and one case each showed features of ossifying fibroma and focal cemento-osseous dysplasia. Tumor droplets, hyaline rings within duct-like structures, dentinoid material and osteodentin showed reddish yellow birefringence when observed under polarised microscopy post PSR staining. CONCLUSION: This study highlights the diverse histopathological variation of AOT with evidence to reclassify it as a mixed odontogenic tumor based on the polarising microscopic findings with PSR staining.

Metamorphosis of Dentigerous cyst: A case Series with Insight into Molecular Profiling.

The objective of this study was to review the clinical, radiologic, and histologic aspects of cases of dentigerous cysts metamorphosing into different entities along with comments on the molecular factors involved in the process. A series comprising 8 cases of dentigerous cysts was performed retrospectively along with a comprehensive literature review. Two cases of dentigerous cyst converting into mucous metaplasia were included, out of which one case was transformed into ameloblastoma after a year. The other two cases were reported as acanthomatous and unicystic ameloblastoma, whereas four transitioned to AOT. The complete review of cases and literature with molecular profiling concluded that the lining of dentigerous cysts has the potential for transforming into benign odontogenic tumors. Therefore, a careful clinical and histopathological examination is crucial for the correct diagnosis. Also, a thorough molecular understanding of the cystic lining is required.

Expression of anti - Apoptotic survivin in odontogenic keratocyst, adenomatoid odontogenic tumor and ameloblastoma.

Background: The process of odontogenesis is complex involving epithelial-mesenchymal interactions, along with the molecular signalling pathways triggering the initiating process. The triggering factors and cells precisely involved in the pathogenesis of odontogenic cysts and tumors are unknown. There is a vast array of biomarkers used to stain different sites, thereby helpful in diagnosing and evaluating the prognosis of these cysts and tumors. In the following study, Anti Apoptotic survivin expression patterns were assessed quantitatively in 48 samples (12 each) of Reduced Enamel Epithelium, Adenomatoid Odontogenic Tumor, Odontogenic Keratocyst and Ameloblastoma. Aim: The Aim of this study is to assess the anti-apoptotic survivin expression in Reduced Enamel Epithelium, Adenomatoid odontogenic tumour, Odontogenic Keratocyst and Ameloblastoma. Materials and Methods: The present study is carried out with 12 samples in each group. Routine hematoxylin and eosin staining was performed for confirmatory diagnosis. Later Immunohistochemistry was performed using survivin antibody. Survivin protein expression was analyzed using the parameters like location, intensity, percentage of cells positivity with survivin protein and extent of staining. With the help of Olympus BX 43 microscope, with ProgRes microscope camera, the 48 slides obtained were examined. The region of interest was selected in each slide and number of cells positively stained was counted. Data was analyzed using SPSS software version 23. Descriptive for scale data, results were analysed by using ANOVA with Chi-square test for intergroup comparison. Results: The results showed significant P value <0.05. Expression of survivin was highest in Ameloblastoma, followed by Odontogenic keratocyst, Adenomatoid odontogenic tumor, and Reduced Enamel Epithelium. Conclusion: Survivin was involved in the inhibition of apoptosis as well as the detailed understanding of the biological behaviour of odontogenic cysts and tumours, thereby increasing therapeutic approaches.

Demystifying Histologic Conundrum of Adenoid Ameloblastoma: Case Report with Literature Review.

Introduction: Odontogenic tumors encompass a heterogeneous group of lesions that range from hamartomatous lesions to malignancy. Considerable variation in histologic presentation can mislead their accurate diagnosis and categorization. Ameloblastoma is generally well understood and is easy to diagnose but there has been a constant change in the classification systems ever since Broca classified odontogenic tumors in the year 1867. Over the years, it has been modified by the World Health Organization with many additions and omissions. This dynamic change is based on the result and conclusions of molecular and genetic studies with the last modification in 2017. Case Report: We present two cases of females aged 32 and 60 years who reported with facial swellings, revealed the presence of distinct histopathological findings and were diagnosed as ameloblastoma with dentinoid or adenoid ameloblastoma. Literature search revealed dearth of distinct forms of ameloblastoma that show the formation of duct like structures and dentinoid. Conclusion: It is interesting to highlight such cases as the biological behavior is still unexplored due to paucity of relevant studies and follow up of patients. Understanding the pathogenesis and the histopathological characteristics of the newer entities will enable the prompt diagnosis, treatment plan and expanding the spectrum of the lesions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-023-03534-6.

Adenomatoid odontogenic tumor: Features of ameloblastic-like epithelial cells differentiation, secretion, and the nature of tumor cells products.

BACKGROUND: This study aimed to investigate the differentiation of ameloblastic-like cells and the nature of the secreted eosinophilic materials in adenomatoid odontogenic tumors. METHODS: We studied histological and immunohistochemical characteristics of 20 cases using: cytokeratins 14 and 19, amelogenin, collagen I, laminin, vimentin, and CD34. RESULTS: Rosette cells differentiated into ameloblastic-like cells positioned face-to-face, displaying collagen I-positive material between them. Epithelial cells of the rosettes can differentiate into ameloblastic-like cells. This phenomenon probably occurs due to an induction phenomenon between these cells. The secretion of collagen I is probably a brief event. Amelogenin-positive areas were interspersed by epithelial cells in the lace-like areas, outside the rosettes and distant from the ameloblastic-like cells. CONCLUSIONS: There are at least two types of eosinophilic material in different areas within the tumor, one in the rosette and solid areas and another in lace-like areas. The secreted eosinophilic material in the rosettes and solid areas is probably a product of well-differentiated ameloblastic-like cells. It is positive for collagen I and negative for amelogenin, whereas some eosinophilic materials in the lace-like areas are positive for amelogenin. We hypothesize that the latter eosinophilic material could be a product of odontogenic cuboidal epithelial or intermediate stratum-like epithelial cells.

Hybrid odontogenic lesions: A case series of a rare entity.

Background: The occurrence of hybrid odontogenic lesions with two or more morphologically distinct components is a rare phenomenon and poses a diagnostic challenge. We aimed to study the clinical, radiological, and pathological features and behavior of hybrid odontogenic lesions, to enhance awareness about these rare lesions. Method: Hematoxylin and Eosin slides of hybrid odontogenic lesions diagnosed between January 01, 2012 and December 31, 2020, were reviewed. Demographic and radiological information were obtained from the patient's medical records. Results: 8 cases were diagnosed with a mean age of 19.1 years and male to female ratio of 1:1.7. Involvement of mandible was more common (n = 5) as compared to maxilla (n = 3). All patients presented with swelling for an average of 9.75 months (3-25 months) duration. Bleeding, loose teeth, pain and facial asymmetry were reported in 5,3, 3, and 2 cases, respectively. Radiologically, 7 cases were well demarcated, 75% cases (n = 6) were radiolucent, and average radiological size was 4.8 cm. All patients were managed with surgery alone. 5 cases (62.5%) underwent enucleation and curettage, while local excision, en-block resection and segmental mandibulectomy were performed in 1 case each. Histologically, ossifying fibroma/cemento-ossifyiong fibroma were the most lesion, occurring in 5 cases (62%), followed by giant cell granuloma like lesions (GCG) i.e., central and peripheral giant cell granuloma (n = 3), Adenomatoid Odontogenic tumor (AOT) (n = 2), and DC (n = 2), ameloblastic fibroma (AF) (n = 1), Ameloblastoma (n = 1), calcifying odontogenic cyst (COC) (n = 1), and complex odontoma (n = 1). No evidence of recurrence was noted after 4-99 months of surgery (mean: 32.9) in cases with available data (n = 7). Long-term complaints included facial asymmetry (n = 2) and pain (n = 1). Conclusion: Most hybrid odontogenic lesions affect young females in the second decade of life and commonly show COF and OF as hybrid components. A conservative approach to management appears adequate.

Adenoid Ameloblastoma with BRAF p.V600E Mutation Revealing Ameloblastomatous Origin: A First Case Report.

BACKGROUND: Adenoid ameloblastoma (AdAM) is a frequently recurrent tumor that shows hybrid histological features of both ameloblastoma and adenomatoid odontogenic tumor (AOT). AdAM is expected to be classified as a new subtype of ameloblastoma in the next revision of the World Health Organization (WHO) odontogenic tumor classification. However, whether AdAM is a histologic variant of ameloblastoma or AOT remains unclear. To establish a new category, genetic evidence indicating the tumor category is necessary. METHODS: We present a case of a 23-year-old Japanese woman with AdAM who underwent genetic/DNA analysis for ameloblastoma-related mutation using immunohistochemical staining, Sanger sequencing, and next-generation sequencing (NGS) analyses with reliable clinicopathological evidence. RESULTS: Immunohistochemical expression of BRAF p.V600E was diffusely positive for both ameloblastoma- and AOT-like components. Sanger sequencing and NGS analyses showed missense mutations in BRAF p.V600E (c.1799T > A), a gene that is commonly altered in ameloblastomas but not in KRAS, another gene associated with AOT. CONCLUSION: This case report is the first to provide genetic evidence on the ameloblastomatous origin of AdAM with a BRAF p.V600E mutation. A larger series of AdAM groups' molecular testing is needed to aptly classify them and prognosticate the best treatment.

Calcifying odontogenic cyst with AOT-like features: a case report and literature review / Cisto odontogênico calcificante com características adenomatóides: relato de caso e revisão de literatura

Odontogenic lesions are a heterogeneous group of diseases that presents differences in their biological behavior and the occurrence of variable inductive interactions. Calcifying odontogenic cyst (COC), or Gorlin's cyst, is a well-recognized example of these lesions. We describe a case of COC with AOT-like areas and highlights its morphological diversity. A 60-year-old pheoderma man presented with a large swelling in the anterior buccal region of the mandible. Panoramic radiography revealed a well-defined, unilocular, radiolucent lesion associated with important root resorption. Complete enucleation of the lesion was performed and the histopathological findings met the criteria for the diagnosis of COC, although the cyst exhibited unusual AOT-like features. The patient has been recurrence free for 6 months after surgery. COCs with AOT-like features are rare, and reflect the multipotentiality and complexity of the inductive effects of the odontogenic epithelium with the ectomesenchyme. Enucleation seems to be the most indicated treatment, similar to classical COC (AU)

As lesões odontogênicas são um grupo heterogêneo de patologias que apresentam diferenças no seu comportamento biológico, e ocorrência de interações indutivas variáveis. O cisto odontogênico calcificante (COC), ou cisto de Gorlin, é um exemplo bem conhecido destas lesões. Descrevemos um caso de COC com áreas adenomatóides e destacamos a sua diversidade morfológica. Paciente do sexo masculino, 60 anos de idade, apresentou um aumento de volume na região anterior da mandíbula. A radiografia panorâmica revelou uma lesão bem definida, unilocular e radiolúcida associada a uma reabsorção radicular importante. A enucleação completa da lesão foi realizada e os achados histopatológicos preencheram os critérios para o diagnóstico de COC, embora o cisto exibisse características adenomatóides pouco usuais. O paciente permanece livre de recidivas durante 6 meses após a cirurgia. Os COCs com características adenomatóides são raros, e refletem a multipotencialidade e complexidade dos efeitos indutivos do epitélio odontogênico com o ectomesênquima. A enucleação parece ser o tratamento mais indicado, semelhante ao COC clássico. (AU)

An Unusual Case of Hybrid Odontogenic Tumor in Type 1 Myotonic Dystrophy Patient.

Myotonic dystrophy, also referred myotonic muscular dystrophy, is an autosomal dominant, slowly progressive, multisystem disease characterized by skeletal muscle weakness, wasting, and myotonia. A hybrid tumor of odontogenic apparatus is a lesion showing combined histopathological characteristics of two or more previously recognized odontogenic tumors and/or cysts of different categories. We, therefore, report a case of hybrid tumor (adenomatoid odontogenic tumor associated with calcifying cystic odontogenic tumor) in a myotonic dystrophic patient.

Adenoid Ameloblastoma with Dentinoid: A systematic review.

This article aimed to collectively present the demographic, clinical, radiographic and histopathological features as well as the treatment performed along with its outcome for all the cases of adenoid ameloblastoma with dentinoid (AAD) reported in scientific literature till date. Ameloblastoma and adenomatoid odontogenic tumours are the most common odontogenic neoplasms. However, AAD, a hybrid variant of the two lesions, is found to be extremely rare. The lesion comprises of characteristic histopathological features of ameloblastoma and adenomatoid odontogenic tumour and shares certain clinical characteristics with either of the entities. AAD may be considered to be present at the more aggressive end of spectrum of benign odontogenic neoplasms. Owing to the frequent tendency of the lesions 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 World Health Organization classification.

A giant adenomatoid odontogenic tumor of the mandible: A case report and literature review.

INTRODUCTION AND IMPORTANCE: An adenomatoid odontogenic tumor is a rare medical condition. Large tumor (or several) often appears in the maxillae. In a minority of cases, the tumor(s) appear in the mandible. CASE PRESENTATION: We report on a case of a 24-year-old female diagnosed with a mandibular adenomatoid odontogenic tumor, a giant tumor measuring approximately 22 × 25 × 17 cm. The tumor was located on the side of the mandible, causing facial deformity, malnutrition, and hemorrhaging. We assessed the patient's overall condition, carried out a resection of the tumor and mandible from the right condyle to the left mandibular angle, and reconstructed the mandibular defect with a fibula free flap. After the treatment, the patient was followed up for 1 year, with no recurrence detected over this period. CLINICAL DISCUSSION: Because adenomatoid odontogenic tumors are benign odontogenic lesions, which are painless and slow-growing, most are surgically removed or treated conservatively. However, the above treatment measures cannot be applied in the case of a giant tumor that causes facial deformity, destroys the entire jawbone, and has complications such as hemorrhaging and malnutrition. After the tumor resection, the defect is still significant. Accordingly, reconstruction using a microsurgical bone flap is an effective method instead. CONCLUSION: Large adenomatoid odontogenic tumors in the mandible are rare, and treatment cannot follow conventional methods. Accordingly, defect reconstruction after tumor resection is essential.

Tumor Odontogénico Adenomatoide Quístico, presentación inusual. Reporte de dos casos / Cystic Adenomatoid Odontogenic Tumor, unusual presentation. Report of two cases

RESUMEN: El tumor odontogénico adenomatoide es un tumor benigno, poco común, que corresponde al 2-7% de los tumores odontogénicos. Se presenta con mayor prevalencia en la segunda década de vida y se ubica preferentemente en maxilar anterior. Es una lesión encapsulada, no agresiva, de crecimiento lento, que puede pasar desapercibida durante años. Deriva del epitelio odontogénico, y se caracteriza histológicamente por células epiteliales dispuestas en nidos, remolinos o cordones con escaso tejido conjuntivo. Puede presentar estructuras canaliculares un patrón ductiforme, con calcificaciones y presenta cápsula. El presente estudio reporta dos casos, el primero es una mujer de 30 años y el segundo el de un hombre de 36 años, ambos con un tumor odontogénico adenomatoide ubicado en zona maxilar anterior derecha, asintomático, sin asociación con diente incluido y de presentación quística a nivel imagenológico e histopatológico. Se discuten características clínicas, radiográficas, histopatológicas y terapéuticas de los casos.

ABSTRACT: Adenomatoid odontogenic tumor is a benign, rare tumor that accounts for 2-7% of odontogenic tumors. It appears with greater prevalence in the second decade of life and is located preferentially in the anterior maxilla. It is a slow-growing, non-aggressive, encapsulated lesion that can go unnoticed for years. It is derived from the odontogenic epithelium, and is characterized histologically by epithelial cells arranged in nests, eddies, or cords with little connective tissue. It may have canalicular structures and a ductiform pattern, with calcifications and it has a capsule. The present study reports two cases, the first is a 30-year-old woman and the second is a 36-year-old man, both with an adenomatoid odontogenic tumor located in the right anterior maxillary area, asymptomatic, without association with an included tooth and cystic presentation at the imaging and histopathological levels. The clinical, radiographic, histopathological and therapeutic characteristics of the cases are discussed.

Radiological features of Adenomatoid odontogenic tumor: Report of a maxillary case and a mandibular one.

We present two cases of AOT, the first case concerns a 23-year-old patient with an AOT located in the maxilla and the second case involves a 37-year-old patient presenting an AOT with mandibular localization.

Two sides of a coin: A report of two contrasting cases of adenomatoid odontogenic tumor with unusual presentations.

This study aims to report two distinct cases of adenomatoid odontogenic tumor (AOT) with contrasting presentations. The first case involved a 12-year-old female patient with the presence of AOT in the posterior mandible extending into the mandibular ramus up till the coronoid process which is a rare reported site for AOT and the second case is of a 19-year-old male patient with the tumor in the anterior maxilla with an impacted central incisor. Both cases were successfully managed via surgical enucleation and are under regular follow-ups without any complication. The contrasting nature of the two clinical presentations with the same pathologic entity is reported here. Though AOT has been rarely reported extending into the mandibular ramus, a maxillofacial surgeon should be more circumspect of this pathology while dealing with benign swellings of the mandibular posterior region.