Ameloblastic fibroma (AF) is a rare benign odontogenic tumour first described by Kruse in 1891. Although reported in a wide age range, most of the cases are seen in the first two decades of life with majority of cases being diagnosed before the age of 20 years. There are reported variations in the histopathological presentation of ameloblastic fibroma. In this case report, we present a case of ameloblastic fibroma with extensive dentinoid formation involving the mandible in an 8-year-old male patient which clinically presented as an aggressive lesion.

Ameloblastic fibrosarcoma (AFS) is considered a malignant progression resulting from dysplastic changes in an ameloblastic fibroma (AF). Both tumors are extremely rare, with only a few cases reported in the scientific literature. Notably, BRAF mutations have been identified in ameloblastomas, suggesting a connection between ameloblastic morphology and BRAF mutations, as AF is believed to be the precursor neoplasm leading to AFS. In this study, we present a case of AFS in a 25-year-old male. The tumor tissue underwent molecular analysis, specifically next-generation sequencing (NGS) using the Oncomine Comprehensive Assay v3 System. The analysis revealed pathogenic mutations in TP53 and RB genes, as well as copy number gains in NTRK1, MDM4, and BRAF. Additionally, we provide a summary of the literature\'s findings from the analysis of 107 previously reported AFS cases. Our findings suggest the existence of a molecularly distinct subtype, emphasizing the importance of comprehensive molecular testing for these patients.

UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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).
UNASSIGNED: 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.

Ameloblastic fibroma is a rare mixed odontogenic benign tumor that can occur in either mandible or maxilla but mostly it is found in posterior region of mandible. It can present either peripherally or centrally with a majority of the cases predominantly occurring in first two decades of life and mostly affects male patients. It is characterized by epithelial islands and cords submerged in ectomesenchyme that bear resemblance to the dental papilla and enamel organ but without actual hard tissue formation. Ameloblastic fibroma is a rare odontogenic tumor consisting of neoplastic epithelial and mesenchymal tissues. Recent reports have suggested that this lesion has the potential for high recurrence (18%) and greater chances of recurrent Ameloblastic fibroma transforming into Ameloblastic fibrosarcoma (45%). A 34-year-old male patient presented with pain and swelling in right mandibular posterior region. Intraorally expansion of buccal cortical plate with tenderness over swelling was present. Extraoral examination revealed facial asymmetry on right side. In view of imaging and clinical findings, provisional diagnosis of Odontogenic Keratocyst or Recurrent Ameloblastoma was considered. After obtaining informed consent and general systemic evaluation, the lesion was enucleated under general anesthesia and biopsied which confirmed the diagnosis of Ameloblastic fibroma. Ameloblastic fibroma is a mixed odontogenic tumor composed of odontogenic ectomesenchyme resembling dental papilla with epithelial strands and nests similar to the dental lamina and enamel organ, but with no dental hard tissue formation. Odontogenic tumors, Ameloblasts, Ameloblastoma, Jaw neoplasm.

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Ameloblastic fibrosarcoma (AFS) is an extremely rare malignant odontogenic tumor. It is composed of benign odontogenic epithelium, resembling that of ameloblastoma, and a mesenchymal part exhibiting features of fibrosarcoma. The development of this lesion in the jaws is either de novo or from preexisting ameloblastic fibroma which has been well documented. The most commonly affected site within the jaw is the posterior mandible. These tumors show local aggressiveness and a high tendency to recur. We present a case of a 33-year-old female patient with swelling of the right posterior mandible for 2 months and progressive paresthesia of the same region for the past 6 months. Patient\'s history revealed undergoing surgical enucleation for ameloblastic fibroma before a year in the same region as current swelling. Examination of the swelling revealed an ulceroprolifeartive Growth of 6 × 4.5 cm extending from premolar to molar region. Primary investigation involved biopsy of the swelling, which was reported as sarcoma for which resection of the right hemimandible and selective neck dissection was performed. Following surgery, the final histopathology report of the resected specimen was reported to be AFS. One year after the surgical procedure, the patient is clinically and radiologically disease-free. Considering the aggressive nature of these tumors, it is vital to give an accurate diagnosis through biopsy, which is considered as gold standard diagnostic evidence, so that the surgeon plans the appropriate therapeutic decision. Knowledge of this rare entity and its histologic features as opposed to the more common benign counterparts such as ameloblastoma or ameloblastic fibroma is crucial as the latter involves a conservative treatment approach while the former can only be treated through aggressive resections.

An ameloblastic fibroma with formation of dental hard tissues, which the classical name is ameloblastic fibro-odontoma (AFO), is a rare type of mixed odontogenic tumor. An 8-year-old boy was diagnosed with AFO, with an inhomogeneous high signal within the lesion shown by T2-weighted magnetic resonance imaging (MRI). Computed tomography (CT) imaging revealed a unilocular low CT value area of 24 × 19 × 26 mm with buccolingual bony expansion and cortical bone thinning on the left side of the mandible including the crown of the mandibular left second molar. In addition, multiple calcified bodies were detected within the lesion, one of which had a CT value of approximately 2200 HU, equivalent to that of enamel. MRI indicated the lesion to be sized 24 × 19 × 25 mm along with buccolingual bony expansion in the left side of the mandible. Additionally, the lesion showed an internal inhomogeneous high signal, while a portion had an especially high signal in T2-weighted images. That particularly high signal area coincided with the nodular growth area of mucus-rich mesenchymal components without the epithelial component in histopathology findings. The particularly high signal revealed by T2-weighted imaging could be attributed to the mucus-rich component. MRI was found useful for revealing differences in the internal histopathological properties of an AFO in our patient.

A 19-year-old male patient reported to dental OPD of our institution with a swelling in the posterior part of the mandible on the left side. The patient gave a history of gradual increase in the size of swelling for 7 years. The patient also had a radiograph and histopathology slides from his previous dental visit at another facility. The radiograph revealed a well-circumscribed radiolucency with an impacted tooth (38). Histopathology slides showed features of an ameloblastic fibroma (AF). The patient had deferred the treatment for 5 years since he was young and reported to our OPD due to increase in the size of the swelling over the past few weeks. The present radiographs revealed radiolucency with radiopacity. Excisional biopsy was performed and the histopathological examination revealed an Ameloblastic fibro odontoma. This case report is to document and highlight the possible progression of AF to Ameloblastic fibro-odontoma.

BACKGROUND: Ameloblastic fibromas and ameloblastic fibrosarcomas are rare odontogenic tumors, and controversy exists in the classification of cases presenting hard-tissue production: Ameloblastic fibrodentinoma (AFD) and ameloblastic fibro-odontoma (AFO). These cases are currently considered \"developing odontomas\" (hamartomatous lesions).
OBJECTIVE: To analyze the clinicopathologic features of these lesions and discuss the changes in the 2017 World Health Organization classification.
METHODS: An electronic literature search was performed in the PubMed/MEDLINE database. An electronic search of the English language literature was performed and last updated in September 2020 in the PubMed/MEDLINE database using the following terms: \"ameloblastic fibroma\", \"ameloblastic fibrodentinoma\", \"ameloblastic fibro-odontoma\", \"ameloblastic sarcoma\", \"ameloblastic fibrosarcoma\", \"ameloblastic fibrodentinosarcoma\", \"ameloblastic fibroodontosarcoma\" and \"odontogenic carcinosarcoma\". The inclusion criteria were odontogenic tumor series, case reports and systematic reviews that provided sufficient clinical, radiological and microscopic documentation to confirm the diagnosis.
RESULTS: The database search strategy resulted in 947 papers. Articles focusing on other topics, articles that were not in English, duplicate articles, and articles without fulfilling the inclusion criteria were excluded. Finally, 96 publications were included in this review to describe and discuss the main features of the searched entities. Several aspects of AFO and AFD, such as biological behavior, age of occurrence, amount of hard tissue, and potential for malignant transformation into odontogenic sarcomas, support the neoplastic nature in most of the reported cases. Considering the clinical, radiographic, histopathological and molecular characteristics of odontogenic lesions with hard tissue production, we suggest that these types of lesions should continue to be recognized as odontogenic tumors by maintaining the classically used terms.
CONCLUSIONS: This recommendation will be relevant for future clinical, microscopic, and molecular studies to better understand the biology of these interesting odontogenic tumors.

Ameloblastic fibro-odontoma (AFO) is a relatively rare, benign noninvasive mixed odontogenic neoplasm derived from epithelial and ectomesenchymal elements of the dental tissues. It usually presents with a mean age of 11.5 years and in the posterior segment of the mandible. It is extremely rare in the posterior maxilla. Although the latest WHO edition classified AFO as developing odontoma, here we present a locally aggressive AFO in a 21-year-old male involving the posterior maxilla and sinus with bone destruction. The patient presents with a two-year history of slowly progressive left facial swelling with malodorous drainage. The CT scan revealed a 5.5 x 4.3 cm well-circumscribed expansile mass with mixed attenuation and peripheral calcification occupying the left maxilla and sinus with bone destruction of the hard palate and orbital rim. According to the literature, most of the AFO cases were treated adequately through a conservative approach with just enucleation or surgical curettage. To our knowledge, our case is the first case treated aggressively with left maxillectomy, palatectomy, and reconstruction surgery because of its radiologic findings, which suggested a locally invasive neoplasm. Histologically, the specimen showed a mixture of proliferative epithelial, mesenchymal tissue elements, and variable amounts of mineralized deposits consisting of enamel matrix and dentinoid deposits, and the final diagnosis was AFO. In conclusion, we present a rare case of AFO with an unusual aggressive presentation, age group, and site involved. The radiographic, histopathologic features, and therapeutic approaches of this unusual locally aggressive tumor are presented with the review of relevant literature.