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Journal of Personalized Medicine Jan 2022Ameloblastoma is the most common benign odontogenic neoplasm, but with an aggressive behavior and a high recurrence rate. Nowadays wide surgical resection is the current...
Ameloblastoma is the most common benign odontogenic neoplasm, but with an aggressive behavior and a high recurrence rate. Nowadays wide surgical resection is the current recommended treatment, which can cause further loss of function and esthetics. Recent studies point to the stem/progenitor cells as both initiators and propagators of the tumors. Elucidation of the cellular and molecular mechanisms underlying the tumor stem cells is of broad interest for understanding tumorigenesis and for developing effective targeted therapies. SRY related HMG box gene 2 (SOX2) is a transcription factor that plays important roles in development, stem cell renewal, and cancer formation. Few studies have revealed increased SOX2 expression in atypical ameloblastoma and ameloblastic carcinoma. For the development of personalized medicine for ameloblastoma, biomarkers that provide prognostic or predictive information regarding a tumor's nature or its response to treatment are essential. Thus, in this study, we aimed to study if SOX2-positive cells exist in ameloblastomas and their correlation with the clinicopathologic parameters. Our data suggested BRAF(V600E) mutation might contribute to the expansion of SOX2-positive cells. The identification of BRAF(V600E) mutation and the amplification of SOX2-positive cells in ameloblastomas imply the possible benefit of applying BRAF and SOX2 inhibitors in recurrent and un-resectable ameloblastomas.
PubMed: 35055392
DOI: 10.3390/jpm12010077 -
Ear, Nose, & Throat Journal Jul 2018Ameloblastoma is a histologically benign but locally aggressive tumor of the jaws. We conducted a retrospective cohort study to review the clinical, radiologic, and...
Ameloblastoma is a histologically benign but locally aggressive tumor of the jaws. We conducted a retrospective cohort study to review the clinical, radiologic, and pathologic features of patients with ameloblastoma of the mandible and maxilla and to report the outcomes of treatment. Our study population was made up of a series of 30 consecutively presenting patients-15 men and 15 women, aged 19 to 81 years (median: 61.5)-who had undergone their primary treatment of ameloblastoma of the mandible or maxilla at Memorial Sloan Kettering Cancer Center from January 1987 through December 2012. In addition to demographic data, we compiled information on clinical characteristics, imaging findings, the type of surgery, surgical margins, adjuvant treatments, histologic patterns, length of follow-up, time to recurrence, treatment of recurrence, and factors that had an influence on recurrence. All but 2 patients with negative margins were cured. Favorable outcomes were associated with the administration of adjuvant postoperative radiotherapy for patients with positive margins and a repeat resection for patients with recurrences. Complete excision with negative margins, however, remains the gold standard for curative treatment.
Topics: Adult; Aged; Aged, 80 and over; Ameloblastoma; Antineoplastic Agents; Chemotherapy, Adjuvant; Female; Humans; Male; Mandibular Neoplasms; Maxillary Neoplasms; Middle Aged; Postoperative Period; Retrospective Studies; Treatment Outcome; Young Adult
PubMed: 30036443
DOI: 10.1177/014556131809700704 -
Scientific Reports Oct 2020Ameloblastomas are epithelial odontogenic tumours that, although benign, are locally invasive and may exhibit aggressive behaviour. In the tumour microenvironment, the...
Ameloblastomas are epithelial odontogenic tumours that, although benign, are locally invasive and may exhibit aggressive behaviour. In the tumour microenvironment, the concentration of oxygen is reduced, which leads to intratumoral hypoxia. Under hypoxia, the crosstalk between the HIF-1α, MMP-2, VEGF, and VEGFR-2 proteins has been associated with hypoxia-induced angiogenesis, leading to tumour progression and increased invasiveness. This work showcases 24 ameloblastoma cases, 10 calcifying odontogenic cysts, and 9 dental follicles, used to investigate the expression of these proteins by immunohistochemistry. The anti-HIF-1α, anti-MMP-2, anti-VEGF, and anti-VEGFR-2 primary antibodies are used in this work. The results have been expressed by the mean grey value after immunostaining in images acquired with an objective of 40×. The ameloblastoma samples showed higher immunoexpression of HIF-1α, MMP-2, VEGF, and VEGFR-2 when compared to the dental follicles and calcifying odontogenic cysts. Ameloblastomas show a higher degree of expression of proteins associated with intratumoral hypoxia and proangiogenic proteins, which indicates the possible role of these proteins in the biological behaviour of this tumour.
Topics: Ameloblastoma; Biomarkers; Dental Sac; Disease Progression; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Immunohistochemistry; Matrix Metalloproteinase 2; Neoplasm Invasiveness; Neovascularization, Pathologic; Odontogenic Tumors; Prognosis; Tumor Microenvironment; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-2
PubMed: 33067558
DOI: 10.1038/s41598-020-74693-7 -
Journal of Maxillofacial and Oral... Mar 2022Ameloblastoma (AMBL) is an odontogenic tumor, considered to be benign, but aggressive, whose principal risk is a recurrence. The growth can be enormous, and it can... (Review)
Review
BACKGROUND
Ameloblastoma (AMBL) is an odontogenic tumor, considered to be benign, but aggressive, whose principal risk is a recurrence. The growth can be enormous, and it can extend into the intracranial compartment with serious consequences.
PURPOSE
The intracranial involvement of AMBL is rare, and it may require an extensive surgery. Although it is a rare condition for the neurosurgeon to treat, knowing this condition can lead to a significant increase in survival for these patients.
METHODS
A case of a 56-year-old woman presented with a history of recurrent left maxilla AMBL with intracranial extension and dural involvement of the anterior and medial cranial fossa is reported, followed by a systematic review of the literature with the aim to identify the best surgical treatment.
RESULTS
A total of 32 cases were included in the qualitative analysis. Management is varied and often not described, resulting in an almost complete lack of information and indications for treatment. Radical surgery tends to yield the best outcomes, and it is recommended to have adequate surgical margins when possible.
CONCLUSIONS
Intracranial involvement from AMBL compartment is an uncommon manifestation of this rare pathology, but which deserves to be treated in a multidisciplinary way in order to ensure maximum surgical radicality. Recurrence reflects failure of the primary surgical resection. If recurrence is the major consideration, surgeons are encouraged to select radical surgery. Whenever a follicular-type maxillary AMBL is diagnosed, it is advisable to check for intracranial spreading and distant metastases during follow-up.
PubMed: 35400903
DOI: 10.1007/s12663-021-01643-9 -
National Journal of Maxillofacial... Aug 2022Ameloblastic fibrosarcoma (AFS) is an extremely rare malignant odontogenic tumor. It is composed of benign odontogenic epithelium, resembling that of ameloblastoma, and...
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.
PubMed: 36393933
DOI: 10.4103/njms.NJMS_100_20 -
Frequency of Odontogenic Tumors: A Single Center Study of 1089 Cases in Japan and Literature Review.Head and Neck Pathology Jun 2022Several attempts have been made to classify odontogenic tumors; however, the need for a uniform international classification system led the World Health Organization... (Review)
Review
Several attempts have been made to classify odontogenic tumors; however, the need for a uniform international classification system led the World Health Organization (WHO) to present a classification of odontogenic tumors in 1971. We aimed to evaluate the number and types of odontogenic tumors examined at the Tokyo Dental College Hospital in Japan to determine the frequency and types of odontogenic tumors, based on the 2017 WHO classification system, as this information has not been reported previously in Japan. We also compared the results of our evaluation with those reported in previous studies. We conducted a clinicopathological evaluation of odontogenic tumors examined at the Tokyo Dental College Hospital between 1975 and 2020. This included an analysis of 1089 cases (malignant, n = 10, 0.9%; benign, n = 1079, 99.1%) based on the 2017 World Health Organization Classification of Head and Neck Tumors. We identified 483 (44.3%), 487 (44.7%), and 109 (10.0%) benign epithelial odontogenic, mixed odontogenic, and mesenchymal tumors, respectively. The most common tumor types were odontoma (42.5%) and ameloblastoma (41.9%). Of the 1089 cases, 585 (53.7%) and 504 (46.3%) were male and female patients, respectively. Ameloblastoma and ameloblastic fibroma occurred more commonly in male patients, whereas odontogenic fibroma and cemento-ossifying fibroma affected female patients primarily. The age at diagnosis ranged from three to 87 (mean, 29.05) years. In 319 (29.3%) patients, the age at diagnosis ranged from 10 to 19 years. Ameloblastoma and odontoma were the most common tumor types among patients in their 20s and those aged 10-19 years, respectively. In 737 (67.7%) and 726 (66.7%) patients, the tumors were located in the mandible and posterior region, respectively. Ameloblastoma was particularly prevalent in the posterior mandible. Odontogenic tumors are rare lesions and appear to show a definite geographic variation.
Topics: Ameloblastoma; Female; Fibroma, Ossifying; Humans; Japan; Male; Odontogenic Tumors; Odontoma; Retrospective Studies
PubMed: 34716904
DOI: 10.1007/s12105-021-01390-w -
Scientific Reports Dec 2021Ameloblastoma is a benign, epithelial cancer of the jawbone, which causes bone resorption and disfigurement to patients affected. The interaction of ameloblastoma with...
Ameloblastoma is a benign, epithelial cancer of the jawbone, which causes bone resorption and disfigurement to patients affected. The interaction of ameloblastoma with its tumour stroma drives invasion and progression. We used stiff collagen matrices to engineer active bone forming stroma, to probe the interaction of ameloblastoma with its native tumour bone microenvironment. This bone-stroma was assessed by nano-CT, transmission electron microscopy (TEM), Raman spectroscopy and gene analysis. Furthermore, we investigated gene correlation between bone forming 3D bone stroma and ameloblastoma introduced 3D bone stroma. Ameloblastoma cells increased expression of MMP-2 and -9 and RANK temporally in 3D compared to 2D. Our 3D biomimetic model formed bone nodules of an average surface area of 0.1 mm and average height of 92.37 [Formula: see text] 7.96 μm over 21 days. We demonstrate a woven bone phenotype with distinct mineral and matrix components and increased expression of bone formation genes in our engineered bone. Introducing ameloblastoma to the bone stroma, completely inhibited bone formation, in a spatially specific manner. Multivariate gene analysis showed that ameloblastoma cells downregulate bone formation genes such as RUNX2. Through the development of a comprehensive bone stroma, we show that an ameloblastoma tumour mass prevents osteoblasts from forming new bone nodules and severely restricted the growth of existing bone nodules. We have identified potential pathways for this inhibition. More critically, we present novel findings on the interaction of stromal osteoblasts with ameloblastoma.
Topics: Ameloblastoma; Animals; Bone Resorption; Core Binding Factor Alpha 1 Subunit; Gene Expression; Humans; Jaw Neoplasms; Matrix Metalloproteinase 2; Neoplasm Invasiveness; Osteoblasts; Osteogenesis; RANK Ligand; Rats; Stromal Cells; Tissue Engineering; Tumor Cells, Cultured; Tumor Microenvironment
PubMed: 34916549
DOI: 10.1038/s41598-021-03484-5 -
SA Journal of Radiology 2023In developing countries, many diagnosed cases of ameloblastoma (AB) have a significant delay in receiving treatment because of patient factors and healthcare facility...
BACKGROUND
In developing countries, many diagnosed cases of ameloblastoma (AB) have a significant delay in receiving treatment because of patient factors and healthcare facility constraints.
OBJECTIVES
The radiologic progression of ABs with delayed treatment was analysed using panoramic radiographs and cone-beam computed tomography imaging.
METHOD
Histopathologically confirmed cases of AB with follow-up radiographs indicating no treatment were retrospectively reviewed over a study period of 10 years. Fifty-seven cases with 57 initial and 107 follow-up radiographs were included. Each follow-up radiograph was analysed for changes in borders, locularity, effects on surrounding structures and lesion size.
RESULTS
There was a general increase in poorly-demarcated lesions, with seven cases transforming from an initial unilocular to a multilocular appearance. At follow-up, there was an increase in cortical thinning and cortical destruction. Ameloblastomas presented with a three-fold increase in average size from the initial to follow-up visits. Regression analysis showed a statistically significant relationship between lesion duration and length ( = 0.001). A statistically significant relationship existed between duration and overall lesion dimensions when only the first and last observations per patient were used ( = 0.044).
CONCLUSION
Considering the aggressive nature and unlimited growth potential, ABs with delayed treatment may show extensive growth, complicating their eventual management.
CONTRIBUTION
This study aimed to raise awareness of the importance of the timeous management of patients with AB by highlighting the detrimental effects of delayed treatment.
PubMed: 37292423
DOI: 10.4102/sajr.v27i1.2668 -
Clinical and Experimental Dental... Feb 2021Ameloblastoma is a benign, locally aggressive odontogenic tumor with high recurrence rates. Matrix metalloproteinases (MMPs) mediate extracellular integrity in normal...
OBJECTIVES
Ameloblastoma is a benign, locally aggressive odontogenic tumor with high recurrence rates. Matrix metalloproteinases (MMPs) mediate extracellular integrity in normal and pathological conditions, and exert multiple functions coordinating inflammation and tumor progression. E-cadherin and beta-catenin are adherence junction molecules in cell-to-cell connections. We investigated the involvement of MMP-7, -8, -9, E-cadherin, and beta-catenin in ameloblastoma and the surrounding extracellular matrix.
MATERIAL AND METHODS
Our material consisted of 30-34 tissue samples from ameloblastoma patients of Helsinki University Hospital. We used immunohistochemistry to detect the expression of the biomarkers. Two oral pathologists independently scored the immunoexpression intensities and statistical calculations were made based on the results.
RESULTS
E-cadherin expression was weaker in the maxillary than in mandibular ameloblastomas. Beta-catenin was expressed in the ameloblastoma cell membranes. We detected MMP-8 and -9 expression in polymorphonuclear neutrophils in the extracellular area and these MMPs correlated positively with each other. Osteoclasts lining bone margins and multinuclear giant cells expressed MMP-9. Neither MMP-8 nor MMP-9 immunoexpression could be detected in ameloblastoma cells. MMP-7 expression was seen in some apoptotic cells.
CONCLUSION
The fact that E-cadherin immunoexpression was weaker in maxillary compared to mandibular ameloblastomas might associate to earlier recurrences. It promotes the idea of mandibular and maxillary ameloblastoma exerting differences in their biologies. We detected MMP-8 and -9 in polymorphonuclear neutrophils which relates to these MMPs participating in extracellular remodeling through a mild inflammatory process. Bone degradation around ameloblastoma may be due to MMP-9 in osteoclasts but this phenomenon might be an independent process and needs further investigations.
Topics: Ameloblastoma; Cadherins; Humans; Matrix Metalloproteinase 7; Matrix Metalloproteinase 8; Matrix Metalloproteinase 9; beta Catenin
PubMed: 32985799
DOI: 10.1002/cre2.331 -
Archives of Pathology & Laboratory... Jun 2014Some dental abnormalities have environmental causes. Other odontogenic alterations are idiopathic and may have hereditary etiologies. Investigations of these conditions... (Review)
Review
CONTEXT
Some dental abnormalities have environmental causes. Other odontogenic alterations are idiopathic and may have hereditary etiologies. Investigations of these conditions are ongoing.
OBJECTIVE
To provide a discussion of developmental odontogenic abnormalities and benign odontogenic overgrowths and neoplasms for which genetic alterations have been well demonstrated and well documented.
DATA SOURCES
Relevant peer-reviewed literature.
CONCLUSIONS
The understanding of benign odontogenic lesions at a molecular level is rather well developed for some lesions and at the initial stages for many others. Further characterization of the molecular underpinnings of these and other odontogenic lesions would result in an enhanced comprehension of odontogenesis and the pathogenesis of a variety of odontogenic aberrations. These advancements may lead to better prevention and treatment paradigms and improved patient outcomes.
Topics: Ameloblastoma; Amelogenesis Imperfecta; Anodontia; Dentin Dysplasia; Dentinogenesis Imperfecta; Humans; Mutation; Odontogenesis; Odontogenic Cysts; Odontogenic Tumors; Odontoma; Tooth Abnormalities; Tooth, Supernumerary
PubMed: 24878015
DOI: 10.5858/arpa.2013-0057-SA