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Head and Neck Pathology Jun 2020Claudins are integral to the structure and function of tight junctions. Altered claudin expression has been shown to affect disease behavior and patient prognosis in...
Claudins are integral to the structure and function of tight junctions. Altered claudin expression has been shown to affect disease behavior and patient prognosis in various neoplasms. The objectives of this study were to analyze the claudin-1, -4 and -7 expression in odontogenic tumors and characterize their expression pattern in distinct tumor cell types in relation to the recurrence potential. Sixty-nine cases of odontogenic tumors, including 43 ameloblastomas (AM), 17 adenomatoid odontogenic tumors (AOT), 6 ameloblastic fibromas (AF) and 3 ameloblastic carcinomas (AC) were investigated for claudin-1, -4 and -7 expression immunohistochemically. The staining was analyzed semi-quantitatively and categorized into 4 levels, based on the percentage of positively stained neoplastic epithelial cells. Claudin-1 was expressed in all AOT and AF cases, whereas most AC (66.7%) showed no expression. The claudin-1 staining was moderate-to-intense in the odontogenic epithelium of AF. In contrast, its staining of ameloblast-like cells and stellate reticulum-like cells in AM was weak. Claudin-7 expression was noted in all tumor types studied, while the expression of claudin-4 was limited and mainly localized in the squamous differentiated cells of AM and AC. AM showed significantly higher claudin-4, but lower claudin-7 expression than AOT. In addition, AC showed diminished claudin-1 immunoreactivity, compared to AOT. Low claudin-1 expression in AM was significantly associated with the increased clinical recurrence. The loss of claudin-1 may underlie the locally invasive nature of AM.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Child; Claudins; Female; Humans; Male; Middle Aged; Odontogenic Tumors; Young Adult
PubMed: 31473941
DOI: 10.1007/s12105-019-01072-8 -
Genes Aug 2023Stem cells have been associated with self-renewing and plasticity and have been investigated in various odontogenic lesions in association with their pathogenesis and... (Review)
Review
BACKGROUND
Stem cells have been associated with self-renewing and plasticity and have been investigated in various odontogenic lesions in association with their pathogenesis and biological behavior. We aim to provide a systematic review of stem cell markers' expression in odontogenic tumors and cysts.
METHODS
The literature was searched through the MEDLINE/PubMed, EMBASE via OVID, Web of Science, and CINHAL via EBSCO databases for original studies evaluating stem cell markers' expression in different odontogenic tumors/cysts, or an odontogenic disease group and a control group. The studies' risk of bias (RoB) was assessed via a Joanna Briggs Institute Critical Appraisal Tool. Meta-analysis was conducted for markers evaluated in the same pair of odontogenic tumors/cysts in at least two studies.
RESULTS
29 studies reported the expression of stem cell markers, e.g., SOX2, OCT4, NANOG, CD44, ALDH1, BMI1, and CD105, in various odontogenic lesions, through immunohistochemistry/immunofluorescence, polymerase chain reaction, flow cytometry, microarrays, and RNA-sequencing. Low, moderate, and high RoBs were observed in seven, nine, and thirteen studies, respectively. Meta-analysis revealed a remarkable discriminative ability of SOX2 for ameloblastic carcinomas or odontogenic keratocysts over ameloblastomas.
CONCLUSION
Stem cells might be linked to the pathogenesis and clinical behavior of odontogenic pathologies and represent a potential target for future individualized therapies.
PubMed: 37761874
DOI: 10.3390/genes14091735 -
Frontiers in Oral Health 2021Malignant odontogenic tumours (MOTs) arise either from the tooth forming tissues, their developmental residues or from existing odontogenic epithelial or mesenchymal...
Malignant odontogenic tumours (MOTs) arise either from the tooth forming tissues, their developmental residues or from existing odontogenic epithelial or mesenchymal neoplasms in the jaws. Their management requires extensive surgery due to their infiltrative nature and risk of metastasis. There is a need to understand the clinical and pathological features of MOTs to inform both treatment algorithms and prognostication. This is an area of diagnostic pathology which presents substantial difficulties in diagnosis, compounded by inconsistent use of terminology. Thus, this systematic review aimed to describe the clinical and pathological features of MOTs with a view to consolidating the literature and defining problematic areas in diagnosis and classification. An electronic database search was conducted in Web of Science, PubMed/Medline, and Embase. Additionally, the grey literature and reference lists of selected papers searched for completeness. Nine hundred and sixty articles were initially identified. Following removal of duplicates and application of inclusion/exclusion criteria, 312 articles were included for qualitative analysis. The 312 articles encompassed a total of 507 patients with most lesions located within the mandible (74.3%). The most common first histological diagnosis was ameloblastic carcinoma (25.7% of all diagnoses), but there is considerable variation in how and when various diagnostic terms are used, and several misdiagnoses were reported. An initial benign diagnosis was made in 24.7% of patients, followed by a later malignant diagnosis and in this sub-group, the most common benign first diagnosis was ameloblastoma (42.4%). Cervical lymph nodes were the most common site of metastasis (9.3% of patients). With respect to distant metastasis (DM), the lungs were the most common organ affected (11.2% of DM patients) with metastasising ameloblastoma the most commonly reported tumour which metastasised to the lungs. Overall, 26.8% of patients developed recurrence. Overall, the quality of the literature on MOTs is poor. This review of the literature has highlighted variations in diagnostic terms and criteria which has resulted in areas of confusion with potential for misdiagnosis. This consolidation of primary data has identified key areas for targeted research including further discussion on the malignant potential of ameloblastoma.
PubMed: 35048074
DOI: 10.3389/froh.2021.775707 -
JPRAS Open Sep 2019Ameloblastic fibrosarcoma (AFS) is a rare malignant odontogenic tumour classified by the WHO (1992) as an odontogenic sarcoma and defined as "a neoplasm with a similar...
Ameloblastic fibrosarcoma (AFS) is a rare malignant odontogenic tumour classified by the WHO (1992) as an odontogenic sarcoma and defined as "a neoplasm with a similar structure to ameloblastic fibroma (AF) but in which the ectomesenchymal component shows the features of a sarcoma." The first report of AFS was published by Heath in 1887. AFS and related lesions are less frequently diagnosed than odontogenic carcinomas. Approximately two-thirds of AFSs seem to arise de novo, but others have developed in recurrent AF, in which the ectomesenchymal cells retain their embryonic appearance and develop malignant characteristics. We report a rare case of an aggressive odontogenic neoplasm, the incisional biopsy of which showed the features of AF, while the excisional biopsy revealed the features of malignancy, suggestive of AFS. The purpose of this report is to discuss the diagnostic difficulties, whether AFS is truly an extremely rare tumour as reported earlier and, lastly, should the treatment protocols of AFs be revised, as 44% of AFSs arise from recurrent AFs.
PubMed: 32158887
DOI: 10.1016/j.jpra.2019.05.001 -
Virchows Archiv : An International... Mar 2018The latest (4th) edition of the World Health Organization Classification of Head and Neck tumours has recently been published with a number of significant changes across... (Review)
Review
The latest (4th) edition of the World Health Organization Classification of Head and Neck tumours has recently been published with a number of significant changes across all tumour sites. In particular, there has been a major attempt to simplify classifications and to use defining criteria which can be used globally in all situations, avoiding wherever possible the use of complex molecular techniques which may not be affordable or widely available. This review summarises the changes in Chapter 8: Odontogenic and maxillofacial bone lesions. The most significant change is the re-introduction of the classification of the odontogenic cysts, restoring this books status as the only text which classifies and defines the full range of lesions of the odontogenic tissues. The consensus group considered carefully the terminology of lesions and were concerned to ensure that the names used properly reflected the best evidence regarding the true nature of specific entities. For this reason, this new edition restores the odontogenic keratocyst and calcifying odontogenic cyst to the classification of odontogenic cysts and rejects the previous terminology (keratocystic odontogenic tumour and calcifying cystic odontogenic tumour) which were intended to suggest that they are true neoplasms. New entities which have been introduced include the sclerosing odontogenic carcinoma and primordial odontogenic tumour. In addition, some previously poorly defined lesions have been removed, including the ameloblastic fibrodentinoma, ameloblastic fibro-odontoma, which are probably developing odontomas, and the odontoameloblastoma, which is not regarded as an entity. Finally, the terminology "cemento" has been restored to cemento-ossifying fibroma and cemento-osseous dysplasias, to properly reflect that they are of odontogenic origin and are found in the tooth-bearing areas of the jaws.
Topics: Bone Neoplasms; Head and Neck Neoplasms; Humans; Odontogenic Tumors; Odontoma; Terminology as Topic; World Health Organization
PubMed: 28674741
DOI: 10.1007/s00428-017-2182-3 -
Journal of Pharmacy & Bioallied Sciences Apr 2024Ameloblastic carcinoma is a rare malignant odontogenic tumor that is further classified into being primary or secondary arising from a preexisting benign ameloblastoma....
Ameloblastic carcinoma is a rare malignant odontogenic tumor that is further classified into being primary or secondary arising from a preexisting benign ameloblastoma. It affects the mandible in two thirds of the patients. There is no standard treatment protocol for this lesion but radicalsurgical excision with or without radiotherapy is reported in the majority of cases. In this paper, we present a case of a 22 year old male diagnosed with Ameloblastic carcinoma of the mandible with a clinical course of typical aggressiveness and extensive destruction. Histopathological examination of the incised biopsy showed a parakeratinized stratified squamous epithelium with underlying fibrous connective tissue stroma. The stroma is highly myxomatous and exhibits islands of odontogenic epithelium and chronic inflammatory cell infiltrates. Interlacing strands of odontogenic epithelium shows stellate reticulum-like cells and occasional areas of squamous metaplasia with cellular and nuclear pleomorphism. In addition, mitotic figures were noted. With the correlation of clinical, radiographic, and histological features, the lesion is diagnosed as ameloblastic carcinoma. The lesion was surgical excised and post-treatment follow-up for 6 months revealed no recurrence of the malignancy.
PubMed: 38882877
DOI: 10.4103/jpbs.jpbs_1204_23 -
Journal of Comparative Pathology Aug 2022A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8 cm in diameter, covered the upper left...
A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8 cm in diameter, covered the upper left intermediate and corner incisor teeth (nos. 602 and 603 according to the modified Triadan system) and radiographic examination revealed displacement and lysis of the incisors. Histologically, the tumour was composed of a dense proliferation of spindle-shaped cells and neoplastic odontogenic epithelial cells arranged in island, follicular, plexiform or sheetlike patterns. The spindle-shaped cells were immunopositive for cytokeratins AE1/AE3, 5/6, 14 and 19. The Ki-67 index was 32.6% in the spindle cell component. Based on the histological and immunohistochemical findings, the tumour was diagnosed as spindle cell ameloblastic carcinoma.
Topics: Ameloblastoma; Animals; Carcinoma; Horse Diseases; Horses; Male
PubMed: 36008038
DOI: 10.1016/j.jcpa.2022.05.006 -
The Molecular Pathology of Odontogenic Tumors: Expanding the Spectrum of MAPK Pathway Driven Tumors.Frontiers in Oral Health 2021Odontogenic tumors comprise a heterogeneous group of lesions that arise from the odontogenic apparatus and their remnants. Although the etiopathogenesis of most... (Review)
Review
Odontogenic tumors comprise a heterogeneous group of lesions that arise from the odontogenic apparatus and their remnants. Although the etiopathogenesis of most odontogenic tumors remains unclear, there have been some advances, recently, in the understanding of the genetic basis of specific odontogenic tumors. The mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/ERK) pathway is intimately involved in the regulation of important cellular functions, and it is commonly deregulated in several human neoplasms. Molecular analysis performed by different techniques, including direct sequencing, next-generation sequencing, and allele-specific qPCR, have uncovered mutations in genes related to the oncogenic MAPK/ERK signaling pathway in odontogenic tumors. Genetic mutations in this pathway genes have been reported in epithelial and mixed odontogenic tumors, in addition to odontogenic carcinomas and sarcomas. Notably, B-Raf proto-oncogene serine/threonine kinase and KRAS proto-oncogene GTPase pathogenic mutations have been reported in a high proportion of ameloblastomas and adenomatoid odontogenic tumors, respectively. In line with the reports about other neoplasms that harbor a malignant counterpart, the frequency of p.V600E mutation is higher in ameloblastoma (64% in conventional, 81% in unicystic, and 63% in peripheral) than in ameloblastic carcinoma (35%). The objective of this study was to review MAPK/ERK genetic mutations in benign and malignant odontogenic tumors. Additionally, such genetic alterations were discussed in the context of tumorigenesis, clinical behavior, classification, and future perspectives regarding therapeutic approaches.
PubMed: 35048058
DOI: 10.3389/froh.2021.740788 -
Journal of Pharmacy & Bioallied Sciences Jul 2014Ameloblastic carcinoma is a rare odontogenic tumor exhibiting not only features of ameloblastoma, but also features of carcinoma. Clinical dissemination of this lesion...
Ameloblastic carcinoma is a rare odontogenic tumor exhibiting not only features of ameloblastoma, but also features of carcinoma. Clinical dissemination of this lesion is more aggressive and rapid than that of ameloblastoma and it can metastasize to the lung or regional lymph node. Histologically, there are features of both ameloblastoma and carcinoma. <50 cases have been reported until 2011. We report a series of six cases with our treatment modalities.
PubMed: 25210376
DOI: 10.4103/0975-7406.137473 -
Journal of Oral and Maxillofacial... Feb 2019Ameloblastic Carcinoma is a rare malignant Odontogenic tumour with characteristic histopathology and clinical features which requires aggressive surgical treatment and...
Ameloblastic Carcinoma is a rare malignant Odontogenic tumour with characteristic histopathology and clinical features which requires aggressive surgical treatment and surveillance and therefore differs from ameloblastoma. It is possible that ameloblastoma shows a variety of histologic and biologic behaviour ranging from benign to frank malignancy. Cases of ameloblastoma should thus be studied carefully, correlating their histologic pattern with biologic behaviour to direct subtle changes in histology that may predict the aggressiveness of the tumor. Thus the identifying features of Ameloblastic Carcinoma must be carefully known and recognized by dental professionals. The purpose of this article is to report a rare case of Ameloblastic Carcinoma and to highlight the clinical, radiological and variable histological features with possible differential diagnosis.
PubMed: 30967729
DOI: 10.4103/jomfp.JOMFP_318_18