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Head and Neck Pathology Mar 2022The 5 edition of the World Health Organization (WHO) Classification of Head and Neck Tumours (2022) comes out only five years after the previous edition, however it...
The 5 edition of the World Health Organization (WHO) Classification of Head and Neck Tumours (2022) comes out only five years after the previous edition, however it presents important updates that run in parallel with the rapid progression involving the increasingly sophisticated molecular investigation and its interpretation, some of which already have therapy-related impact. This manuscript provides an overview of the leading changes introduced in the classification of Odontogenic and Maxillofacial Bone Tumours that encompasses cysts of the jaws, odontogenic tumours, giant cell lesions and bone cysts, and bone and cartilage tumours. This is the first edition that Essential and Desirable Diagnostic Features were added for each entity, so that the most important clinical, microscopic and/or radiologic features were encapsulated and briefly highlighted. Surgical ciliated cyst was added to the group of odontogenic cysts, adenoid ameloblastoma was a newly recognized benign epithelial odontogenic tumour, and segmental odontomaxillary dysplasia was introduced in the group of fibro-osseous tumours and dysplasia. In addition, rhabdomyosarcoma with TFCP2 rearrangement, was introduced into the group of malignant jawbone tumours. The unique genetic aberrations distinguish it from other types of rhabdomyosarcomas. On the other hand, melanotic neuroectodermal tumour of infancy and osteoid osteoma were deleted from the benign bone and cartilageneous tumours, as was the hematolymphoid tumour of solitary plasmacytoma of bone. We systematically reviewed each entity in this chapter and provided important updated findings for selected topics that can further aid in the diagnostic process for challenging cases, broaden insights on the logic of the present classification, and finally, emphasize the potential that some of the molecular results may have in the near future to set new treatment approaches.
Topics: Bone Neoplasms; DNA-Binding Proteins; Head and Neck Neoplasms; Humans; Odontogenic Cysts; Odontogenic Tumors; Transcription Factors; World Health Organization
PubMed: 35312978
DOI: 10.1007/s12105-021-01404-7 -
Sultan Qaboos University Medical Journal Aug 2022This article aimed to collectively present the demographic, clinical, radiographic and histopathological features as well as the treatment performed along with its... (Review)
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.
Topics: Adenoids; Ameloblastoma; Biopsy; Humans; Odontogenic Tumors
PubMed: 36072074
DOI: 10.18295/squmj.9.2021.127 -
Indian Journal of Dental Research :... 2022Ameloblastoma is a benign, locally aggressive neoplasm that needs extensive surgical resection. The goal of this article is to obtain an in-depth review of benign... (Review)
Review
Ameloblastoma is a benign, locally aggressive neoplasm that needs extensive surgical resection. The goal of this article is to obtain an in-depth review of benign ameloblastomas to determine the available level of evidence and the possible benefit of targeted therapeutics for the treatment of ameloblastoma and BRAF V600E mutation in ameloblastoma. An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE, EBSCO, and Web of Science for eligible studies published between 1975 and 2021. The systematic review is registered with INPLASY (INPLASY202260018). The review included 2 case series and 17 case reports. The histopathological type, anatomic location, expression of BRAF mutation, additional mutations, and molecular-targeted therapies of the 19 reviewed articles were summarized and tabulated. Interestingly, the majority of the primary site of ameloblastoma was located in the mandible (80.9%) compared to the maxilla (17%). The tumour size was reported in nine of the included studies. Most of the included studies in the review exhibited ameloblastoma with BRAF V600E mutations and responded to molecular-targeted therapies. Molecular therapies employing BRAF and/or MEK inhibitors in ameloblastoma with BRAF V600E mutations proved to be an appropriate treatment based on the limited available evidence. It is essential further to deepen our understanding at the clinical and molecular level to enhance the precision of management of ameloblastoma.
Topics: Humans; Ameloblastoma; Molecular Targeted Therapy; Mutation; Proto-Oncogene Proteins B-raf
PubMed: 36656197
DOI: 10.4103/ijdr.ijdr_456_22 -
Head and Neck Pathology Dec 2022Craniopharyngiomas and ameloblastomas are tumors of epithelial origin, mostly characterized by a benign course, slow growth and for being locally invasive. Some studies... (Review)
Review
BACKGROUND
Craniopharyngiomas and ameloblastomas are tumors of epithelial origin, mostly characterized by a benign course, slow growth and for being locally invasive. Some studies highlight the similarity of these neoplasms, especially regarding histopathological aspects. In this context, the aim of the present study was to carry out a systematic literature review correlating the clinical, radiographic, and histopathological aspects of these two tumors.
METHODS
Searches were conducted at the Pubmed, Periódicos Capes, Scopus, Science Direct, Web of Science and Scielo databases, according to the following inclusion criteria: publications in English or Spanish, from the 2000s and 2021, comprising case report studies, case series and literature reviews.
RESULTS
Considering clinical and radiographic aspects, it is evident that craniopharyngiomas and ameloblastomas exhibit few similarities. Histopathologically, however, adamantinomatous craniopharyngiomas are the type of tumor that most resembles ameloblastomas, both concerning the formation of palisade epithelial cords and epithelial formations. Regarding to recurrences in cases of craniopharyngioma, it appears that a more radical surgical resection is more related to a lower recurrence rate for both craniopharyngiomas and ameloblastomas. As for the outcome, it was observed that craniopharyngiomas have a greater relationship with possible systemic disorders.
CONCLUSIONS
This histopathological similarity is related to their origin, since both craniopharyngiomas and ameloblastomas share a relationship with the oral cavity, either partially, as in the case of craniopharyngiomas, or totally, as in ameloblastomas, not comprising the same lesion in different locations. It is important to note that the differential morphogenetic evidence observed herein between these lesions opens up a new field of study aiming at better treatment alternatives in the future.
Topics: Humans; Neoplasms
PubMed: 35920974
DOI: 10.1007/s12105-022-01473-2 -
Journal of Clinical and Experimental... May 2019Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO) are uncommon benign mixed odontogenic neoplasms. Although unusual microscopic changes including hybrid... (Review)
Review
BACKGROUND
Ameloblastic fibroma (AF) and ameloblastic fibro-odontoma (AFO) are uncommon benign mixed odontogenic neoplasms. Although unusual microscopic changes including hybrid tumors have been documented in publications, their clinical outcome prediction and treatment modality selection are still challenging due to scarcity. Objective: Analysis of AF/AFO's unusual microscopic variants in order to improve histopathologic diagnosis and to help clinicians in making informed treatment choices.
MATERIAL AND METHODS
An electronic search was performed in PubMed's database using keywords: "ameloblastic fibroma", "ameloblastic fibroodontoma", "ameloblastic fibro-odontoma". The search scheme was limited to articles in English, dated 'January 1998' to 'October 2018', with full texts (case reports and series) and human studies. Eligibility criteria included publications having enough clinical, radiological, and histological data to confirm their diagnosis. Age, sex, lesions' location, radiologic features, signs, symptoms, treatment approaches, and recurrences were recorded and analyzed.
RESULTS
In this systematic review, 11 articles (reporting 14 cases) were selected. Patients' mean age was 13.75 years (male/female = 1.8). The posterior region of the mandible was the lesions' commonest location (57.14%). Swelling was reported in 78.57% of the cases, pain in 28.57% but 21.42% were asymptomatic. Radiolucent unilocular appearance was the commonest radiographic feature, but 28.57% of the cases showed a mixed radiolucent-radiopaque appearance. Other reported radiographic findings were impacted tooth (78.57%), root resorption (28.57%), tooth mobility (35.71%), and cortical perforation (14.28%). No recurrences were reported. Calcifying odontogenic cyst (COC) was the commonest lesion associated with AF/AFO (53.33%). Unicystic ameloblastoma and cystic changes without prominent epithelial lining were other reported hybrid lesions. Reported microscopic variations were pigmentation and ghost cell differentiation.
CONCLUSIONS
COC was the commonest lesion associated with AF/AFO. Although COC commonly occurs in the jaws' anterior region, hybrid cases were more common in the posterior area. No malignant transformations were reported. The treatment modality is mostly chosen based on the lesion's most aggressive part. Ameloblastic fibroma, Ameloblastic fibro-odontoma, Odontogenic tumor, Jaw.
PubMed: 31275522
DOI: 10.4317/jced.55460 -
Journal of Dental Research, Dental... 2021Ki-67 is a marker of cell proliferation, used as an important diagnostic marker in the pathologic differentiation of various lesions. It is also relevant for developing... (Review)
Review
Ki-67 is a marker of cell proliferation, used as an important diagnostic marker in the pathologic differentiation of various lesions. It is also relevant for developing targeted molecular therapies. We carried out a systematic review to assess the Ki-67 labeling index (LI) in odontogenic cysts and tumors. Databases were searched, including PubMed (MEDLINE), Scopus, CINHAL, PsycoInfo, the Cochrane Library, and Proquest. The meta-analysis was carried out based on the data of 608 lesions. When a 5% cut-off point was set, ki-67 LI of all benign odontogenic tumors dropped below this point. All the malignant tumors demonstrated an LI of over 15.3%; a significantly higher Ki-67 LI in malignant odontogenic lesions (17.59±2.80) was observed. Among benign tumors, the largest and the smallest Ki-67 LIs were seen in ameloblastoma (4.39±0.47) and adenomatoid odontogenic tumor (0.91±1.71). The mean values of Ki-67 LI in tumors and cysts were 4.23 (0.38) and 1.04 (0.07), respectively. Among odontogenic cysts, the highest Ki-67 LI was found in odontogenic keratocyst (OKC) (3.58±0.51), and the lowest in the radicular cyst (1.29±0.62%). Ki-67 LIs in all odontogenic cysts were <3%, except for OKC. This controversial lesion seems to have a profile more similar to a tumor, and a treatment plan similar to tumors might be suggested. We found that odontogenic lesions have diverse proliferative activities that help differentiate between various lesions and suggest therapeutic plans.
PubMed: 33927844
DOI: 10.34172/joddd.2021.012 -
Plastic and Reconstructive Surgery.... Jan 2023Microsurgical advances have led to minimally invasive approaches for mandibular reconstruction. Currently, no resource compares all minimally invasive microvascular...
UNLABELLED
Microsurgical advances have led to minimally invasive approaches for mandibular reconstruction. Currently, no resource compares all minimally invasive microvascular mandibular reconstruction (MIMMR) treatment options.
METHODS
All known cases of MIMMR were identified following the Preferred Reporting Items for Systematic Reviews, Meta-Analyses guidelines, and our own surgical experience. Patient demographics, MIMMR type [submandibular (SM), modified facelift/retroauricular (MFL/RA), or intraoral (IO)], methodology, and clinical outcomes were analyzed with the Fisher exact and Kruskal-Wallis tests.
RESULTS
Forty-seven patients underwent MIMMR. Ameloblastoma was the most common pathology treated using all approaches, and MFL/RA was the only approach used to treat squamous cell carcinoma ( = 0.0103). Reconstruction was reported for large, bilateral defects only via the SM or IO approach ( = 0.0216). The iliac crest or fibula was used as a donor site. The facial artery was the most common recipient vessel using the IO and SM approaches, whereas the superior thyroid and external carotid vessels were the most common in the MFL/RA approach ( < 0.0001). Virtual planning was used in all cases performed via an IO approach, 80.0% of cases using an SM approach, and no MFL/RA cases ( < 0.0001). Good aesthetic and functional outcomes were reported for every patient, and there was no difference in complication rates ( = 0.2880).
CONCLUSIONS
Minimally invasive approaches are safe and effective treatment options for patients requiring mandibular microsurgery, usually in the setting of benign pathology. The IO and SM approaches usually rely on the facial vessels, whereas the MFL/RA approach permits access to the superior thyroid and external carotid vessels and cervical lymphadenectomy.
PubMed: 36699208
DOI: 10.1097/GOX.0000000000004733 -
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 -
BMC Oral Health Dec 2023Ameloblastoma (AM), the benign counterpart of ameloblastic carcinoma, is a benign odontogenic tumor of epithelial origin, naturally aggressive, with unlimited growth...
BACKGROUND
Ameloblastoma (AM), the benign counterpart of ameloblastic carcinoma, is a benign odontogenic tumor of epithelial origin, naturally aggressive, with unlimited growth potential and a high tendency to relapse if not adequately removed. Patients with AM treated surgically can benefit from dental implant therapy, promoting oral rehabilitation and improving their quality of life. The present study aimed to determine the survival rate of dental implants placed after surgical treatment of patients affected by AM. In addition, there were two secondary objectives: 1) To evaluate which dental implant loading protocols are most frequently used and 2) To determine the type of prosthetic restoration most commonly used in these patients.
METHODS
The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines were followed during the study. Searches were performed in three databases (PubMed/MEDLINE, Scopus, and Google Scholar) until November 2023. Additionally, the electronic search was enriched by an iterative hand search of journals related to oral pathology and medicine, maxillofacial surgery, and oral prosthodontics and implantology. Only reports and case series in English from January 2003 to date were included. The Joanna Briggs Institute tool (JBI-Case Reports/Case Series) was used for the study quality assessment.
RESULTS
The total number of patients and implants studied were 64 and 271, respectively, all with surgically treated AM. The patient's ages ranged from 8 to 79 years, with a mean (SD) age of 37.3 ± 16.4. Fifty-three percent were male and 47% were female. The range of follow-up duration was 1 to 22 years. An implant survival/success rate of 98.1% was reported. In addition, most of them were conventionally loaded (38.3%). Hybrid implant-supported fixed dentures were the most commonly used by prosthodontists (53%).
CONCLUSIONS
Oral rehabilitation with dental implants inserted in free flaps for orofacial reconstruction in surgically treated patients with AM can be considered a safe and successful treatment modality.
Topics: Adolescent; Adult; Aged; Child; Female; Humans; Male; Middle Aged; Young Adult; Ameloblastoma; Dental Implantation, Endosseous; Dental Implants; Dental Prosthesis, Implant-Supported; Dental Restoration Failure; Neoplasm Recurrence, Local; Odontogenic Tumors; Quality of Life; Treatment Outcome
PubMed: 38110933
DOI: 10.1186/s12903-023-03765-7 -
Metastasizing Ameloblastoma: A 10 Year Clinicopathological Review with an Insight Into Pathogenesis.Head and Neck Pathology Sep 2021Ameloblastoma, a benign but locally aggressive odontogenic tumor, often demonstrates metastasis despite benign histological features and this variant is termed as...
Ameloblastoma, a benign but locally aggressive odontogenic tumor, often demonstrates metastasis despite benign histological features and this variant is termed as metastasizing ameloblastoma (METAM). It was classified under the malignant category in the 2005 WHO but has been re-classified under benign epithelial odontogenic tumors in the latest 2017 WHO classification. The present review aimed at gathering the available data on METAM to update the current cognizance about the pathology. Comprehensive search of the databases (viz., PubMed, Medline, SCOPUS, Web of Science, EMBASE and Google Scholar) was done for published articles on METAM following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 42 cases were extracted. The mean age of occurrence was 42.71 ± 15.87 years. A slight male predilection was noted. Mandibular cases showed more metastasis than maxillary cases. Follicular ameloblastoma was most frequently encountered at secondary site followed by plexiform type. Lungs were the most commonly affected secondary sites. METAM is a rare odontogenic tumor and the diagnosis is usually made in retrospect. Inadequate treatment may result in multiple recurrences and metastasis in rare instances. Metastasis in ameloblastoma appears to be multi-factorial in nature and needs further investigation in untapped territory like exploration of quantum effects at cellular and molecular levels.
Topics: Adult; Aged; Ameloblastoma; Female; Humans; Jaw Neoplasms; Male; Middle Aged
PubMed: 33394372
DOI: 10.1007/s12105-020-01258-5