-
Acta Bio-medica : Atenei Parmensis May 2023The purpose of this study was to determine the clinical and histological features and treatment of peripheral ameloblastoma. Peripheral Ameloblastoma is a rare benign...
BACKGROUND AND AIM
The purpose of this study was to determine the clinical and histological features and treatment of peripheral ameloblastoma. Peripheral Ameloblastoma is a rare benign odontogenic tumor that concerns soft tissue and have a typical extraosseous localization.
METHODS
Aim of this work is to show its clinical and histological characters, in order to define some useful information for differential diagnosis with other oral neoformations, comparing literature with our data, collected in ten years of clinical activity of Oral and Maxillofacial Surgery Unit of Policlinico Tor Vergata in Rome.
RESULTS
Prognosis of PA is certainly favourable, with a restitutio ad integrum close to 100%. In the period between October 2011 and November 2021, we reported 8 diagnoses of P.A. Medium age of the group with diagnosis of PA was 71,4 y with a SD: 3,65. P.A.'s incidence in our sample of patients was 0,26%.
CONCLUSIONS
PA is a benign odontogenic tumor that requires a careful diagnosis, a complete surgical eradication and adequate follow up, because malignant evolution is rare but possible.
Topics: Humans; Ameloblastoma; Odontogenic Tumors; Prognosis; Diagnosis, Differential; Incidence
PubMed: 37213074
DOI: 10.23750/abm.v94iS1.13527 -
JNMA; Journal of the Nepal Medical... Mar 2023Adenomatoid odontogenic tumour is a rare benign, odontogenic tumour with uncertain histogenesis. Whether it is a hamartoma or a neoplasm is still a controversial topic....
UNLABELLED
Adenomatoid odontogenic tumour is a rare benign, odontogenic tumour with uncertain histogenesis. Whether it is a hamartoma or a neoplasm is still a controversial topic. It is usually associated with an unerupted maxillary canine. Here, we discuss a follicular adenomatoid odontogenic tumour in a young girl with uncommon features such as it arose from two unerupted teeth and partial resorption of the roots of other normal teeth. The tumour was large enough to completely occupy the maxillary sinus. It was treated with enucleation and curettage by lateral rhinotomy approach.
KEYWORDS
adenomatoid tumor; case reports; hamartoma; odontogenic cysts.
Topics: Humans; Maxillary Sinus; Ameloblastoma; Odontogenic Tumors; Hamartoma
PubMed: 37203949
DOI: 10.31729/jnma.8071 -
Head and Neck Pathology Sep 2023Keratoameloblastoma is a poorly characterized and rarely reported odontogenic neoplasm that can exhibit overlapping histopathologic features with conventional...
BACKGROUND
Keratoameloblastoma is a poorly characterized and rarely reported odontogenic neoplasm that can exhibit overlapping histopathologic features with conventional ameloblastoma and keratocystic odontogenic tumor (KCOT), with an ambiguous relationship to the so-called solid KCOT.
METHODS
A peripheral maxillary tumor causing bone saucerization in a 54-year-old male is described and investigated with immunohistochemistry and Next-Generation Sequencing (NGS).
RESULTS
Microscopically, the tumor comprised of a predominantly plexiform proliferation of odontogenic epithelium with central keratinization and evidence of surface origin. Peripheral cells exhibited nuclear palisading with variable reverse polarization, while stellate reticulum-like areas were observed internally. A few follicles and a few foci in the lining of cystic spaces revealed increased cellularity with cells exhibiting small but conspicuous nucleoli, focal nuclear hyperchromatism, and a few mitoses mostly seen in the peripheral outer cell layer. Nuclear staining for ki-67 was increased in those areas when compared with the other cystic, follicular, and plexiform areas. These features were interpreted as cytologic atypia suggesting also the possibility of a malignant process. Immunohistochemically, the tumor was positive for CK19 and negative for BRAF VE1, calretinin, and CD56. Ber-Ep4 was only focally positive. By sequencing, an ARID1A c.6527_6538delAG frameshift mutation (VAF: 5.8%), classified as likely oncogenic, and an FBXW7 c.1627 A > G missense mutation (VAF: 8.0%), classified as a variant of uncertain significance, were detected. Two mutations, probably germline (VAF ~ 50%), were recorded for RNF43 and FBXW7. No pathogenic variants were identified in PTCH1, BRAF, NRAS, HRAS, KRAS, FGFR2, or SMO genes.
CONCLUSION
The significance of an ARID1A variant in keratoameloblastoma is uncertain since this variant has not been reported in ameloblastoma or KCOT, to date. Alternatively, it may characterize malignant transformation in the present case since ARID1A mutations have been encountered in various cancers. Sequencing of additional cases is necessary to determine whether this may represent a recurrent genomic event.
Topics: Male; Humans; Middle Aged; Ameloblastoma; F-Box-WD Repeat-Containing Protein 7; Proto-Oncogene Proteins B-raf; Odontogenic Tumors; Odontogenic Cysts; Mutation; DNA-Binding Proteins; Transcription Factors
PubMed: 37195520
DOI: 10.1007/s12105-023-01549-7 -
Ear, Nose, & Throat Journal May 2023Ameloblastic carcinoma (AC) is a rare and aggressive malignant epithelial odontogenic tumor making up less than 1% of malignant head and neck tumors. The majority of...
Ameloblastic carcinoma (AC) is a rare and aggressive malignant epithelial odontogenic tumor making up less than 1% of malignant head and neck tumors. The majority of cases occur in the mandible with a minority occurring in the maxilla. Most occur de novo, while rare cases of AC have resulted from transformation from ameloblastoma. Here, we present a case in which a 30-year-old man presented with proptosis and a recurrent right temporal mass, which had been previously diagnosed as ameloblastoma on surgical pathology. CT findings demonstrated local invasion, and he was subsequently taken to the operating room for right craniotomy, infratemporal and middle cranial fossa tumor resection, and right modified radical neck dissection with reconstruction. Final pathology, which included areas of early focal necrosis, loss of peripheral palisading, and hyperchromatism, confirmed the diagnosis of ameloblastoma with transformation to AC. We further discuss radiologic and histopathological signs of this rare tumor, as well as recommended treatment modalities.
PubMed: 37158333
DOI: 10.1177/01455613231172857 -
Zhongguo Yi Xue Ke Xue Yuan Xue Bao.... Apr 2023Objective To evaluate the accuracy of different convolutional neural networks (CNN),representative deep learning models,in the differential diagnosis of ameloblastoma...
Objective To evaluate the accuracy of different convolutional neural networks (CNN),representative deep learning models,in the differential diagnosis of ameloblastoma and odontogenic keratocyst,and subsequently compare the diagnosis results between models and oral radiologists. Methods A total of 1000 digital panoramic radiographs were retrospectively collected from the patients with ameloblastoma (500 radiographs) or odontogenic keratocyst (500 radiographs) in the Department of Oral and Maxillofacial Radiology,Peking University School of Stomatology.Eight CNN including ResNet (18,50,101),VGG (16,19),and EfficientNet (b1,b3,b5) were selected to distinguish ameloblastoma from odontogenic keratocyst.Transfer learning was employed to train 800 panoramic radiographs in the training set through 5-fold cross validation,and 200 panoramic radiographs in the test set were used for differential diagnosis.Chi square test was performed for comparing the performance among different CNN.Furthermore,7 oral radiologists (including 2 seniors and 5 juniors) made a diagnosis on the 200 panoramic radiographs in the test set,and the diagnosis results were compared between CNN and oral radiologists. Results The eight neural network models showed the diagnostic accuracy ranging from 82.50% to 87.50%,of which EfficientNet b1 had the highest accuracy of 87.50%.There was no significant difference in the diagnostic accuracy among the CNN models (=0.998,=0.905).The average diagnostic accuracy of oral radiologists was (70.30±5.48)%,and there was no statistical difference in the accuracy between senior and junior oral radiologists (=0.883).The diagnostic accuracy of CNN models was higher than that of oral radiologists (<0.001). Conclusion Deep learning CNN can realize accurate differential diagnosis between ameloblastoma and odontogenic keratocyst with panoramic radiographs,with higher diagnostic accuracy than oral radiologists.
Topics: Humans; Ameloblastoma; Deep Learning; Diagnosis, Differential; Radiography, Panoramic; Retrospective Studies; Odontogenic Cysts; Odontogenic Tumors
PubMed: 37157075
DOI: 10.3881/j.issn.1000-503X.15139 -
Journal of Cancer Research and... Apr 2023Ameloblastic carcinoma (AC) is a rare odontogenic malignant epithelial neoplasm of maxillofacial skeleton with a distinct predisposition of the mandible. It can occur in...
Ameloblastic carcinoma (AC) is a rare odontogenic malignant epithelial neoplasm of maxillofacial skeleton with a distinct predisposition of the mandible. It can occur in a wide range of age groups, with a sex predilection in males. It can arise either as a de novo lesion or from preexisting ameloblastoma. AC has a high propensity for local recurrence as well as distant metastasis (chiefly lungs), thus requiring an aggressive surgical approach and a strict surveillance. Owing to the rarity of publications describing AC, little is known about this entity in pediatric patients. We report a case of transformation of ameloblastoma into AC in a 10-year-old child.
Topics: Male; Humans; Child; Ameloblastoma; Mandibular Neoplasms; Odontogenic Tumors; Mandible; Carcinoma
PubMed: 37147971
DOI: 10.4103/jcrt.jcrt_282_22 -
Medical Oncology (Northwood, London,... Apr 2023Ameloblastoma in 66% of the cases harbor a somatic mutation of the "mitogen-activated protein kinase" signaling pathway (BRAF V600E). In V600E mutations, BRAF is in the... (Review)
Review
BACKGROUND
Ameloblastoma in 66% of the cases harbor a somatic mutation of the "mitogen-activated protein kinase" signaling pathway (BRAF V600E). In V600E mutations, BRAF is in the permanent "on" state and relays the growth-promoting signals independently of the EGFR pathway. Therefore, mutant BRAF represents a target for handful of new drugs.
METHODS
We conducted a literature search, with the search terms "Vemurafenib, Dabrafenib, Ameloblastoma, and BRAF." These included seven case reports with nine patients who underwent monotherapy with Dabrafenib or Vemurafenib or combination therapy with Dabrafenib and Trametinib.
RESULTS
The patients age ranges from 10 years up to 86 years. The distribution of women and men is 4:5. Patients with an initial diagnosis of ameloblastoma, as well as recurrences or metastasized ameloblastoma were treated. Indications cover neoadjuvant therapy up to the use in metastasized patients in an irresectable state. Results ranging from "only" tumor size reduction to restitutio ad integrum.
CONCLUSION
We see the use of BRAF Inhibitors to reduce tumor size with consecutive surgical treatment as a reasonable option for therapy. However, we are aware that at present the data are based only on case reports with the longest follow-up of just 38 months. We encourage further clinical trials in the use of BRAF Inhibitors for selecting ameloblastoma patients in a multi-center setting.
Topics: Male; Humans; Female; Child; Vemurafenib; Proto-Oncogene Proteins B-raf; Ameloblastoma; Imidazoles; Protein Kinase Inhibitors; Mutation; Antineoplastic Combined Chemotherapy Protocols
PubMed: 37115331
DOI: 10.1007/s12032-023-01993-z -
Maxillofacial Plastic and... Apr 2023Ameloblastic carcinoma is a malignant form of ameloblastoma and a very rare odontogenic tumor. We report a case of ameloblastic carcinoma that occurred after removal of...
BACKGROUND
Ameloblastic carcinoma is a malignant form of ameloblastoma and a very rare odontogenic tumor. We report a case of ameloblastic carcinoma that occurred after removal of a right-sided mandibular dental implant.
CASE PRESENTATION
A 72-year-old female patient visited her family dentist with a complaint of pain around a lower right implant placed 37 years previously. Although the dental implant was removed with the diagnosis of peri-implantitis, the patient experienced dullness of sensation in the lower lip and was followed up by her dentist, but after no improvement. She was referred to a highly specialized institution where she was diagnosed with osteomyelitis and treated the patient with medication; however, there was no improvement. In addition, granulation was observed in the same area leading to a suspicion of malignancy, and the patient was referred to our oral cancer center. The diagnosis of squamous cell carcinoma was made after a biopsy at our hospital. Under general anesthesia, the patient underwent mandibulectomy, right-sided neck dissection, free flap reconstruction with an anterolateral thigh flap, immediate reconstruction with a metal plate, and tracheostomy. Histological analysis of the resected specimen on hematoxylin and eosin staining showed structures reminiscent of enamel pulp and squamous epithelium in the center of the tumor. The tumor cells were highly atypical, with nuclear staining, hypertrophy, irregular nuclear size, and irregular nuclear shape, all of which were suggestive of cancer. Immunohistochemical analysis showed that Ki-67 was expressed in more than 80% of the targeted area, and the final diagnosis was primary ameloblastic carcinoma.
CONCLUSION
After reconstructive flap transplantation, occlusion was re-established using a maxillofacial prosthesis. The patient remained disease-free at the 1-year 3-month follow-up.
PubMed: 37101080
DOI: 10.1186/s40902-023-00380-y -
Head and Neck Pathology Sep 2023Adenoid ameloblastoma (AdAM) is a frequently recurrent tumor that shows hybrid histological features of both ameloblastoma and adenomatoid odontogenic tumor (AOT). AdAM...
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.
Topics: Female; Humans; Young Adult; Adult; Ameloblastoma; Proto-Oncogene Proteins B-raf; Adenoids; Mutation; Odontogenic Tumors
PubMed: 37093491
DOI: 10.1007/s12105-023-01555-9 -
Journal of Oral and Maxillofacial... 2022Jaw bones can be afflicted by to a diverse group of lesions ranging from developmental, reactive/inflammatory, cystic lesions to tumors and tumor-like lesions.
CONTEXT
Jaw bones can be afflicted by to a diverse group of lesions ranging from developmental, reactive/inflammatory, cystic lesions to tumors and tumor-like lesions.
OBJECTIVES
The objective of this study is to determine the relative frequency, demographic and pathologic profiles of patients with intraosseous jaw lesions from Thailand.
SUBJECTS AND METHODS
Biopsy records from 1995 to 2019 were reviewed. Age, gender and location of the lesions were collected from the biopsy records. Data were analyzed by appropriate statistics using the IBM SPSS software version 22.0.
RESULTS
From 23,344 accessioned cases, 7382 cases (31.62%) were encountered within the jaw bones. Age of the participants ranged from 1 to 96 years with the mean ± standard deviation = 36.05 ± 17.80 years. Pediatric participants (aged ≤16 years) comprised 13.80% of all the participants, whereas the geriatric ones (aged ≥65 years) accounted for 7.55%. The male-to-female ratio was 0.89:1. The majority of lesions were observed in the mandible. The most prevalent intra-osseous jaw lesion was radicular cyst followed by dentigerous cyst and ameloblastoma. The most common malignant tumor was osteosarcoma followed by ameloblastic carcinoma and lymphoma. Among the pediatric participants, dentigerous cyst was the most prevalent jaw lesion, while that in the geriatric participants was radicular cyst.
CONCLUSIONS
This is the largest study on intra-osseous jaw lesions encompassing several pathological entities ever conducted from Thailand. It thus provides an invaluable database for clinicians to formulate a differential diagnosis as well as for the pathologists to render the final diagnosis. The results of this study are in accordance with previous studies in general.
PubMed: 37082059
DOI: 10.4103/jomfp.jomfp_284_21