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Cancer Management and Research 2021Ameloblastoma is a benign odontogenic neoplasm with a high local recurrence rate if the operation is not thorough. However, a useful clinical tool for the quantitative...
PURPOSE
Ameloblastoma is a benign odontogenic neoplasm with a high local recurrence rate if the operation is not thorough. However, a useful clinical tool for the quantitative assessment of the prognosis and risk of postoperative recurrence of ameloblastoma has not yet been constructed. This study aims to develop a prognostic nomogram model for ameloblastoma of the jaw to assist surgeons in surgical decision-making.
PATIENTS AND METHODS
Patients who underwent initial surgery for ameloblastoma in our department from October 2004 to March 2020 were enrolled and randomly divided into training and validation sets. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify the independent prognostic factors, from which a nomogram for predicting 3-, 5- and 10-year recurrence-free survival (RFS) of ameloblastoma was constructed using the training set and internally validated using the validation set. The model performance was assessed by Harrell's concordance index (C-index) and calibration curves.
RESULTS
A total of 302 eligible patients with ameloblastoma were enrolled, 54 of whom were confirmed to relapse during the follow-up period of 6 to 191 months. Four independent predictors, including cortical bone perforation, root(s) resorption, WHO classification, and treatment pattern, were identified and included in the construction of a nomogram for recurrence-free survival (RFS), which showed promising calibration performance and discrimination in the training set (C-index 0.790, 95% confidence interval [CI] 0.735-0.845) and the validation set (C-index 0.734, 95% CI 0.599-0.869).
CONCLUSION
A favorable nomogram was developed that accurately predicted the RFS of patients with ameloblastoma based on individual characteristics. Risk stratification using the nomogram could optimize tailored therapy and follow-up.
PubMed: 34103995
DOI: 10.2147/CMAR.S307517 -
Journal of Istanbul University Faculty... 2017Odontogenic tumors are a heterogeneous group of lesions of diverse clinical behavior and histopathologic types, ranging from hamartomatous lesions to malignancy. Because... (Review)
Review
Odontogenic tumors are a heterogeneous group of lesions of diverse clinical behavior and histopathologic types, ranging from hamartomatous lesions to malignancy. Because odontogenic tumors arise from the tissues which make our teeth, they are unique to the jaws, and by extension almost unique to dentistry. Odontogenic tumors, as in normal odontogenesis, are capable of inductive interactions between odontogenic ectomesenchyme and epithelium, and the classification of odontogenic tumors is essentially based on this interaction. The last update of these tumors was published in early 2017. According to this classification, benign odontogenic tumors are classified as follows: Epithelial, mesenchymal (ectomesenchymal), or mixed depending on which component of the tooth germ gives rise to the neoplasm. Malignant odontogenic tumors are quite rare and named similarly according to whether the epithelial or mesenchymal or both components is malignant. The goal of this review is to discuss the updated changes to odontogenic tumors and to review the more common types with clinical and radiological illustrations.
PubMed: 29354306
DOI: 10.17096/jiufd.52886 -
International Journal of Molecular and... 2016Odontogenic tumors constitute a group of heterogeneous lesions of benign and malignant neoplasms with variable aggressiveness. Ameloblastomas are a group of benign but...
Odontogenic tumors constitute a group of heterogeneous lesions of benign and malignant neoplasms with variable aggressiveness. Ameloblastomas are a group of benign but locally invasive neoplasms that occur in the jaws and are derived from epithelial elements of the tooth-forming apparatus. We previously described orosomucoid-1 protein expression in odontogenic myxomas. However, whether orosomucoid-1 is expressed in other odontogenic tumors remains unknown. Since orosomucoid-1 belongs to a group of acute-phase proteins and has many functions in health and disease, we identified and analyzed orosomucoid-1 expression in ameloblastoma variants and ameloblastic carcinoma using western blot and immunohistochemical techniques. Thirty cases of ameloblastoma were analyzed for orsomucoid-1; five specimens were fresh for western blot study (four benign ameloblastomas and one ameloblastic carcinoma), and 25 cases of benign ameloblastoma for immunohistochemical assays. Orosomucoid-1 was widely expressed in each tumor variant analyzed in this study, and differential orosomucoid-1 expression was observed between benign and malignant tumor. Orosomucoid-1 may play an important role in the behavior of ameloblastomas and influence the biology and development of the variants of this tumor.
PubMed: 27386438
DOI: No ID Found -
Journal of Cancer Research and... 2019Metastasizing ameloblastoma (MA) is a very rare odontogenic tumor with 2% of incidence rate. It exhibits benign histopathological features and malignant intrinsic... (Review)
Review
Metastasizing ameloblastoma (MA) is a very rare odontogenic tumor with 2% of incidence rate. It exhibits benign histopathological features and malignant intrinsic quality in the form of metastasis which makes it a little more than a pathological curiosity. Various molecular aspects related with malignant behavior have been discussed. Because of this, it provides a diagnostic challenge for clinicians and surgeons. It is an elusive lesion which should be more researched and studied so that definitive diagnostic features can be put forward. The objective of this paper is to review the molecular aspect involved in the pathogenesis of MA which will aid in differentiating non-MA from MA and thus helping in providing proper treatment at an early stage.
Topics: Ameloblastoma; Biomarkers, Tumor; Disease Management; Disease Susceptibility; Epithelial-Mesenchymal Transition; Humans; Neoplasm Metastasis; Neoplasm Staging; Tumor Microenvironment
PubMed: 31169204
DOI: 10.4103/jcrt.JCRT_268_17 -
Journal of Clinical and Experimental... Jun 2020Ameloblastoma is a rare tumor which develops from odontogenic epithelium and its remnants and it occurs in the jaws. Peripheral ameloblastomas are rare and benign...
BACKGROUND
Ameloblastoma is a rare tumor which develops from odontogenic epithelium and its remnants and it occurs in the jaws. Peripheral ameloblastomas are rare and benign extraooseous ameloblastomas which effects soft tissues. This case report declares a peripheral ameloblastoma which is a rare type of ameloblastoma.
MATERIAL AND METHODS
34 year old female patient referred with a complaint of a gingival growth at right lower premolar area. A firm and granular surfaced gingival growth with the color of pink and red and having 1.5x1 cm sizes was observed at the mentioned area. With an incision from lower right second incisor tooth to lower right second molar tooth a flap from bone was made and lesion was excised. After then specimen was submitted to histopathologic examination. After clinical, radiological and pathological examinations lesion was described as peripheral ameloblastoma.
RESULTS
At the control examination after three months of excision there was no recurrence and patieant has no complaint.
CONCLUSIONS
Although reccurens rate of peripheral ameloblastomas are low, long-term follow-ups are suggested Patient was informed about the importance of regular controls for early diagnosis of possible reccurenses and regular controls were made during one year after excision. Peripheral ameloblastoma, gingiva, gingival hyperplasia, gingival lesion, alveolar mucosa, extraosseous.
PubMed: 32665822
DOI: 10.4317/jced.56757 -
Indian Journal of Otolaryngology and... Oct 2022Ameloblastoma is a locally aggressive benign neoplasm of jaw that has high propensity to recur. Pathological subtype and intent of surgical excision during primary...
Ameloblastoma is a locally aggressive benign neoplasm of jaw that has high propensity to recur. Pathological subtype and intent of surgical excision during primary surgery are two factors that are known to affect the prognosis in these cases. Nevertheless, there are hardly any studies which have studied recurrent ameloblastoma cases. Apart from sharing a tertiary care cancer center's experience in managing a series of recurrent ameloblastoma cases, we discuss some of the recent literature related to pathophysiology and principles related to their surgical management. Retrospective chart review of all those recurrent ameloblastoma cases which were operated between October 2013 and January 2016 and were subsequently followed up for minimum of 3 years. Total of 9 recurrent ameloblastoma cases were operated in the study period. All our patients had less-radical or non-curative intent surgical treatment in the past, and current treatment consisted wide excision of the involved segment of mandible with free fibular reconstruction. Among the 6 patients who were followed up for more than 3 years, none developed recurrence at 56.5 months of mean follow up duration. Almost all these patients had optimal results with good quality of life in terms of oral speech intellectuality and cosmetic perception of self. Complete excision of the involved segment of bone with reconstruction using the composite free fibular graft can provide optimal functional outcomes and can significantly lessen the chances of further recurrences.
PubMed: 36452534
DOI: 10.1007/s12070-020-01790-4 -
Clinics and Practice Jan 2012Ameloblastoma is a benign odontogenic tumor. These are usually asymptomatic until a large size is attained. Ameloblastoma has tendency to spread locally and has a high...
Ameloblastoma is a benign odontogenic tumor. These are usually asymptomatic until a large size is attained. Ameloblastoma has tendency to spread locally and has a high recurrence rate. Majority of ameloblastomas (80%) arise from the mandible. Ameloblastoma arising from anterior mandibular region (symphysis-menti) is rare. Very few cases of midline anterior ameloblastomas are reported in the literature. They often require wide local excision. Reconstruction of mandible in these cases is challenging. We present a case of mandibular ameloblastoma arising from symphysis-menti. Patient underwent wide surgical excision of the tumor followed by immediate reconstruction using free fibular vascular flap, stabilized with titanium reconstructive plates. A brief case report ands review of literature is presented.
PubMed: 24765429
DOI: 10.4081/cp.2012.e30 -
Brazilian Dental Journal 2021The Inhibitor of Growth (ING) gene family is a group of tumor suppressor genes that play important roles in cell cycle control, senescence, DNA repair, cell...
UNLABELLED
The Inhibitor of Growth (ING) gene family is a group of tumor suppressor genes that play important roles in cell cycle control, senescence, DNA repair, cell proliferation, and apoptosis. However, inactivation and downregulation of these proteins have been related in some neoplasms. The present study aimed to evaluate the immunohistochemical profiles of ING3 and ING4 proteins in a series of benign epithelial odontogenic lesions.
METHODS
The sample comprised of 20 odontogenic keratocysts (OKC), 20 ameloblastomas (AM), and 15 adenomatoid odontogenic tumors (AOT) specimens. Nuclear and cytoplasmic immunolabeling of ING3 and ING4 were semi-quantitatively evaluated in epithelial cells of the odontogenic lesions, according to the percentage of immunolabelled cells in each case. Descriptive and statistics analysis were computed, and the p-value was set at 0.05.
RESULTS
No statistically significant differences were found in cytoplasmic and nuclear ING3 immunolabeling among the studied lesions. In contrast, AOTs presented higher cytoplasmic and nuclear ING4 labeling compared to AMs (cytoplasmic p-value = 0.01; nuclear p-value < 0.001) and OKCs (nuclear p-value = 0.007).
CONCLUSION
ING3 and ING4 protein downregulation may play an important role in the initiation and progression of more aggressive odontogenic lesions, such as AMs and OKCs.
Topics: Ameloblastoma; Cell Cycle Proteins; Cell Proliferation; Homeodomain Proteins; Humans; Odontogenic Cysts; Odontogenic Tumors; Tumor Suppressor Proteins
PubMed: 34787253
DOI: 10.1590/0103-6440202104279 -
Laboratory Investigation; a Journal of... Jan 2022Ameloblastoma (AB) is the most common benign epithelial odontogenic tumor occurring in the jawbone. AB is a slowly growing tumor but sometimes shows a locally invasive...
Ameloblastoma (AB) is the most common benign epithelial odontogenic tumor occurring in the jawbone. AB is a slowly growing tumor but sometimes shows a locally invasive and an aggressive growth pattern with a marked bone resorption. In addition, the local recurrence and distant metastasis of AB also sometimes occurs, which resembles one of the typical malignant potentials. From these points of view, to understand better the mechanisms of AB cell migration or invasion is necessary for the better clinical therapy and improvements of the patients' quality of life. Microtubules in eukaryotic cells reveal the shape of hollow cylinders made up of polymerized alpha (α)- and beta (β)-tubulin dimers and form the cytoskeleton together with microfilaments and intermediate filaments. Microtubules play important roles in cell migration by undergoing assembly and disassembly with post-translational modifications. Stability of microtubules caused by their acetylation is involved in cell migration. In this study, we investigated the expression and distribution of acetylated α-tubulin and alpha-tubulin N-acetyltransferase 1 (αTAT1), an enzyme which acetylates Lys-40 in α-tubulin, in AB specimens, and analyzed how tubulin was acetylated by αTAT1 activation in a human AB cell line, AM-1. Finally, we clarified that TGF-β-activated kinase1 (TAK1) was phosphorylated by TGF-β stimulation, then, induced tubulin acetylation via αTAT1 activation, which subsequently activated the migration and invasion of AB cells.
Topics: Acetylation; Acetyltransferases; Adolescent; Adult; Aged; Ameloblastoma; Cell Line, Tumor; Cell Movement; Female; Humans; Immunohistochemistry; Jaw Neoplasms; MAP Kinase Kinase Kinases; Male; Microtubule Proteins; Middle Aged; Neoplasm Invasiveness; RNA Interference; Transforming Growth Factor beta; Tubulin; Young Adult
PubMed: 34508164
DOI: 10.1038/s41374-021-00671-w -
Frontiers in Veterinary Science 2022Ameloblastoma is a benign epithelial odontogenic tumor with the capacity to aggressively invade the surrounding bone. Surgical removal of the tumor can result in... (Review)
Review
Ameloblastoma is a benign epithelial odontogenic tumor with the capacity to aggressively invade the surrounding bone. Surgical removal of the tumor can result in extended disease-free interval (cure). However, controversy surrounds the most appropriate surgical margin required to prevent local recurrence while simultaneously minimizing morbidity. excisional surgery carries the risk of major complications such as mandibular drift, hemorrhage, and oronasal fistula formation. Conservative therapy without a safety margin reduces potential morbidity but is likely to result in local recurrence. No reliable rate, nor time to recurrence, is documented but may be as high as 91% with conservative therapy. Conversely, surgery with a 10- to 20-mm margin is associated with a 0-4.6% recurrence rate. There is no documented difference in the recurrence rate with a 10- vs. 20-mm margin. The correlation of the histologic margin with the recurrence rate following excisional surgery has not determined a required histologic safety margin. Rather, no local recurrence occurs despite narrow or incomplete margins. Thus, pathologic margins > 0 mm may be sufficient to prevent local recurrence or recurrence may be protracted. Accordingly, a narrow (5-10 mm) gross surgical margin may be the most appropriate. Additional research is required for confirmation, and only level 4 evidence on safety margins has been achieved thus far. Future work should focus on defining the extension of neoplastic cells past the demarcation of ameloblastoma on variable diagnostic imaging modalities as well as determining the recurrence rate with various surgical and histologic safety margins.
PubMed: 35392113
DOI: 10.3389/fvets.2022.830258