Central Pleomorphic Adenoma of Mandible Mimicking Ameloblastoma - A Rare Case Report.

Salivary gland neoplasms account for 3% of all head and neck tumours. Pleomorphic adenoma (PA) is the most common salivary gland tumour that mainly occurs in the parotid gland, followed by minor salivary glands of the oral cavity, however, the occurrence of PA inside the jaw bones is exceedingly rare and very few cases have been reported in the literature. Inside jaw bones these lesions tend to imitate large osteolytic lesions encompass a diagnostic challenge. An exhaustive review of the literature revealed only 10 cases of central pleomorphic adenoma. We present a rare case of primary PA that occurred inside the mandible and was provisionally diagnosed as ameloblastoma.

Prominent osteolysis in the maxilla: case report of an odontogenic fibroma mimicking a cyst.

BACKGROUND: Odontogenic fibroma (OF) is a rare benign odontogenic tumor of ectomesenchymal origin, mostly affecting the tooth-bearing portions of the jaws in middle-aged patients. Whilst small lesions tend to be clinically asymptomatic, varying unspecific clinical symptoms occur with an increase in size and may mimic odontogenic or other maxillofacial bone tumors, cysts, or fibro-osseous lesions of the jaws. CASE PRESENTATION: A 31-year-old female patient presented with a hard, non-fluctuating protrusion in the vestibule of the upper right maxilla. It was visualized on cone beam computed tomography (CBCT) as space-occupying osteolysis with the displacement of the floor and facial wall of the maxillary sinus, mimicking a cyst-like lesion. The tissue was surgically removed and identified as an OF in the histopathological examination. One year after the surgery, restitution of regular sinus anatomy and physiological intraoral findings were observed. CONCLUSIONS: This case report emphasizes that rare entities, like the maxillary OF presented, often demonstrate nonspecific clinical and radiological findings. Nevertheless, clinicians need to consider rare entities as possible differential diagnoses and plan the treatment accordingly. Histopathological examination is essential to conclude the diagnosis. OF rarely recur after proper enucleation.

Clinical and Radiologic Response of Central Giant Cell Granuloma to Denosumab: A 6-Year Prospective Observational Study.

Central giant cell granuloma (CGCG) is a rare lesion of the jaw occurring in young adults and adolescents. Surgery, the traditional mainstay of therapy, is associated with significant morbidity. Denosumab, a humanised monoclonal antibody to RANKL, is effective in a related entity, giant cell tumour of bone (GCTB), but experience in the more indolent CGCG is limited. This prospective observational study of all denosumab-treated CGCG at a tertiary referral centre (2015-2021) aimed to evaluate the safety, efficacy and recurrence risk using denosumab in CGCG at lower-frequency dosing than used for GCTB. All received standardised, time-limited courses of denosumab 120 mg with stepwise increase in dosing interval based on response. They were followed for up to 75 months using a radiation-minimising protocol: 3-monthly clinical, biochemical and radiological assessment (orthopantomograms, cone beam CT). Eight patients, median age 20.5 years [IQR 6], received 13 initial doses [IQR 10] of denosumab 120 mg. Radiologic response was seen after 5.5 doses [IQR 4.5]: ossification in all and size reduction in three. Recurrence occurred in four of seven completing therapy, observed 12 months post-cessation [IQR 6.5]. Larger baseline size, aggressive subtype and fewer than 12 initial doses were more common in the recurrence group. There was no osteonecrosis of the jaw. Hypocalcaemia occurred in one receiving modified dosing. This study represents the largest, most diverse cohort of denosumab-treated CGCG with the longest follow-up in literature. It demonstrates the efficacy of lower-frequency, time-restricted course of denosumab but highlights the risk of recurrence. Long-term follow-up is critical.

Calcifying epithelial odontogenic tumours: Collaborative study of 32 cases and review of literature.

OBJECTIVES: To analyse the occurrence of calcifying epithelial odontogenic tumours (CEOT) based on biopsy records from different Brazilian geographic regions and to contrast the data with a review of the literature. MATERIALS AND METHODS: A 2-step study was conducted. Step 1 consisted of a collaborative study of biopsies obtained from 1953 to 2017 at six Brazilian oral and maxillofacial pathology centres. Evaluation of 86,268 biopsy records was performed. Demographic and histopathological diagnosis data were assessed. In Step 2, a review of the literature of case reports and cases series of CEOT identified across five electronic databases was conducted. RESULTS: In the collaborative study, 32 cases of CEOT were evaluated. This figure represented 0.03% of the oral and maxillofacial lesions and 1.7% of all odontogenic tumours across the centres. Women in the fourth decade of life were more affected. CEOT occurred more in the mandible than in the maxilla (ratio 1.9:1). The review of the literature showed that Asian individuals were more affected by this neoplasm. CONCLUSIONS: Useful knowledge on the epidemiology, treatment and follow-up of CEOT has been provided. Demographic data and clinical features of the cases presented in this collaborative study were quite similar to those of studies reported worldwide.

Defining giant mandibular ameloblastomas - Is a separate clinical sub-entity warranted?

CONTEXT: The term giant mandibular ameloblastoma (GMAs) while being in popular usage in the medical literature remains largely equivocal. Although a few authors have in the past attempted to ascribe definite criteria to this entity, these are by and large arbitrary and without any benefit in decision-making or contributing to its management. AIMS: The aim of this study is to propose a set of objective criteria for GMAs that can be clinically correlated and thereby aid in the management of this entity. PATIENTS AND METHODS: Of a total of 16 patients with ameloblastoma of the mandible presenting at our institute from August 2012 to September 2016, 11 patients were identified as having GMAs as per the criteria proposed. RESULTS: The defects in the mandible following segmental resection ranged from 7 to 11.5 cm in length (mean: 9.3 cm). No clinical or radiological evidence of tumour recurrence was found during a mean follow-up period of 10.7 months (range: 2-28 months). CONCLUSIONS: Defining GMA based on objective inclusion and exclusion criteria allows segregation of these lesions, thereby helping to remove ambiguity, simplify decision-making and facilitate communication among treating reconstructive surgeons. Inclusion criteria include: (i) The segmental bone defect following resection with a minimum 1 cm margin of healthy bone should exceed 6 cm (ii) The segmental bone defect should involve the central mandibular segment.

Intraosseous schwannoma of the mandible: new case series, literature update, and proposal of a classification.

Intraosseous schwannoma of the mandible is rare, with diagnostic and therapeutic challenges. The aims of this study were to report new cases of intraosseous schwannoma of the mandible and to propose a clinical classification, providing suggestions for treatment methods. The cases of 13 patients treated at the authors' hospital and 86 cases reported previously in the literature were reviewed. The most common clinical feature was facial swelling (60/93). The rate of cortical thinning or expansion was 44.8% (43/96); widening of the inferior alveolar nerve canal on radiographs was observed in 15 patients.

Characterization of tumors of jaw: Additive value of contrast enhancement and dual-energy computed tomography.

BACKGROUND: Currently, the differentiation of jaw tumors is mainly based on the lesion's morphology rather than the enhancement characteristics, which are important in the differentiation of neoplasms across the body. There is a paucity of literature on the enhancement characteristics of jaw tumors. This is mainly because, even though computed tomography (CT) is used to evaluate these lesions, they are often imaged without intravenous contrast. This study hypothesised that the enhancement characteristics of the solid component of jaw tumors can aid in the differentiation of these lesions in addition to their morphology by dual-energy CT, therefore improving the ability to differentiate between various pathologies. AIM: To evaluate the role of contrast enhancement and dual-energy quantitative parameters in CT in the differentiation of jaw tumors. METHODS: Fifty-seven patients with jaw tumors underwent contrast-enhanced dual-energy CT. Morphological analysis of the tumor, including the enhancing solid component, was done, followed by quantitative analysis of iodine concentration (IC), water concentration (WC), HU, and normalized IC. The study population was divided into four subgroups based on histopathological analysis-central giant cell granuloma (CGCG), ameloblastoma, odontogenic keratocyst (OKC), and other jaw tumors. A one-way ANOVA test for parametric variables and the Kruskal-Wallis test for non-parametric variables were used. If significant differences were found, a series of independent t-tests or Mann-Whitney U tests were used. RESULTS: Ameloblastoma was the most common pathology (n = 20), followed by CGCG (n = 11) and OKC. CGCG showed a higher mean concentration of all quantitative parameters than ameloblastomas (P < 0.05). An IC threshold of 31.35 × 100 µg/cm3 had the maximum sensitivity (81.8%) and specificity (65%). Between ameloblastomas and OKC, the former showed a higher mean concentration of all quantitative parameters (P < 0.001), however when comparing unilocular ameloblastomas with OKCs, the latter showed significantly higher WC. Also, ameloblastoma had a higher IC and lower WC compared to "other jaw tumors" group. CONCLUSION: Enhancement characteristics of solid components combined with dual-energy parameters offer a more precise way to differentiate between jaw tumors.

Keratoameloblastoma of the lower jaw: A rare challenging entity.

Ameloblastoma is the second most common benign odontogenic tumor with various histopathologic features. Except for the unicystic type of ameloblastoma, the different microscopic patterns of this tumor show no significant correlation with long-term clinical behavior. During recent decades, additional challenging subtypes of ameloblastoma, including "Keratoameloblastoma" (KA), have been introduced in the literature. Here, we present a case of KA and discuss the important diagnostic microscopic features.

Conservative treatment of a unicystic ameloblastoma by marsupialization with a favorable response: A case report and review of the literature.

Ameloblastoma is a benign tumor of odontogenic epithelium which is slow growing, locally invasive, expansive that may result with asymmetries of the face. Conservative treatment of odontogenic tumors with marsupialization is not common but can be done successfully in those with cystic pattern. The aim of this case and literature review is to propose marsupialization as an initial procedure for its treatment. We have presented a case of an ameloblastoma involving 56-year-old male patient. Orthopantomography and computed tomography showed the lesion extended between the right molar region and left molar region of mandible with both buccal and lingual expansion and root resorptions. On clinical examination, expansions of mandible and slight tooth mobilities were seen. An incisional biopsy was carried out and histopathologic examination revealed ameloblastoma although clinical features of lesion were more suggestive of cyst. Our case was treated by obturator marsupialization with a good healing. This case and review of the literature discusses the available treatment option according to macroscopic features of jaw lesions and emphasizes on the importance of the most conservative treatment option. Conservative treatment preserves integrity of bones while radical treatment can leave major cosmetic and functional sequelae such as pathologic fractures, complication with reconstruction plates.

Predictors of distress associated with altered appearance and function in people treated surgically for oral cancers: a cross-sectional study.

This cross-sectional study was performed to examine sources of variation in distress associated with altered appearance and fundamental functions in oral cancer patients at 2 months, 12-15 months, 24-36 months, and ≥ 5 years post-definitive treatment. Eligible patients completed six scales from the FACE-Q Head and Neck Cancer Module. Pre-specified regression models were used to examine sources of variation in study outcomes for 145 patients. Patient self-reports indicated that distress associated with altered appearance and fundamental functions was highly variable, and distress was present beyond 5 years post-definitive treatment in some patients. Associations between distress scores and time post-definitive treatment, reconstructive surgery, and adjuvant therapy were not statistically significant. There was, however, moderate to strong evidence against the null hypothesis of no association between eating distress scores and sex, primary cancer site, and T-stage; smiling distress scores and age and primary cancer site; appearance distress scores and geographical remoteness and primary cancer site; and speaking distress scores and primary cancer site. Primary cancer site was the only significant independent predictor of multiple distress scores. These findings suggest that predicting the psychological impact of oral cancer treatment remains a challenge for the multidisciplinary team. Screening and interventions for psychological distress are essential beyond the preoperative and acute care settings.

Chondromyxoid fibroma affecting the maxilla in a 1-year-old child: Immunohistochemical analysis and literature review.

Chondromyxoid fibroma (CMF) is a benign chondroid/myxoid matrix-producing tumor that often develops in the long bones of young adults. CMF is rarely reported in the craniofacial skeleton, with most cases presenting with bone erosion or destruction, which may lead to a misdiagnosis. To date, approximately 129 cases of CMF in the craniofacial region have been reported, with only three cases in patients aged less than 1 year. Of these 129 cases, only 34 affected the jaws. A 1-year-old boy presented with a mass in the left anterior maxilla, extending and compressing the ipsilateral nasal cavity. After surgical excision of the lesion, microscopy revealed spindle-to-stellate tumor cells surrounded by a predominant myxoid stroma containing focal slit-like vascular channels and hemorrhagic areas. Immunohistochemistry showed positivity for vimentin, CD10, and α-SMA (focal). The Ki-67 labeling index was 6%. CFM should be included in the differential diagnosis when assessing maxillary tumors in pediatric patients.

Prediction of ameloblastoma recurrence using random forest-a machine learning algorithm.

The purpose of this study was to investigate whether ameloblastoma with a high likelihood of recurrence can be predicted using random forest model, a machine learning algorithm. Data were collected from patients treated for ameloblastoma between 1999 and 2019 at the University of Hong Kong. Fourteen clinical parameters were used to grow the decision trees to classify patients with or without ameloblastoma recurrence in the follow-up period. The random forest algorithm was computed 100 times in the training cohort (n = 100) and verified in the testing cohort (n = 50). The receiver operating characteristic curve (ROC) and area under the curve (AUC) were used as the performance measurement of separability. One hundred and fifty patients (76 female, 74 male) were recruited, with a mean follow-up time of 103 months. Recurrence occurred in a total of 25 cases (16.7%) over the 20-year period. The AUC were calculated for the median and mean ROC curves; these were 0.777 and 0.825, respectively. The results showed that random forest model was able to predict recurrence of ameloblastoma with reliable accuracy. The four most important variables influencing ameloblastoma recurrence were the time elapsed from treatment, initial surgical treatment, tumour size, and radiographic presentation. This study provides insights into the detection of high-risk patient groups to monitor recurrence. Further application of random forest to other diseases could greatly benefit clinical decisions.

Metastasis to the oral and maxillofacial region. A systematic review.

OBJECTIVE: Metastasis to oral and maxillofacial region (MOMFR) is an unusual finding; representing between 1 and 1.5% of all malignancies in the maxillofacial region. A systematic review is presented to determine trends in presentation, diagnostic features, and patient outcome. METHODS: Searches of databases were carried out for papers reporting MOMFR. The variables were demographics, patient symptoms, tumor location, tumor size, histopathology, origin of the tumor, immunohistochemical studies, follow-up and survival. RESULTS: 696 cases were identified; 391 males, and 305 females. The most common race was white. The most common primary tumor for females was from breast 31.1% (n = 95), for males from lung 20.5% (n = 143). The most common location was the mandible 44.9% (n = 313), followed by gingival soft tissue 16.8% (n = 117). A frequent clinical symptom was pain with 17.5% (n = 122). The most common clinical presentation was a mass or tumor 37.4% (n = 260). The mean age was 58.8 years. The average time before diagnosis was 10.3 months, the mean follow-up after diagnosis was 13.1 months, and the average survival was 9.8 months. CONCLUSION: MOMFR shows a strong predilection for the posterior mandible, with a mass or tumor being the most common clinical presentation. They are frequently painful, and demonstrate a poor prognosis.

Ameloblastoma: An Updated Narrative Review of an Enigmatic Tumor.

Ameloblastoma is one of the most common benign odontogenic tumors of the jaw that constitutes about 10% of all tumors that arise in the mandible and maxilla. It is a slow-growing but locally invasive tumor that presents with painless swelling of the mandible or maxilla. The World Health Organization (WHO) classification of 2017 describes ameloblastomas of the following four types: ameloblastoma; unicystic ameloblastoma; extraosseous/peripheral ameloblastoma; and metastasizing ameloblastoma. The diagnosis of ameloblastoma requires computerized tomography (CT) imaging as well as a biopsy. A biopsy is helpful in differentiating ameloblastoma from ossifying fibroma, osteomyelitis, giant cell tumor, cystic fibrous dysplasia, myeloma, and sarcoma. The best treatment of ameloblastoma is aggressive en bloc resection with simultaneous reconstruction. The high recurrence rate and large tissue defects have been long-standing issues in the treatment of ameloblastoma. Recent molecular developments strongly suggest the possibility of targeted therapy with better outcomes in ameloblastomas. We present a detailed updated narrative review of our current understanding and management of this enigmatic tumor.

Parafibromin Abnormalities in Ossifying Fibroma.

Ossifying fibromas are very rare tumors that are sometimes seen as part of the hyperparathyroidism-jaw tumor syndrome (HPT-JT), which is caused by inactivating mutations of the HRPT2/CDC73 tumor suppressor gene. CDC73 mutations have been identified in a subset of sporadic cases but aberrant expression of the encoded protein, parafibromin, has not been demonstrated in ossifying fibroma. We sought to determine if loss of parafibromin regularly contributes to the development of sporadic, nonsyndromic ossifying fibroma. We examined a series of 9 ossifying fibromas, including ossifying, cemento-ossifying, and juvenile active variants, for parafibromin protein expression by immunohistochemistry and for CDC73 sequence abnormalities by Sanger sequencing and/or targeted AmpliSeq panel sequencing. Four ossifying fibromas showed a complete absence of nuclear parafibromin expression; loss of parafibromin expression was coupled with aberrant cytoplasmic parafibromin expression in 1 case. CDC73 mutations were detected in 2 cases with aberrant parafibromin expression. These results provide novel evidence, at the level of protein expression, that loss of the parathyroid CDC73/parafibromin tumor suppressor may play a role in the pathogenesis of a subset of ossifying fibromas.

Malignant transformation of calcifying epithelial odontogenic tumour with solitary pulmonary metastasis.

This report describes the management of a case of calcifying epithelial odontogenic tumour (CEOT) that underwent malignant transformation and metastasized to the lung. The solitary pulmonary metastasis was discovered incidentally on computed tomography (CT) imaging of the neck. It appears that only one previous case with proven pulmonary metastasis has been reported in the literature, which involved multiple pulmonary deposits managed with platinum chemotherapy. The long-term prognosis of metastatic CEOT is therefore unknown. In the case presented here, the patient was managed successfully with surgery alone. There is often diagnostic uncertainty because histological features of benign, recurrent, and malignant CEOT are not dissimilar. Ki-67 immunohistochemistry is helpful, as higher levels are more indicative of malignancy. We consider that in cases of suspected recurrent and malignant CEOT, CT imaging of the thorax and abdomen as part of follow-up may identify metastases early, resulting in earlier treatment, an improved prognosis, and reduced morbidity and mortality.

Effectiveness of marsupialisation and decompression on the reduction of cystic jaw lesions: a systematic review.

In this study, we aimed to systematically review and critically appraise the available literature concerning the effectiveness of marsupialisation and decompression on the reduction of cystic jaw lesions. The 'Preferred Reporting Items for Systematic Reviews and Meta-Analysis' guidelines were followed and the study protocol was registered at the 'International Prospective Register of Systematic Reviews' (CRD42019116099). Six main databases were searched: Embase, LILACS, PubMed, Scopus, The Cochrane Library, and Web of Science. Searches were complemented with three grey literature sources: Google Scholar, ProQuest, and Open Grey. Any reduction measures, compared with preoperative status or other procedures, were considered. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tool. Thirty-one studies were included, of which five were judged with low, 24 with moderate, and two with high risk of bias. Considering surgical approach, 20 studies assessed the decompression and 11 the marsupialisation technique. Most studies considered these techniques as preliminary treatments, followed by enucleation. From 1088 lesions found, most were odontogenic keratocysts (33.8%), followed by unicystic ameloblastomas (21.0%), dentigerous cysts (20.6%), and radicular cysts (8.4%). Large lesions and younger individuals frequently presented more favourable responses to treatment and anatomical location was not associated with lesion reduction overall. The intervention duration generally ranged between one to two years. In conclusion, marsupialisation and decompression were mostly considered as preliminary treatments, followed by enucleation. Lesion reduction was generally considered insufficient for these techniques to be used as definitive therapies, although benefits concerning the diminished invasiveness of the secondary surgery were often proposed.

Primordial odontogenic tumour: A systematic review of the common but also unusual features of this novel entity.

BACKGROUND: Primordial odontogenic tumour (POT) is a novel entity that was described in 2014 and that is included in the group of benign mixed epithelial and mesenchymal odontogenic tumours. In recent years, several papers have added new cases with some clinical and histopathological aspects that slightly differ from those described in the original report. The aim of this systematic review is to update all available data on POT published in the literature and to identify those features of the neoplasm that require further investigation. MATERIALS AND METHODS: A systematic review of literature was conducted using PubMed, Embase, Web of Science and Scopus. Additional sources were also checked. Publications reporting cases with enough clinicopathological information were included, without any time or language restrictions. Histopathological or radiological studies were considered for qualitative analysis. RESULTS: A total of 30 publications were included. Seventeen papers were used for quantitative analysis while 13 papers were used only for qualitative analysis. A total of 18 cases of POT were identified. Some clinical, radiographic, histopathological and therapeutic features were common in all reported cases, while other aspects of the neoplasm were inconsistent through published cases. This inconsistency was particularly remarkable when dealing with the histopathological features of the neoplasm. DISCUSSION: Some issues about POT remain unclear and deserve to be clarified by future reports. The description of the odontogenic epithelium covering the ectomesenchyme is often contradictory, while it remains debatable whether peripheral ameloblastic epithelial islands or hard dental tissue deposition can occasionally occur within the tumour.

Evaluation of biopsies of oral and maxillofacial lesions: a retrospective study.

OBJECTIVES: This study aimed to determine the prevalence of odontogenic cysts, tumors, and other lesions among reports in the archives of the Department of Oral and Maxillofacial Surgery at the Faculty of Dentistry affiliated with Kocaeli University collected over a four-year period. MATERIALS AND METHODS: In this retrospective study, patient records from the archive of the Department of Oral and Maxillofacial Surgery from 2014 to 2018 were reviewed. Patient demographic information (age and sex) and lesion location were recorded and analyzed. RESULTS: From a total of 475 files reviewed, odontogenic cyst was confirmed in 340 cases (71.6%), and odontogenic tumor was confirmed in 52 cases (10.9%). Regarding odontogenic cyst type, the most common was radicular cyst (216 cases), followed by dentigerous cyst (77 cases) and odontogenic keratocyst (23 cases). Among odontogenic tumors, the most frequent was odontoma (19 cases), followed by ossifying fibroma (18 cases) and ameloblastoma (9 cases). Giant cell granuloma was also reported in 35 cases. CONCLUSION: The distribution pattern of odontogenic cysts and tumors in our retrospective study is relatively similar to that reported in the literature. Complete clinical reports for final diagnosis of these lesions and routine follow-up examinations are very important for treatment.

Prevalence of odontogenic cysts and tumors associated with impacted third molars: A systematic review and meta-analysis.

PURPOSE: This systematic review aimed to investigate the prevalence of odontogenic cysts and tumors associated with impacted third molars (ITM). METHODS: Only studies that performed histopathological diagnosis of lesions were eligible for inclusion. Five main electronic and three grey literature databases were searched. Risk of bias (RoB) of included articles was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. RESULTS: From 1,300 studies identified, 16 met the inclusion criteria. Seven studies were classified as high, seven as moderate, and two as low RoB. The prevalence of odontogenic cysts and tumors associated with ITM was 5.3% (95%CI: 3.1%-8.1%) of ITM. Odontogenic cysts in particular were found in 4.4% (95%CI: 2.5-6.8%) of the extracted ITM, whilst odontogenic tumors in 0.5% (95%CI: 0.2-0.9%). The dentigerous cyst was mentioned in eleven studies with a pooled prevalence of 2.1% (95%CI: 1.4-3.1%). The odontogenic keratocyst was cited by nine studies and had a prevalence of 0.5% (95%CI: 0.2-0.7%). The radicular cyst was mentioned only in three articles and the pooled prevalence was 4.7% (95%CI: 0.0-19.4%) CONCLUSION: Odontogenic cysts and tumors were found in 5.3% of ITM extracted. The most common lesions were the radicular cyst, dentigerous cyst, and odontogenic keratocyst.