Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Odontogenic and Maxillofacial Bone Tumors

Cone-beam computed tomography imaging of benign odontogenic lesions in the maxilla: A report of 2 cases

Odontogenic tumors are slow-growing and generally nonaggressive; however, aggressive characteristics appear to exist in particular tumors. The author reports two cases of benign odontogenic lesions at the anterior maxilla. A 44-year-old woman came to an oral-maxillofacial surgeon with a complaint of asymptomatic swelling of the left anterior region of the maxilla 15 years ago, which started gently but gradually increased over time. The patient experienced a physical injury 15 years ago, resulting in the loss of the upper left front teeth. In the other case, a 50-year-old woman complained for 5 years about a little swelling in her left anterior maxilla that became larger over time without causing any discomfort or pain. The Cone-beam computed tomography (CBCT) exam revealed a partially multilocular radiopaque mixed radiolucent lesion in the anterior maxilla, with margins that are both well-defined and ill-defined. Both display features of infiltrative, expansive, and moderately aggressive growths, leading to the erosion and perforation of the cortical plates in the buccal and palatal regions. Based on the biopsy results, both samples showed similar findings, specifically a benign odontogenic lesion, likely desmoplastic ameloblastoma, and squamous odontogenic tumor without any atypic cells or malignancy. This study aims to further our understanding of the clinical and radiological features of these patients and emphasize the importance of investigating specific lesions as potential diagnoses.

Unicystic ameloblastoma: Clinico-radiological and histopathological correlation with management

Unicystic ameloblastoma is a distinct entity of ameloblastoma characterized by slow growth and locally aggressive behavior. This retrospective study aimed to assess the efficacy of different treatment modalities of unicystic ameloblastoma, focusing on clinico-radiological and histopathological features. Data from patients diagnosed with unicystic ameloblastoma were retrospectively analyzed. Patients were categorized into luminal and intraluminal (Group A) and mural (Group B) variants based on the Ackermann classification, which has a significant influence on their biological behavior, treatment approaches, and prognosis. Patients in Group A underwent enucleation with chemical cauterization, peripheral ostectomy, and iodoform packing, whereas those in Group B were treated with resection and reconstruction. Post-operatively, the patients were subjected to radiographic assessments via digital orthopantomogram at regular intervals. Because of the rarity of unicystic ameloblastoma, only 17 patients were included in the study (Group A: 9 patients; Group B: 8 patients), with a mean follow-up of 4.9 years (range: 1.4-11.8 years). The primary outcome measure was the absence of recurrence, which indicated treatment success. No patient in either group experienced recurrence within the follow-up period. This study provides evidence supporting the successful treatment of luminal and intraluminal variants of unicystic ameloblastoma in young individuals using a conservative approach. However, the more aggressive mural variant demonstrated favorable outcomes with radical treatment. These findings emphasize the importance of the Ackermann classification in guiding treatment decisions for unicystic ameloblastoma and contribute valuable insights into optimizing therapeutic strategies based on clinico-radiological and histopathological findings.

Morphological CBCT parameters for an accurate differentiation between nasopalatine duct cyst and the normal nasopalatine canal

BACKGROUND

The incisive foramen width was a traditional imaging criterion for diagnosing nasopalatine duct (NPD) cysts. Recent CBCT studies demonstrated significant dimensional variations of the nasopalatine canal, which raised questions about the accuracy of this criterion. This study investigated whether nasopalatine canal diameters assessed on CBCT images can accurately differentiate NPD cysts from normal nasopalatine canals.

METHODS

The study included 19 patients with NPD cysts (12 (63.2%) males, 7 (36.8%) females, mean age 44.7 ± 13.3), and a control group of 164 patients (72 (43.9%) males, 92 (56.1%) females, mean age 47.25 ± 17.74). CBCT images were retrospectively evaluated. The following nasopalatine canal diameters were measured on reference sagittal, coronal, and axial reformation images: nasal opening anteroposterior (AP) and mediolateral (ML) diameter, oral opening AP (APOO) and ML (MLOO) diameter, nasopalatine canal length, minimum ML (minML) diameter, anterior wall expansion (AWE), nasopalatine canal angle, and the mid-level AP diameter (midAP). All parameters were compared between groups. Discriminant functional analysis (DFA) was applied to detect CBCT parameters that best differentiate the NPD cyst from the normal canal.

RESULTS

Patients with NPD cyst had significantly greater values of APOO (7.06 ± 2.09 vs. 5.61 ± 1.70), MLOO (6.89 ± 2.95 vs. 3.48 ± 1.24), minML (2.88 ± 1.53 vs. 2.25 ± 1.09), AWE (2.15 ± 0.65 vs. 0.41 ± 0.67), and midAP (4.58 ± 1.61 vs. 2.48 ± 0.96). DFA showed MLOO, AWE, and midAP as the most accurate in distinguishing NPD cyst from the normal canal. When combined in the discriminant function equation X = 0.390·MLOO + 1.010·AWE + 0.288·midAP (cut score 1.669), the differentiation can be performed with a sensitivity and specificity of 98.8% and 76.9%, respectively.

CONCLUSION

NPD cysts can be accurately distinguished from the normal nasopalatine canal by measuring MLOO, AWE, and midAP diameter on CBCT images.

Loss of clear cell characteristics in aggressive clear cell odontogenic carcinoma: a case report

BACKGROUND

Clear cell odontogenic carcinoma (CCOC) is an odontogenic carcinoma characterized by sheets and islands of vacuolated and clear cells. The diagnosis of atypical CCOC can pose a challenge when tumor cells deviate from their characteristic clear morphology, even with the aid of genetic profiling for CCOC identification.

CASE PRESENTATION

In this manuscript, we detailed the inaugural instance of a recurrently recurring clear cell odontogenic carcinoma (CCOC) with pronounced squamous differentiation in a 64-year-old male. The primary tumor in this individual initially displayed a biphasic clear cell phenotype. However, subsequent to the third recurrence, the clear tumor cells were entirely supplanted by epidermoid cells characterized by eosinophilic cytoplasm, vesicular chromatin, and prominent nucleoli. Notable aggressive attributes such as necrosis, conspicuous cytological malignancy, perineural dissemination, and vascular invasion were noted. Additionally, the tumor progressed to manifest lung metastases. The tumor cells exhibited positive immunoreactivity for AE1/AE3, KRT19, Pan-CK, EMA, P40, P63, CK34βE12, and P53, while they tested negative for CK35βH11, KRT7, S-100, and neuroendocrine markers. The Ki-67 proliferation index was calculated at an average of 15%. Furthermore, FISH analysis unveiled the presence of the EWSR1::ATF1 gene fusion.

CONCLUSIONS

This case illustrated a rare and aggressive case of CCOC characterized by significant squamous differentiation upon recurrence of the tumor.

Conservative Approach in Managing Complex Odontogenic Lesions: A Case Report and Literature Review

Radicular cysts are among the most common odontogenic cystic lesions in the maxillofacial region. This case report details the management of a large radicular cyst in the anterior maxillary region of a 32-year-old female patient and includes a literature review on such cysts. The patient underwent cyst decompression, surgical enucleation, tooth extractions, root canal treatments, periapical curettage, and prosthetic rehabilitation. This study underscores the effectiveness of conservative approaches, such as decompression, in reducing cyst size and highlights the importance of individualized treatment plans for achieving optimal outcomes and preventing recurrence. Collaborative efforts between clinicians and multidisciplinary teams are crucial for managing radicular cysts and ensuring long-term oral health for patients.

Use of a Penrose Drain for Decompression of a Large Periapical Lesion: A Case Report With 4.5-Year Follow-up

Managing large cyst-like periapical lesions poses significant challenges, especially when nonsurgical treatment or retreatment options are ineffective. Despite its efficacy, decompression remains an underutilized minimally invasive alternative in modern dentistry. This case report describes the use of a Penrose drain for decompression following aspiration and irrigation to manage a large periapical lesion associated with a 56-year-old man's maxillary lateral incisor. The lesion had caused thinning and perforation of the facial and palatal cortical plates, as well as the inferior border of the nasal fossa. Cone-beam computed tomography was used to evaluate the lesion preoperatively and to assess the healing progress postoperatively. Complete 3-dimensional healing was observed after a subsequent root-end surgery performed 3.5 years post-decompression. This report suggests that decompression using a Penrose drain in combination with aspiration and irrigation could be a simple but effective modality for managing large cyst-like periapical lesions when nonsurgical endodontics are attempted and deemed ineffective.

Automatic Annotation Diagnostic Framework for Nasopharyngeal Carcinoma via Pathology-Fidelity GAN and Prior-Driven Classification

Non-keratinizing carcinoma is the most common subtype of nasopharyngeal carcinoma (NPC). Its poorly differentiated tumor cells and complex microenvironment present challenges to pathological diagnosis. AI-based pathological models have demonstrated potential in diagnosing NPC, but the reliance on costly manual annotation hinders development. To address the challenges, this paper proposes a deep learning-based framework for diagnosing NPC without manual annotation. The framework includes a novel unpaired generative network and a prior-driven image classification system. With pathology-fidelity constraints, the generative network achieves accurate digital staining from H&E to EBER images. The classification system leverages staining specificity and pathological prior knowledge to annotate training data automatically and to classify images for NPC diagnosis. This work used 232 cases for study. The experimental results show that the classification system reached a 99.59% accuracy in classifying EBER images, which closely matched the diagnostic results of pathologists. Utilizing PF-GAN as the backbone of the framework, the system attained a specificity of 0.8826 in generating EBER images, markedly outperforming that of other GANs (0.6137, 0.5815). Furthermore, the F1-Score of the framework for patch level diagnosis was 0.9143, exceeding those of fully supervised models (0.9103, 0.8777). To further validate its clinical efficacy, the framework was compared with experienced pathologists at the WSI level, showing comparable NPC diagnosis performance. This low-cost and precise diagnostic framework optimizes the early pathological diagnosis method for NPC and provides an innovative strategic direction for AI-based cancer diagnosis.

Characterization of stromal calcifications in odontogenic keratocyst: a multicentric study

Odontogenic keratocysts (OKCs) are locally aggressive cysts that exhibit typical histopathological features and have a propensity for recurrence. Though histological variations are observed in OKCs, hard tissue formation and metaplastic changes are rare, and the underlying pathogenesis is not well understood. This study aimed to characterize stromal calcifications and analyze their association with odontogenic components in non-syndromic and syndrome-associated cases of OKCs. We analyzed 153 cases of OKCs from healthcare institutes in India and Japan. The epithelial and stromal features were evaluated, and the relationship of calcifications with odontogenic rests was determined. Immunohistochemistry for cytokeratin-19 and special stains including Masson Trichrome and Van Gieson, were used for identification of odontogenic rests and calcifications respectively. Stromal calcifications were observed in 29.41% OKCs. The calcification patterns included irregular dystrophic, dentinoid with linear or calcospherite-type mineralization, and psammoma calcifications. Psammoma and dentinoid calcifications were found in the proximity of cytokeratin-19-positive odontogenic rests or satellite cysts, whereas majority cases with dystrophic calcifications did not exhibit co-localization with stromal odontogenic components. Distinct patterns of calcifications were observed in OKCs. Calcifications found in proximity of the odontogenic rests were possibly indicative of an inductive or host-mediated response.

Solitary ameloblastic fibroma with impacted teeth: A case report

This case report aimed to describe a rare benign mandibular tumour and assess the outcomes of the most recent reviews, between January 2017 and August 2023. Presenting a detailed clinical case, this study advances our understanding of the diagnostic and therapeutic aspects, ultimately improving the management of similar cases in clinical practice. Orthopantomogram (OPG) revealed a well-defined unilocular radiolucency extending from the midline of the ramus and teeth 47 and 48 were submerged at the base of the mandible. In the presented case, a PLANMECA ROMEXIS PROMAX® three-dimensional (3D) maximum (MAX) cone-beam computed tomography (CBCT) device was used for the 3D examination. An intraoral approach was preferred and the tumour was removed in toto by creating a bone window using a W&H® Dentalwerk Bürmoos GmbH Piezomed piezoelectric device, and the bone plates were fixed with 4 MEDARTIS® microplates, with a primary flap closure. A PANORAMIC 1000, 3DHISTECH Ltd® device was employed for the histological investigation. Odontogenic tumours are rare and typically asymptomatic, often discovered incidentally during routine radiographic examinations. Most of these benign lesions heal well after complete excision and require long-term follow-up. Once diagnosed, ameloblastic fibroma (AF) should be treated immediately to avoid malignant transformation.

Clinical and radiological documentation of complete remodeling of the mandibular bone after the enucleation of a large odontogenic keratocyst: 15 years follow-up of a unique case - A case report

INTRODUCTION AND IMPORTANCE

Odontogenic keratocysts (OKC) are benign intraosseous cysts with expansive growth. They account for approximately 7.8 % of all jaw cysts and have a high recurrence rate. Herein, we present a minimally invasive approach for the surgical treatment of a remarkable variation of OKC with a 15-year radiological and clinical follow-up.

PRESENTATION OF THE CASE

We present the case of a 42-year-old female patient with a large cyst in the mandible between teeth 35 and 45, who reported spontaneous swelling and paresthesia of the lower lip. Radiological imaging is crucial for treatment planning. The cyst was surgically treated with a single enucleation combined with adjuvant therapy to minimise recurrence. A titanium plate was inserted because of the size of the defect. Recurrence was observed one year later and treated with single enucleation and adjuvant therapy. After 15 years, complete healing, no signs of recurrence, and complete remodeling of the mandible were observed.

CLINICAL DISCUSSION

The treatment of OKC remains the subject of varying approaches in the literature due to the lack of established general guidelines. One treatment option is single enucleation combined with adjuvant therapy to minimise recurrence, which can result in complete clinical and radiological remodeling of the bone.

CONCLUSION

Direct enucleation combined with adjuvant therapy is a practical approach for treating large OKCs. It is associated with less morbidity and burden on the patient than enucleation with prior decompression or radical resection. Additionally, it shows no deficits in bone defect healing.

The Curious Case of a 'Maverick' Cementoblastoma!

Introduction

The Cementoblastoma is a benign ectomesenchymal odontogenic neoplasm of the jaw, arising from an exuberant production of cemental tissue continuous with the roots of teeth (usually mandibular posteriors), resulting in a calcified mass adherent with the root apices.

Case Presentation

A curious case of a large Cementoblastoma, the size and shape of a ping pong ball, is presented, the first of its kind ever reported to involve the internal / medial / lingual aspect of the mandible, and presenting with unusual and deviant features.

Discussion & Conclusion

The Cementoblastoma is usually associated with certain inherent and pathognomonic features, making it rather straightforward to identify and diagnose. Strikingly uncharacteristic clinical, radiographic and histologic attributes presented in this case, made this 'out of the ordinary' and 'Maverick'-like Cementoblastoma, arduous to diagnose, nevertheless, making it an interesting, informative and curious Case Study. This report has brought to light for the first time, several new facets of the Cementoblastoma.

A rare case report of ameloblastic fibrodentinoma with imaging features in a pediatric patient

Ameloblastic fibrodentinoma (AFD) is a rare benign odontogenic tumor that resembles an ameloblastic fibroma with dysplastic dentin. This report presents a rare case of mandibular AFD with imaging features in a young patient. Panoramic radiography and computed tomography revealed a well-defined lesion with internal septa and calcified foci, causing inferior displacement of the adjacent molars as well as buccolingual cortical thinning and expansion of the posterior mandible. The lesion was surgically removed via mass excision, and the involved tooth was extracted under general anesthesia. During the 5-year follow-up period, no evidence of recurrence was observed. Radiologic features of AFD typically reveal a moderately to well-defined mixed lesion with varying degrees of radiopacity, reflecting the extent of dentin formation. Radiologists should consider AFD in the differential diagnosis when encountering a multilocular lesion with little dense radiopacity, particularly if it is associated with delayed eruption, impaction, or absence of involved teeth, on radiographic images of young patients.

Juvenile trabecular ossifying fibroma associated with central giant cell granuloma and aneurysmal bone cyst like changes - A triple hybrid tumour? Or a pathologic sequelae?

Hybrid tumours encompass lesions containing two or more pathologic entities. The pathogenesis of these lesions is barely understood and described. Juvenile trabecular ossifying fibroma (JTOF) is a benign but locally aggressive fibro-osseous neoplasm commonly affecting the maxilla of the adolescent age group. Hybrid lesions of JTOF have been reported along with central giant cell granuloma (CGCG), aneurysmal bone cyst (ABC) and traumatic bone cyst, respectively. However, the co-occurrence of JTOF with CGCG and ABC in a single patient has not yet been reported in the literature, hence, making ours the first case report of this kind. Theories describing the pathogenesis of this rare phenomenon have also been proposed and elaborated.

Reticular Myxoid Odontogenic Neoplasm with Novel STRN::ALK Fusion: Report of 2 Cases in 3-Year-Old Males

Odontogenic tumors represent a collection of entities ranging from hamartomas to destructive benign and malignant neoplasms. Occasionally, pathologists encounter gnathic lesions which clearly exhibit an odontogenic origin but do not fit within the confines of established diagnoses. Here, we describe two such odontogenic tumors, both affecting 3-year-old males. Each case presented as a destructive, radiolucent mandibular lesion composed of mesenchymal cells, some with unique multi-lobed nuclei, frequently arranged in a reticular pattern and supported by a myxoid stroma with focal laminations. Production of odontogenic hard tissues was also seen. Because of their unique microscopic features, both cases were investigated by next-generation sequencing and found to harbor the same STRN::ALK oncogene fusion. To our knowledge, these cases represent the first report of an odontogenic tumor with a STRN::ALK gene rearrangement. We propose the possibility that this neoplasm could be separate from other known odontogenic tumors. Both patients were treated with surgical resection and reconstruction. The prognosis of patients with this entity is currently uncertain but shall become more apparent over time as more cases are identified and followed.

Curettage combined with decompression for the treatment of ameloblastoma in children: report of two cases

BACKGROUND

Ameloblastoma (AM) is the most common benign odontogenic tumor, which is more often detected in the mandible than maxilla, especially the mandibular body and mandibular angle. Pediatric AM is a rare disease, especially in patients aged 10 and younger. Compared with the mainstream osteotomy and reconstructive surgery for adult ameloblastoma, there is more room for discussion in the treatment of pediatric ameloblastoma. The postoperative functional and psychological influence can not be ignored. Especially for children in the period of growth and development, an osteotomy is often challenging to be accepted by their parents. We report two patients with ameloblastoma under 10 years old who are treated with curettage and fenestration, which is a beneficial method for children with ameloblastoma.

CASE PRESENTATION

We present two cases of classic ameloblastoma in children. We describe in detail the patients' characteristics, treatment processes, and follow-up result. The bone formation and reconstruction in the lesion area after fenestration decompression and curettage are recorded at every clinic review. The surgical details and principles of curettage and decompression are also described and discussed. The two patients have good bone shape recovery and no recurrence.

CONCLUSIONS

Children are in the growth and development period and possess an extremely strong ability of bone formation and reconstruction. Based on the principles of minimally invasive and functional preservation, we believe that curettage combined with decompression can be the first choice for treating AM in children, especially for mandibular lesions.

Malignant transformation of primary ameloblastoma of skull: case report and review of current literature

Background

Since 1964, there has been a scarcity of reported cases of primary ameloblastoma (AM) or ameloblastic carcinoma (AMCa) of the skull. The clinical presentation and distinctive features of this uncommon condition at specific anatomical sites remain unclear. We report a case of malignant transformation of a primary AM of the skull situated in the frontal-temporal-parietal region and highlight its similarities to other cases reported in the literature.

Clinical presentation

A 53-year-old female patient presented with a 20-day history of headaches and bilateral lower limb weakness for 10 days. Physical examination revealed slow and unsteady gait. An occupying lesion was observed in the right frontal-temporal-parietal region of the skull on the Cranial imaging. A right cranial bone tumor margin expansion resection was performed. The patient's motor functions recovered normally after surgery. Postoperative imaging examinations showed10 tumor resection. Follow-up imaging examinations showed tumor recurrence. The patient underwent resection of the recurrent tumor. Postoperative pathological analysis revealed malignant transformation of the AM.Follow-up imaging examinations showed tumor recurrence again. The patient was admitted for stereotactic radiotherapy. Follow-up imaging examinations demonstrated no evidence of tumor recurrence and subsequent chest CT revealed no signs of metastasis.

Conclusion

Primary AM or AMCa of the skull is increasingly being described in the literature, but detailed reports on the malignant transformation of primary AM of the skull are lacking. The pathogenesis of this condition remains unclear. Aggressive treatment and close follow-up may be crucial for preventing disease recurrence and malignant transformation.

Prognostic value of the expression and localization of cell proliferation and apoptosis markers in unicystic ameloblastomas

The aim of this study was to verify whether the expression of cell proliferation and apoptosis markers in different types of unicystic ameloblastoma (UA) is associated with the location of neoplastic cells. Immunohistochemical study with a sample of 32 cases of UA, 11 cases of conventional ameloblastoma (CAM) and ten dental follicles (DF) cases was performed. Cell proliferation was assessed using Ki-67 status, and apoptosis by caspase-3 expression. Mural UA (MUA) showed a higher immunostaining of Ki-67 (p < 0.05) and a lower immunostaining of Caspase-3 (p < 0.05) compared with luminal and intraluminal subtypes of UA and CAM. The neoplastic cells of the MUA's cystic capsule showed a higher expression of Ki-67 protein (p < 0.0001) and a lower expression of Caspase-3 (p < 0.0001) compared with the lumen. DF showed lower Ki-67 and Caspase-3 immunostaining (p < 0.05) than neoplasms. The higher immunoexpression of Ki-67 and the lower immunoexpression of Caspase-3 in MUA, in the parenchyma cells within the cystic capsule, suggest an association between the biological behaviour and location of neoplastic cells in a tumour.

Periapical Cemento-Osseous Dysplasia: A Journey from Diagnostic Dilemma to Accurate Diagnosis with Use of 3D Imaging

Cemento-osseous dysplasia is a subgroup of fibro-osseous dysplasia commonly invading the tooth-bearing regions of the mandible quite often. These bony pathologies are asymptomatic and are seen on radiographs as an incidental finding. Accurate diagnosis of periapical cemento-osseous dysplasia is very crucial as it will help in the proper management of the patient as the incorrect diagnosis can lead to the unnecessary endodontic treatment of the concerned teeth as it may be misdiagnosed as a periapical pathology. We describe a case of periapical cemento-osseous dysplasia in which a 52-year-old woman had been experiencing discomfort in the right mental area of her mandible for the previous 6 months and had finally sought help at the outpatient department. This case study aims to highlight the significance of making an accurate diagnosis of cemento-osseous dysplasias in the tooth-bearing area.

Differential Profile of Primary and Recurrent Ameloblastomas Among Afro-descendants and Non-Afro-descendants-a Systematic Review

Ameloblastoma is an aggressively growing jaw tumor with high recurrent properties. Reports on global and racial distribution of ameloblastoma are variable and inconclusive. The role of race and ethnicity on ameloblastoma growth characteristics, genetic mutational profile, and recurrence is also still unclear. The primary aim of this systematic review was to assess genetic, racial, and ethnic distribution of primary and recurrent ameloblastoma from published literature. The secondary aim was to assess potential correlations between ethnicity, genetic mutation, and disparities in ameloblastoma treatment outcomes in Afro-descendants and non-Afro-descendants. Twenty-three eligible articles were selected based on preferred reporting items for systematic review and meta-analysis (PRISMA), and a total of 169 ameloblastoma cases were evaluated. Data on patient demographics, ameloblastoma growth characteristics, and genetic status were collected for quantitative analysis. Among a total of 169 ameloblastoma cases, Afro-descendant patients had higher primary and recurrent ameloblastomas at 15.5% and 4.7% respectively compared to non-Afro-descendant at 10.7% and 1.8% respectively. Additionally, BRAF V600E was positively associated with 48.8% of all ameloblastomas and strong predilection for Afro-descendants. Despite the paucity of information on genetic profile of ameloblastomas in the Afro-descendant patient cohort, this ethnic group still accounted for 2.95% of all BRAF V600E-positive tumors. These suggest that Afro-descendants are understudied regarding ameloblastoma characteristics, genetic profile, and recurrence profile. Mutational analysis of ameloblastoma tumors in Afro-descendants should be promoted.

Recurrence Patterns of Odontogenic Keratocysts in Syndromic and Non-Syndromic Patients

Purpose

Odontogenic keratocysts (OKCs) have high recurrence rates. We aimed to identify recurrence patterns in OKCs and the onset of second primary OKCs in non-syndromic and syndromic patients.

Material and Methods

Patients with OKCs reporting to our department from 1998 to 2021 (23 years) were retrospectively evaluated using demographic, clinical (age, sex, location, and size), histopathological, radiographic, and treatment data. All patients were followed-up for > 3 years and evaluated for OKC recurrence. Patients with naevoid basal cell carcinoma syndrome (NBCCS) were evaluated separately.

Results

We included 38 and 13 patients in the non-syndromic and syndromic OKC groups, respectively. The recurrence rates were 15.8 and 21.4% in the non-syndromic and syndromic groups, respectively; 8.9% of patients exhibited a second recurrence and 1.8% a third recurrence. No second primary OKCs were observed in the non-syndromic group; 76.9% of patients in the syndromic group developed at least one.

Conclusion

We found a higher recurrence rate in patients with NBCCS compared with patients with non-syndromic OKCs (21.4 versus 15.8%). The probability of developing a second primary OKC in patients with NBCCS was higher compared with that in patients with non-syndromic OKCs (76.9 versus 0%). No statistically significant risk factors for OKC recurrence were identified.

Comparison of Five Different Treatment Approaches of Mandibular Keratocystic Odontogenic Keratocyst (OKC): A Retrospective Recurrence Analysis of Clinical and Radiographic Parameters

The odontogenic keratocyst (OKC) is a benign but locally aggressive growing lesion that infiltrates the bone and surrounding tissue. It is characterized by high rates of recurrence along with rapid growth. Different forms of partly successful treatment therapies are reported. The retrospective study at hand examined 114 patients with OKC treated over a period of 20 years. Data extracted includes gender, age, location, previous treatment for the lesion, surgery, outcome, recurrence rate and follow-up. 63.1% of the patients underwent cystectomy, 22.5% by cystectomy and carnoy solution, 7.2% by cystectomy, and curettage, 4.5% by cystostomy and 2.7% by partial resection. In this study, no significant differences could be observed regarding the surgical method. Most recurrences occurred with 91.9% in the mandible with an average size of 5.5 cm2 and increased in women. Within a mean follow-up time of 3.6 years the recurrence rate was 36.9%, on average after 36 months. Recurrences were most frequently diagnosed at the age of 31-50 (43.9%). Despite numerous studies, there is still no unanimous opinion on an effective therapy for OKC. However, precise resection of OKC can be facilitated by preoperative 3D-imaging and virtual planning.

Spatial transcriptomic interrogation of the tumour-stroma boundary in a 3D engineered model of ameloblastoma

Stromal cells are key components of the tumour microenvironment (TME) and their incorporation into 3D engineered tumour-stroma models is essential for tumour mimicry. By engineering tumouroids with distinct tumour and stromal compartments, it has been possible to identify how gene expression of tumour cells is altered and influenced by the presence of different stromal cells. Ameloblastoma is a benign epithelial tumour of the jawbone. In engineered, multi-compartment tumouroids spatial transcriptomics revealed an upregulation of oncogenes in the ameloblastoma transcriptome where osteoblasts were present in the stromal compartment (bone stroma). Where a gingival fibroblast stroma was engineered, the ameloblastoma tumour transcriptome revealed increased matrix remodelling genes. This study provides evidence to show the stromal-specific effect on tumour behaviour and illustrates the importance of engineering biologically relevant stroma for engineered tumour models. Our novel results show that an engineered fibroblast stroma causes the upregulation of matrix remodelling genes in ameloblastoma which directly correlates to measured invasion in the model. In contrast the presence of a bone stroma increases the expression of oncogenes by ameloblastoma cells.

Recurrence and malignant risk of ameloblastoma: A demographic study of 1626 cases from east China

BACKGROUND

Ameloblastoma is characterized by aggressive nature, high recurrence rate, occasional malignant transformation, but recurrence and malignant incidence of ameloblastoma are not yet addressed by a large-scale case series study.

MATERIALS AND METHODS

This study provided a detailed description of the relationship between demographic characteristics and recurrence and malignant cases with different clinical types of ameloblastoma (n = 1626).

RESULTS

The overall incidence of recurrence and malignancy was 17.2 % and 3.4 %, respectively. Notably, we observed that there were multiple recurrent episodes (mean time, 24.3-28.7 months) among ameloblastoma patients. Multivariate analysis revealed that age of > 45 years (odds ratios (OR), 2.10; 95 % confidence interval (CI), 1.17-3.76), male (OR, 3.24; 95 %CI, 1.49-6.99), maxilla (OR, 5.58; 95 %CI, 3.11-10.0), and pre-existing recurrence (OR, 3.79; 95 %CI, 2.05-7.01) as independent factors were associated significantly with increased risk of malignancy.

CONCLUSION

Identification of the clinical factors responsible for increased risk of malignancy provides better insight in management planning for ameloblastoma.

Ameloblastoma of the Mandible in a 16-Year-Old Female-Case Report

Ameloblastoma is a benign epithelial tumor that has aggressive, destructive and unlimited growth potential, having the capacity for recurrence and malignant transformation. Regarding the symptoms and clinical signs, the presentation of ameloblastoma is poor. In children and young people, ameloblastoma can be difficult to diagnose, because it mimics other benign lesions. Its diagnosis requires a combination of imaging data, histopathological analysis and molecular tests. The methods of treatment consist of radical surgery (segmental resection) and conservative treatments (enucleation with bone curettage). The particularity of the presented case is represented by the late request for medical consultation, a direct consequence of the measures implemented to prevent and control the spread of COVID-19.

Cemento-ossifying fibroma resection combined with heterotopic canine autotransplantation: a case report

Cemento-ossifying fibroma (COF) is a mesenchymal benign odontogenic tumor, which may lead to impacted or ectopic permanent teeth. Autotransplantation of teeth is a surgical process, in which a tooth is transplanted from one position to another in the same individual. This method can effectively restore the patient's mastication and aesthetics and is feasible in replacing missing teeth. This study reports a case of simultaneous COF resection combined with heterotopic canine autotransplantation to repair dentition defect, which effectively promotes the restoration of bone continuity and stability and achieves immediate and long-term aesthetic function requirements.

The diagnostic yield of preoperative screening for oral cancer in dogs over 15 years, part 2: distant screening

OBJECTIVE

Determine diagnostic yield of chest, abdomen, and 4-site screening to diagnose metastatic disease and secondary diseases of prognostic significance in dogs with oral cancer.

SAMPLE

Medical records from 381 dogs with histologically confirmed oral tumors that underwent preoperative screening were retrospectively reviewed.

RESULTS

Thoracic metastasis was diagnosed in 4.9% (0.9% odontogenic, 6.5% nonodontogenic) of oral tumors. Oral malignant melanoma and multilobular osteochondrosarcoma were most at risk. Abdominal metastasis was diagnosed in 2% of oral tumors (0% odontogenic, 3.1% nonodontogenic) and cytologically confirmed in 2 cases (0.6% [2/295)] of all abdominal ultrasounds (AUS) 5.5% [2/36] of all AUS that had cytology). Both cases had oral malignant melanoma. Incidental disease was diagnosed in 53.1% and 81.3% of thoracic and abdominal screenings, respectively. Major findings were more common in AUS (7.8%) compared to thoracic screening (1.9%). The prevalence of incidental findings was similar for odontogenic and nonodontogenic tumors. Both metastasis and major findings were diagnosed more commonly with thoracic CT compared to radiographs. Metastasis or a major finding of prognostic significance was diagnosed in at least 1 test in 27.8% of patients that had head CT, lymph node cytology, thoracic screening, and AUS (n = 115).

CLINICAL RELEVANCE

Major incidental findings were more commonly detected with AUS and were diagnosed in 1 in every 12 patients. However, metastatic disease was most commonly detected with thoracic screening. When all 4 screening tests are performed, there is an approximately 1 in 4 chance of diagnosing metastasis or major significant disease regardless of tumor type.

Clinical outcome following conservative treatment of 58 mandibular ameloblastoma patients: a retrospective study

The aim of this study was to retrospectively analyze the surgical outcome of the patients with mandibular ameloblastoma (MA) with intact inferior cortex and the lingual cortex of the mandible, treated with conservative management in the form of enucleation with peripheral ostectomy, mechanical curettage, chemical cauterization, dredging, and marsupialization. The patients were included with the diagnosis of MA between the age group of 14 to 60 years with their computed tomography (CT) scans showing intact inferior cortex and the lingual cortex of the mandibular walls. Out of 96 cases of ameloblastoma, 58 (61%) were in mandible and 38 (39%) cases in maxilla. We analyzed these 58 patients retrospectively which were operated conservatively between January 2009 and December 2018. The treatment protocol for all the solid variants and the unicystic variants with intact buccal, inferior, and the lingual cortex was enucleation with peripheral ostectomy followed by mechanical curettage, chemical cauterization, and subsequent dredging. This was performed in 90% (n = 52) cases, whereas the treatment protocol for unicystic variants with perforated buccal cortex and intact inferior and lingual cortex was marsupialization followed by the enucleation with peripheral ostectomy, mechanical curettage, chemical cauterization, and subsequent dredging which was performed in 10% (n = 6) cases. Chi square test was applied to the effectiveness of conservative management as outcome variable. The new bone formation along with bony trabeculae was found in 96.6% (n = 56) of the cases. Recurrence was noted in 3.44% (n = 2) of the cases. A p value was 0.001, thus suggesting statistically highly significant result. On the basis of present study, though we can conclude that the MA with the intact inferior and the lingual cortex can be managed effectively with conservative treatment with long term regular follow up, still we would caution that the reader must use their best clinical judgement based on latest available data. For some patients, returning to clinic frequently and undergoing multiple minor procedures may not be suitable to be considered the best, whereas resection and reconstruction may be deemed more appropriate.

Curettage combined with bone cavity opening reduces recurrence of the mandibular conventional ameloblastoma and effectively preserves the mandible: a retrospective study

BACKGROUND

Patients with mandibular conventional ameloblastoma undergoing radical surgical treatment experience greater trauma and often find it challenging to accept, whereas conservative therapy is associated with a higher recurrence rate. In this study, we have improved traditional conservative treatment for mandibular conventional ameloblastoma by curettage combined with bone cavity opening (Cur/BCO). This retrospective study aimed to evaluate the effectiveness of the Cur/BCO treatment by comparing its recurrence rate and bone mineral density (BMD) growth rate with the traditional conservative treatment approach.

METHODS

A total of 40 patients, meeting the study's inclusion and exclusion criteria from 2012 to 2020, were screened, with 20 in the modified group and 20 in the traditional group. ImageJ (RRID: SCR_003070) software was employed for measuring image indices. All data were analyzed using T-test, Chi-square test and Fisher exact test in SPSS 26.0 (p = 0.05).

RESULTS

The incidence of recurrence was significantly lower in the modified group, at only 5%, compared to 35% in the traditional group (p < 0.05). Regarding bone mineral density (BMD) growth rate, the average value in the modified group was 0.0862 ± 0.2302 (/month), significantly higher than the average value of 0.0608 ± 0.2474 (/month) in the traditional group (p < 0.05).

CONCLUSIONS

In this study, it was found that the recurrence rate of the modified conservative treatment (Cur/BCO) was lower than that of the traditional conservative treatment for managing mandibular conventional ameloblastoma. Furthermore, the BMD growth rate was quicker in the modified group. Thus, Cur/BCO could be considered as a viable option for the conservative treatment of mandibular conventional ameloblastoma.

Odontogenic tumours in a Chilean population: a retrospective study of 544 cases based on 2022 WHO classification

BACKGROUND

Odontogenic tumours are infrequent lesions. Studies on the frequency of odontogenic tumours from Latin America are scarce. This work aimed to determine the relative frequency of odontogenic tumours in a Chilean population using the 2022 World Health Organization classification.

MATERIAL AND METHODS

This is a case series retrospective study. We reviewed 35,530 samples from 1975 to 2022 from the Oral Pathology Referral Institute and the Pathological Anatomy Service, Faculty of Dentistry, University of Chile. We utilized the 2022 World Health Organization classification for histological typification.

RESULTS

According to 2022 World Health Organization classification, 544 odontogenic tumours were confirmed. The most frequent odontogenic tumours were: odontoma (n=241; 44.3%), ameloblastoma (n=109; 20.0%) and cemento-ossifying fibroma (n=71; 13.1%). Benign odontogenic tumours corresponded to 538 cases (98.9%) and malignant tumours were only six cases (1.1%).

CONCLUSIONS

In our population, odontoma was the most frequent odontogenic tumour followed by ameloblastoma and cemento-ossifying fibroma. Malignant odontogenic tumours were very rare. The results of this study are similar to reports from America, but there are some differences concerning the data from Africa and Asia.

Does BRAF mutation status and related clinicopathological factors affect the recurrence rate of ameloblastoma? A systematic review, meta-analysis and metaregression

OBJECTIVES

This review aims to analyse the recurrence rate in BRAFv600e+ and BRAFv600e- ameloblastomas and explore its association with clinicopathological variables.

METHODS

A comprehensive search was conducted using databases including PubMed, Embase, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, Google Scholar and grey literature, without any limitation on start date or language up to 20 June 2023. A random effect meta-analysis was conducted and Metaregression analyses were performed based on available clinicopathological factors.

RESULTS

Fifteen studies met the criteria for meta-analysis of outcomes. There was no significant difference in overall recurrence rates between the two groups (risk difference = 0.001, p-value = 0.987). Increasing male:female ratio in the BRAFv600e+ group was associated with a lower reported recurrence, suggesting a higher recurrence rate in females. The odds of having mandibular lesion were four times higher in BRAFv600e+ cases compared to BRAFv600e- cases (confidence interval: 2.121-7.870, p < 0.001, I2  = 28.37%).

CONCLUSION

Within the BRAFv600e+ group, females showed a higher reported recurrence rate. This specific clinical group may benefit from BRAFv600e mutation investigation and potential upscaled surgical treatment and additional BRAF inhibitor therapy, which needs validation in future studies.

Clinicoradiopathologic Analysis of Odontomas: A Retrospective Study of 242 Cases

Odontomas are considered hamartomatous lesions and are one of the two most common odontogenic tumors of the jaw. Odontomas are classified as compound or complex. Recently, ameloblastic fibro-odontoma (AFO) and ameloblastic fibro-dentinoma were reclassified as developing odontomas. Though clinically odontomas are usually asymptomatic, they have adverse effects on adjacent teeth such as tooth impaction, delayed eruption, displacement of teeth, over-retention of teeth, and can give rise to odontogenic cysts within the jaw. We sought to evaluate the clinicoradiopathologic presentations of odontomas by collecting and analyzing the clinical, radiographic, and pathologic data of odontomas diagnosed in our institution from 2013 to 2022. Over this 10-year period, there were 242 patients with a histopathological and/or radiographic diagnosis of odontoma. There was no gender predilection and ages ranged from 3 to 101 years (median, 14 years). The second decade of life was the most prevalent (57.4%). There was no jaw predilection; however, the anterior jaw was the most common location. Ninety-four (38.8%) cases presented with clinical findings. The most common finding was tooth impaction (n = 83). Nine (3.7%) cases were histopathologically confirmed to be associated with other lesions such as dentigerous cysts (n = 8) and nasopalatine duct cyst (n = 1). The median age (25 years) of patients diagnosed with odontomas associated with cysts was older than patients with odontomas (14 years) without associated cysts. Compound odontomas were the most common type of odontoma compared to complex and AFOs with 71.4%, 26.6%, and 2%, respectively. The majority of compound odontomas involved the anterior jaw (69.3%) and mandible (54.9%) while the majority of complex odontomas involved the posterior jaw (59.6%) and maxilla (54.7%). The four AFOs were in the posterior jaw and 75% involved the maxilla. The median age (12 years) of patients diagnosed with AFO was the youngest compared to patients diagnosed with compound (13 years) and complex (16 years). In conclusion, we analyzed the clinical, radiographic, and pathologic features of 242 new cases of odontomas. Our study reaffirms that odontomas frequently affect the pediatric population and can disrupt their dentition. Based on the result of this study, our clinical recommendation to prevent problems to adjacent teeth from odontomas is for dentists to be apt in the diagnose of odontomas to ensure that they are surgically removed in a timely manner.

Ameloblastic fibro-dentinoma: a rare mixed odontogenic tumor case report with review of literature

BACKGROUND

Ameloblastic fibro-dentinoma is considered a rare, benign, mixed odontogenic tumor that occurs mainly in the posterior mandible in the 1st-2nd decade of life. Although the clinical behavior of Ameloblastic fibro-dentinoma is similar to that of ameloblastic fibroma, there is a debate about whether Ameloblastic fibro-dentinoma is a developing hamartomatous odontoma or a separate neoplastic odontogenic tumor like ameloblastic fibroma. However, it is important to understand the histopathogenesis of this rare tumor.

CASE PRESENTATION

A case report presenting an 11-year-old male child with a swelling in the posterior mandible. Radiographic examination revealed a multilocular lesion with mixed radiodensity related to the impacted lower left second premolar tooth. Incisional biopsy was done, and microscopic examination revealed cords and nests of odontogenic follicles lined by ameloblast-like cells and central stellate reticulum-like cells in the primitive ecto-mesenchymal stroma with areas of dentinoid material and osteodentin. The diagnosis was ameloblastic fibro-dentinoma. Surgical excision of the lesion was done, and the patient was followed up for 1 year without evidence of recurrence.

CONCLUSION

Reporting such a rare entity clarifies the debate about its nature and the importance of early diagnosis of lesions that are associated with unerupted teeth showing how it is effective in early management and prognosis.

Current concepts in targeted therapies for benign tumors of the jaw - A review of the literature

The aim of our study was to review current concepts in targeted therapies for benign tumors of the jaw. Benign odontogenic and maxillofacial bone tumors often require radical surgery, with consequent morbidity that impacts patients' postsurgical quality of life. Currently, targeted therapies and novel nonsurgical therapeutics are being explored for management of non-resectable tumors, with the aim of avoiding surgery or minimizing surgical scope. However, data on clinical applications of targeted therapies for benign tumors of the jaw remain sparse. Therefore, a literature review was conducted, based on the PubMed database, which included in vivo human clinical studies describing clinical application of targeted therapy for benign tumor of the jaw. The review assessed the outcomes of BRAF and MEK inhibitors for treatment of ameloblastoma, RANKL monoclonal antibody for treatment of giant cell tumor, cherubism, aneurysmal bone cyst, and fibrous dysplasia, and tyrosine kinase inhibitor for treatment of odontogenic myxoma and cherubism. Targeted therapies decreased tumor size, slowed down tumor progression, and reduced bone pain. Surgery remains the gold standard, but targeted therapies are promising adjuvant or alternative treatment options for reducing tumor progression and morbidity of tumor surgery.

Maxillary Sinus Ameloblastoma in Turner Syndrome: A Comprehensive Case Report and Long-Term Follow-Up

This article was previously posted to the Research Square preprint server on 16 August 2023. Maxillary sinus ameloblastoma is an uncommon, locally aggressive odontogenic tumor. In this case report, we present a comprehensive long-term follow-up of maxillary sinus ameloblastoma occurring in a patient with Turner syndrome, managed through partial right maxillectomy followed by adjuvant operative bed radiotherapy.

Head and neck carcinoma in children: A clinicopathological study of 42 cases

Background/purpose

Cancer is an important part of the global burden of childhood diseases. Head and neck carcinoma in children is rare and related research is limited. This study aimed to investigate the clinicopathological features of childhood head and neck carcinoma.

Materials and methods

Forty-two cases of childhood head and neck carcinoma treated in our institution were reviewed and analyzed.

Results

Median age overall was 11 years. Twenty-three patients (54.8%) were male and 19 (45.2%) were female. Parotid gland location was most common (54.8%). Mucoepidermoid carcinoma and squamous cell carcinoma were the most common histological types (57.1% and 11.9%, respectively). Two patients had a history of bone marrow transplantation and two had a history of odontogenic keratocyst. The recurrence rate after treatment was 8.6%.

Conclusion

Early diagnosis and treatment and close follow-up of childhood head and neck carcinoma are warranted to prevent recurrence and improve clinical outcome.

Molecular and Clinical Spectrum of Primary Hyperparathyroidism

Recent data suggest an increase in the overall incidence of parathyroid disorders, with primary hyperparathyroidism (PHPT) being the most prevalent parathyroid disorder. PHPT is associated with morbidities (fractures, kidney stones, chronic kidney disease) and increased risk of death. The symptoms of PHPT can be nonspecific, potentially delaying the diagnosis. Approximately 15% of patients with PHPT have an underlying heritable form of PHPT that may be associated with extraparathyroidal manifestations, requiring active surveillance for these manifestations as seen in multiple endocrine neoplasia type 1 and 2A. Genetic testing for heritable forms should be offered to patients with multiglandular disease, recurrent PHPT, young onset PHPT (age ≤40 years), and those with a family history of parathyroid tumors. However, the underlying genetic cause for the majority of patients with heritable forms of PHPT remains unknown. Distinction between sporadic and heritable forms of PHPT is useful in surgical planning for parathyroidectomy and has implications for the family. The genes currently known to be associated with heritable forms of PHPT account for approximately half of sporadic parathyroid tumors. But the genetic cause in approximately half of the sporadic parathyroid tumors remains unknown. Furthermore, there is no systemic therapy for parathyroid carcinoma, a rare but potentially fatal cause of PHPT. Improved understanding of the molecular characteristics of parathyroid tumors will allow us to identify biomarkers for diagnosis and novel targets for therapy.

Ameloblastic Fibro-Odontoma of the Posterior Mandible: A Rare Pathological Entity

Ameloblastic fibro-odontoma (AFO) is a rare, slow-growing neoplastic lesion classified as a benign, epithelial mixed odontogenic tumor with odontogenic mesenchyme. This tumor demonstrates the histological features characteristic of both ameloblastic fibromas and complex odontomas. The clinical manifestation of AFO is typically characterized by asymptomatic enlargement of the jawbones. Radiographically, it presents as a distinct radiolucent region, indicating the presence of radiopaque substances with varying degrees of irregularities in size and morphology. Standard therapeutic intervention involves enucleation. Despite its benign nature, AFO can cause significant morbidity if left untreated. Therefore, prompt diagnosis and appropriate management are essential to ensure optimal patient outcomes. The following case report details the clinical presentation and management of an 18-year-old male with an AFO lesion located in the posterior mandible. This particular case was treated with conservative measures involving surgical enucleation.

Odontogenic Carcinosarcoma: An Updated Literature Review and Report of a Case

BACKGROUND

Odontogenic carcinosarcoma (OCS) is an exceptionally rare malignant mixed odontogenic neoplasm, which mostly arises from recurrent benign odontogenic tumour that undergoes malignant transformation.

METHODS

A literature review was conducted using the keyword of "Odontogenic carcinosarcoma" and all relevant articles were screened. The data collected include demographic profile (age, gender), clinical information (symptoms, location, size), radiologic features, histopathological examination, management, recurrence, metastases, and survival status.

RESULTS

A total of 17 OCS cases including a new case from our hospital. The incidence of OCS was highest in the third decades of life with predilection for male and posterior region of mandible. Clinically, patients may present with swelling and neurological symptoms. Radiographic examination often showed radiolucency with ill-defined border. This tumour demonstrates an aggressive behaviour with reported cases of distant metastases to the lung, lymph nodes, rib, and pelvis. Here, we report an interesting case of OCS in a 38-year-old man with a previous diagnosis of ameloblastoma. The patient was diagnosed with ameloblastoma but refused surgical intervention and returned after 10 years with rapidly enlarging mass on the right side of mandible. Microscopically, the lesion appears as biphasic odontogenic tumour with malignant cytological features seen in both epithelium and mesenchymal components. The spindle to round mesenchymal tumour cells were only positive for vimentin. Ki67 proliferation index was high in both epithelium and mesenchymal components.

CONCLUSION

This case showed the tendency of untreated ameloblastoma to undergo malignant changes in the long term.

Metastasising ameloblastoma or ameloblastic carcinoma? A case report with mutation analyses

BACKGROUND

Ameloblastic carcinoma and metastasising ameloblastoma are rare epithelial odontogenic tumours with aggressive features. Distinguishing between these two lesions is often clinically difficult but necessary to predict tumour behaviour or to plan future therapy. Here, we provide a brief review of the literature available on these two types of lesions and present a new case report of a young man with an ameloblastoma displaying metastatic features. We also use this case to illustrate the similarities and differences between these two types of tumours and the difficulties of their differential diagnosis.

CASE PRESENTATION

Our histopathological analyses uncovered a metastasising tumour with features of ameloblastic carcinoma, which developed from the ameloblastoma. We profiled the gene expression of Wnt pathway members in ameloblastoma sample of this patient, because multiple molecules of this pathway are involved in the establishing of cell polarity, cell migration or for epithelial-mesenchymal transition during tumour metastasis to evaluate features of tumor behaviour. Indeed, we found upregulation of several cell migration-related genes in our patient. Moreover, we uncovered somatic mutation BRAF p.V600E with known pathological role in cancerogenesis and germline heterozygous FANCA p.S858R mutation, whose interpretation in this context has not been discussed yet.

CONCLUSIONS

In conclusion, we have uncovered a unique case of ameloblastic carcinoma associated with an alteration of Wnt signalling and the presence of BRAF mutation. Development of harmful state of our patient might be also supported by the germline mutation in one FANCA allele, however this has to be confirmed by further analyses.

Novel Three-Dimensional and Non-Invasive Diagnostic Approach for Distinction between Odontogenic Keratocysts and Ameloblastomas

Aim of this study was to demonstrate the diagnostic ability to differentiate odontogenic keratocysts (OKCs) from ameloblastomas (AMs) based on computed tomography (CT) or cone beam computed tomography (CBCT) scans. Preoperative CT and CBCT scans from 2004 to 2019 of OKCs and AMs were analyzed in 51 participants. Lesions were three-dimensionally (3D) assessed and Hounsfield units (HU) as well as gray scale values (GSV) were quantified. Calculated HU spectra were compared within the same imaging modalities using unpaired t-tests and correlated with participants characteristics by calculating Pearsons correlation coefficients. Within the CT scans, AMs had highly significantly higher HU values compared to OKCs (43.52 HU and 19.79 HU, respectively; p < 0.0001). Analogous, within the CBCT scans, AMs had significantly higher GSV compared to OKCs (-413.76 HU and -564.76 HU, respectively; p = 0.0376). These findings were independent from participants' gender and age, anatomical site, and lesion size, indicating that the HU- and GSV-based difference reflects an individual configuration of the lesion. HU and GSV spectra calculated from CT and CBCT scans can be used to discriminate between OKCs and AMs. This diagnostic approach represents a faster and non-invasive option for preoperative diagnosis of such entities and has potential to facilitate therapeutic decision making.

Mixed-Pattern Ameloblastoma of the Anterior Mandible: A Rare Histopathological Presentation at an Infrequent Location

Ameloblastoma is a benign odontogenic tumor of epithelial origin that exhibits a locally aggressive behavior with a high level of recurrence and multiple factors involved in its molecular pathogenesis. This article is a case report of a 46-year-old male patient suffering from a progressively enlarging tumor of the anterior mandible that caused gradual expansion of the lingual cortical plate and root displacement without resorption of the involved teeth. Incisional biopsy was consistent with "conventional" ameloblastoma, showing a mixed pattern of both the follicular and acanthomatous subtypes. This diagnosis was corroborated through a histopathological examination of the resected specimen. The patient was submitted to en bloc resection (marginal mandibulectomy) with preservation of the lower mandibular border; dental rehabilitation was achieved through a removable prosthesis. He remains disease-free for 5.5 years postoperatively and is highly satisfied with mastication and speech. The objective of this report is to highlight a relatively rare histopathological presentation of the "conventional" ameloblastoma, involving a site not commonly affected by ameloblastomas, the anterior mandible and crossing the midline, in a relatively young male patient.

Management of Permanent Teeth in Dentigerous Cysts in Children: A Case Report

Dentigerous cysts are the second most common odontogenic lesion, after radicular cysts. Dentigerous cysts mainly affect individuals in their second to fourth decades of life, with a slight male predominance. Because diagnosis is often late, surgical procedures like enucleation and removal of the impacted tooth misplaced are often necessary. However, if a dentigerous cyst is detected early in a child with delayed tooth eruption, the treatment goal is to preserve and properly position the permanent tooth within the arch. In such cases, conservative approaches like cyst decompression may be considered appropriate. We present a case of a dentigerous cyst in a 10-year-old child with delayed eruption of teeth 22 and 23. The condition was managed using decompression alone and orthosurgical traction, which facilitated the proper placement of the impacted teeth within the arch. This article emphasizes the significance of a multidisciplinary approach involving surgical and orthodontic management for dentigerous cysts in children, along with the importance of patient compliance with the treatment plan.

A network meta-analysis assessing the effectiveness of various radical and conservative surgical approaches regarding recurrence in treating solid/multicystic ameloblastomas

Multiple treatment approaches have been undertaken to reduce the incidence of recurrence in solid/multicystic ameloblastoma (SMA), both conservative and radical. A network meta-analysis (NMA) was conducted to assess and compare the effectiveness of these various treatment approaches concurrently. This study was reported based on the Preferred Reporting Items for Systematic Reviews for Network Meta-Analysis (PRISMA-NMA) statement. PubMed (MEDLINE), ScienceDirect, Scopus, and Web of Science were searched until August 10, 2021. The NMA was conducted using the STATA program. Of 1153 records identified in the search, seven observational studies with 180 patients were included. Six different treatment approaches were identified. Segmental resection ranked highest for reducing the recurrence rate with the highest SUCRA score (77.7), followed by curettage with cryotherapy (66.9) and marginal resection (49.3). Network inconsistencies and publication bias appeared to be absent. According to the Confidence in Network Meta-Analysis (CINeMa) method, the evidence's certainty was low for all comparisons due to imprecision and within-study bias. In conclusion, this study is the first NMA in the field of ameloblastoma. Segmental resection seemed to be the most effective treatment approach for minimizing recurrence in SMA patients. Nevertheless, weak certainty of evidence makes that the results must be regarded with caution.

Partial response to niraparib in combination with tislelizumab in a patient with metastatic undifferentiated tonsillar carcinoma: a case report and literature review

Undifferentiated tonsillar carcinoma is an extremely rare head and neck cancer. The treatment options are challenging due to insensitivity to chemotherapy and easy development of drug resistance. In this study, we reported a case of advanced undifferentiated tonsillar carcinoma with multiple mediastinal lymph node metastases that failed to respond to chemotherapy. Next-generation sequencing (NGS) revealed germline BReast CAncer gene (BRCA) 1 mutation and a high tumor mutational burden. Poly (adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors have demonstrated efficacy in solid tumors with BRCA1/2 mutations. Immune checkpoint inhibitors (ICIs) provide a treatment option for unresectable head and neck cancer. After local control treatment by embolization, niraparib and tislelizumab were administered to this patient. A partial response (PR) was achieved, and progression-free survival (PFS) and overall survival (OS) were 12 months and 19 months, respectively. This case reveals molecular profiling as an important therapeutic strategy for rare malignancies with no standard of care. Moreover, the underlying synergistic antitumor activity of PARPi and PD-L1 blockade was reviewed.

Ameloblastoma of the Mandible With Carcinoma Transformation in a Young Adult

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.

Huge complex composite odontoma of mandible

A young female patient reported to the department of oral and maxillofacial surgery with complaint of asymptomatic swelling in left posterior region of lower jaw since 6 months. Complete intraoral and extraoral clinical examination was done. Routine radiographical investigations were advised. Based on clinical and radiographical findings she was provisionally diagnosed with odontoma of left mandible. It was a considerably giant mass with thinned out both cortical plates and the inferior border of the mandible. Although we assumed high risk of fracture of the mandible, successful surgical excision of the tumour was done using a minimally invasive intraoral approach and by sectioning the odontoma, sparing cortical bones. We managed to remove the whole of tumour without fracturing the mandible. Final histopathological report confirmed the initial diagnosis of complex composite odontoma. Patient is under regular follow-up.

Potential involvement of polycystins in the pathogenesis of ameloblastomas: Analysis based on bioinformatics and immunohistochemistry

OBJECTIVE

To perform an integrated analysis in identifying novel hub genes that could facilitate the diagnosis and targeted therapy of ameloblastoma.

DESIGN

The expression profiling dataset, GSE38494, was obtained from the Gene Expression Omnibus database. Differentially expressed genes were identified through GEO2R online tool and characterised via Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The protein-protein interaction network and hub genes were screened using the STRING database and Cytoscape software. Subsequently, an upregulated gene was selected for further validation using the GSE132472 dataset. Further, immunohistochemistry was performed to assess the expression of the selected gene in ameloblastomas, odontogenic keratocysts, dentigerous cysts, and gingival tissues. The diagnostic and therapeutic utility of the selected hub genes were further verified by receiver operating characteristic analysis and the DGIdb database.

RESULTS

We identified six hub genes in ameloblastoma, among which the upregulated gene PKD2 and its related gene PKD1 were further validated. GO functional annotation revealed that PKD2 is involved in cell-cell junction, extracellular exosome, cytoplasm, endoplasmic reticulum, and calcium ion transport. The immunohistochemical analysis showed that the expression of polycystin-1 and polycystin-2, encoded by the PKD1 and PKD2 genes, respectively, was upregulated in ameloblastoma. PKD1 and PKD2 had a high diagnostic utility for ameloblastoma, and allopurinol interacted with the PKD2 gene.

CONCLUSION

Our research indicates that polycystins are highly expressed in ameloblastoma and might be involved in the oncogenesis of ameloblastoma, thus offering a new perspective on the molecular mechanisms and targeted therapies on ameloblastoma.

Ameloblastoma of the jaws in adult: A retrospective review of local recurrent lesions based on the resection margin in the adjacent apparent healthy tissues

Background

The surgical treatment of ameloblastoma of the jaws remains contentious due to the variable recurrence rate amongst its variants, the tumor's local invasive behavior, and the lack of consensus among surgeons concerning the extent of resection in the contiguous healthy tissues.

Objective

To determine the recurrence rate of ameloblastoma and its association with the resection margins.

Materials and methods

This is a retrospective cohort study of the medical records of patients who underwent surgical resection of the jaws as the primary modality of treatment for ameloblastoma. Clinical data over the 26 years were analyzed for age, gender, site of the lesion, size, radiographic appearance, histopathological sub-type, and the incidence of recurrence post-treatment. Descriptive and bivariate statistics were computed.

Results

A retrospective audit of 234 cases was included in the study that was typical (solid/multicystic) ameloblastoma. The age of patients ranged from 20 to 66 years with a mean age of 33.4 ± 9.6 years, and a male-to-female ratio of 1.2: 1 (P = 0.52). The follicular and plexiform types accounted for the majority of histopathological variants (89.8%; P = 0.000). Overall, 6.8% of cases relapsed after the initial primary surgery. The rate of recurrence was high with a resection margin of 1.0 or 1.5 cm than 2.0 cm (P = 0.001). No case of recurrence was seen with a resection margin of 2.5 cm margin.

Conclusion

A low recurrence rate of 6.8% was noted in our series of cases. A wide 2.5 cm resection margin is recommended in the adjacent healthy tissues.