Exceptional Evolution of a Squamous Odontogenic Tumor in the Jaw: Molecular Approach.

A squamous odontogenic tumor (SOT) is an epithelial locally benign neoplasia derived from the periodontium of the jaws. It is considered a lesion of low incidence. Predominantly, it affects the mandible, although both jaw bones may be involved. Here, we discuss the malignant clinical evolution of an SOT lesion in an 80-year-old female patient. The patient exhibited an expansive triangular lesion at the inferior right quadrant. Surgery was performed and an SOT was diagnosed (2019). Two years after, the lesion grew, and the analysis of the biopsy revealed SOT malignization with pleomorphic atypical squamous cells, characteristics of a squamous cell carcinoma (2021). Massive DNA sequencing of formalin-fixed-paraffin-embedded specimens of the initial and relapsed tumors indicated pathogenic mutations in RET and POLE genes in both tumors, loss of ALK, and gain of CDKN1B and MAP2K in the relapse. In addition, the clinical, radiographic, and microscopic features of this neoplasm are discussed and compared with those already published. The case presented contributes to the better understanding of this SOT tumor entity and to indicates its malignant evolution, together with its biological behavior and its histologic, clinical, and radiographic features. Also, it aims to stress the importance of deeper genetic analyses in rare diseases to uncover mutations that help to select a personalized treatment.

Surgical Management of an Aggressive Multifocal Squamous Odontogenic Tumor.

Squamous odontogenic tumor is a rare benign epithelial odontogenic tumor of the jaw. Most are solitary lesions, although rare multifocal lesions have been described. Maxillary lesions have more aggressive behavior. Because of their benign character, these lesions are usually treated using a conservative surgical approach with curettage and surgical enucleation. This report describes the case of a 29-year-old woman with multifocal lesions who was initially treated with conservative surgical therapy. Early recurrence 6 months after surgery prompted more aggressive resection. This case is discussed in the context of current evidence related to the epidemiology, etiology, diagnosis, and therapy of squamous odontogenic tumors.

Review of 109 cases of primary malignant orofacial lesions seen at a Nigerian Tertiary Hospital.

BACKGROUND: Orofacial malignancy is a growing health issue common in developing regions of the world. Presentation patterns are myriad with geographic variations. Advanced stage owing to late presentation constitutes a significant public health burden. The site and type of the lesions are valuable in diagnosis and patient management. AIM: This study aims to review cases of primary orofacial malignancies at the OAUTHC Dental Hospital. OBJECTIVES: The objective of the study was to determine the prevalence of histologically diagnosed orofacial malignancies, the relative frequencies, types and site of distribution. MATERIALS AND METHODS: Records of patients with orofacial malignancies at the OAUTHC, Dental Hospital over a period of 10 years (January 2008-December 2017) were reviewed, demographic data (age, gender and site), history of tobacco use were retrieved and entered into a pro forma. The data obtained were analysed with STATA 11. Statistical significance was set at P < 0.05. RESULTS: Of 375, 109 cases of neoplasms seen were primary malignant tumours, with prevalence rate of 29.1%. There were 71 (65.1%) males and 38 (34.9%) females (male:female ratio of 1.87:1), mean age (48.7 ± 19.3 years) and range (4-94 years). Affected sites were mandible (41, 37.6%), maxilla (39, 35.8%), palate (17, 15.6%) and others. Lesions were mainly squamous cell carcinomas (SCC: 46, 42.2%), salivary gland adenocarcinomas (SGAs, 25, 22.9%) including 8 (32%) cases of adenoid cystic carcinoma (ACC). Others were odontogenic carcinoma (18, 16.5%) and lymphoma (8, 7.3%). Most specimen analysed were hard tissues (n = 63, 57.8%). Thirty-four (73.9%) cases of SCC and 66 (60.6%) cases of primary malignancies were in the 5th-9th decades of life. This was statistically significant at P = 0.000. CONCLUSION: SCC was more prevalent than salivary and odontogenic carcinomas. ACC and mucoepidermoid carcinoma were two most common SGAs. Metastatic tumours to the jaws are rare.

Metallothionein immunoexpression in selected benign epithelial odontogenic tumors.

BACKGROUND: Odontogenic tumors exhibited variable biologica behaviors. Metallothionein (MT) is correlated with the cellular homeostasis of essential metals, cellular differentiation, and proliferation. The core goals of this study are (i) to report and to compare MT expression among benign epithelial odontogenic tumors; (ii) to correlate MT with cellular proliferation index; and (iii) to evaluate the influence of the inflammatory infiltrate on MT expression. MATERIALS AND METHODS: Ten cases of solid ameloblastomas (SABs), 4 squamous odontogenic tumors (SOTs), 5 adenomatoid odontogenic tumors (AOTs), and 3 calcifying epithelial odontogenic tumors (CEOTs) were subjected to immunohistochemical to anti-MT, anti-Ki-67, and anti-PCNA. Statistical analysis was performed using BioEstat(®) 4.0. RESULTS: Metallothionein staining was found to be the highest in the SABs (93.1%), followed by SOTs (52.9%), AOTs (38.4%), and CEOTs (0%). MT staining exhibited statistically significant differences between the SABs and the SOTs (P = 0.0047) and the AOTs (P = 0.0022). A weak-to-strong positive correlation between IMT and IK or IP was observed in SABs and SOTs, whereas a strong negative correlation was observed in AOTs. No differences in IMT, IK, and IP were observed between inflammation groups A and B. CONCLUSIONS: The increased MT expression observed in the SABs might be correlated with clinical behavior (local invasiveness and high rate of recurrence). In the SABs and SOTs, MT plays a role in the stimulation of cellular proliferation. In contrast, MT can inhibit cellular proliferation in the AOT. The IMT, IK, and IP are not affected by inflammation.

Squamous Odontogenic Tumor in the Posterior Region of Maxilla.

Squamous odontogenic tumor (SOT) is a rare benign but locally infiltrative tumor often misdiagnosed as other entities, such as ameloblastoma and squamous cell carcinoma, due to overlapping morphological findings. We document here the clinicopathological and imaging findings of an aggressive intraosseous SOT in the posterior left region of the maxilla in a 25-year-old male patient. On intraoral examination, the tumor extended from the region of the left lateral incisor to the upper left premolar and was covered by reddish mucosa, with discrete areas of ulceration. Imaging exams revealed an osteolytic lesion causing thinning, erosion, and buccal and lingual cortical plate perforation associated with an impacted canine. Microscopically, the tumor showed a proliferation of islands of well-differentiated squamous epithelium in a variably collagenized background. The peripheral cells of the islands were flat or slightly cuboidal and did not exhibit nuclei with peripheral palisade and reverse polarization. The diagnosis of SOT was rendered. The patient underwent surgical resection and has been under clinical follow-up for approximately 12 months with no signs of recurrence. A careful morphological evaluation is essential to avoid misdiagnosis and ensure a satisfactory treatment approach.

A clinicopathological study of malignant odontogenic tumours.

AIMS: Malignant odontogenic tumours (MOTs) are rare neoplasms occurring primarily within the jaw. The objective of this study was to determine the incidence, demographics and clinicopathological features of the MOTs from two institutions. METHODS AND RESULTS: The records of the Department of Oral Pathology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand and the Department of Oncology and Diagnostic Sciences, Dental School, University of Maryland, Baltimore, USA were searched from 1991 to 2010; we identified 17 cases of previously diagnosed MOTs. All cases were reviewed independently of the previous diagnosis by two blinded oral pathologists and reclassified based on the 2005 World Health Organization classification of head and neck tumours. In this study we describe in detail these 17 cases which presented with an average age of 50.29 years and a male to female ratio of 2.4:1. These cases included five ameloblastic carcinomas, four atypical ameloblastomas, three primary intraosseous squamous cell carcinomas, three intraosseous mucoepidermoid carcinomas and two clear cell odontogenic carcinomas. All cases were treated by surgical resection and one patient with ameloblastic carcinoma received postoperative radiotherapy. CONCLUSIONS: Malignant odontogenic tumours are considered rare central odontogenic lesions. Awareness of their existence, rapid diagnosis and successful treatment using surgery, radiation and/or chemotherapy is critical to patient survival.

[Therapy-resistant aggressive cystic lesion of the mandible]. / Therapieresistente aggressive zystische Läsion des Unterkiefers.

Several extensive surgical interventions of a cystic lesion in the left mandible were followed by recurrences. The lesion extended from the primary mandibular region into the area of pterygopalatine fossa finally infiltrating the orbital region and the skull base. Histological results could never demonstrate a malignancy with certainty. Due to the patient's poor general condition, the refusal for further surgical inventions and due to the malignoma-like growth pattern radiation treatment was performed. However, this had no effect on tumor progression.

Squamous odontogenic tumor of the mandible: a case report demonstrating immunoexpression of Notch1, 3, 4, Jagged1 and Delta1.

BACKGROUND: Squamous odontogenic tumor (SOT) is a rare benign odontogenic epithelial neoplasm. A slow-growing painless expansive swelling is the common presenting symptom. Histopathologically, SOT can be easily misdiagnosed as an acanthomatous ameloblastoma. Although Notch receptors and ligands have been shown to play a role in cell fate decisions in ameloblastomas, the role of these cell signaling molecules in SOT is unknown. CASE REPORT: This paper describes a case of SOT affecting the anterior mandible of a 10-year-old Indian female. The patient was treated by local surgical excision and there has been no follow-up clinical record of recurrence 5 years after primary treatment. Histo?pathological examination revealed a solid, locally-infiltrative neoplasm composed of bland-looking squamatoid islands scattered in a mature fibrous connective tissue stroma and the diagnosis was SOT. Immunohistochemical evaluation showed positive reactivity of varying intensity in the neoplastic epithelial cells for Notch1, Notch3, Notch4, and their ligands Jagged1 and Delta1. Expression patterns showed considerable overlap. No immunoreactivity was detected for Notch2 and Jagged2. CONCLUSIONS: Present findings suggest that Notch receptors and their ligands play differential roles in the cytodifferentiation of SOT.

Comparative expression of calretinin in selected odontogenic tumours: a possible relationship to histogenesis.

AIMS: Calretinin, a calcium-binding protein, is expressed primarily in certain subtypes of neurons. It has also been reported to be present in mesotheliomas and other tumours. The aim was to determine the expression of calretinin in selected odontogenic neoplasms. METHODS AND RESULTS: Immunohistochemistry for calretinin was performed on 55 odontogenic tumours consisting of 20 solid ameloblastomas, five calcifying epithelial odontogenic tumours, 10 adenomatoid odontogenic tumours, 10 ameloblastic fibromas and 10 odontogenic myxomas. The distribution, intensity, pattern and localization of immunoreactive cells were determined by conventional light microscopy. chi(2) test was used for statistical analysis and P < 0.05 was considered to be significant. All 20 ameloblastomas showed intense immunopositivity with a diffuse distribution pattern. None of the other neoplasms was reactive with calretinin. Differences in the proportion of calretinin expression between groups were statistically significant at P < 0.001. CONCLUSIONS: Considering that ameloblastomas, in contrast to the other studied tumours, were consistently reactive for calretinin, this protein may have a role in the pathogenesis of this aggressive neoplasm.

[Benign epithelial odontogenic tumors]. / Benigne epitheliale odontogene Tumoren.

The group of benign epithelial odontogenic tumors consists of the four member types of the ameloblastoma family (solid/multicystic, extraosseous/peripheral, desmoplastic, unicystic), squamous odontogenic tumors, calcifying odontogenic tumors, adenomatoid odontogenic tumors, and keratocystic odontogenic tumors, the former "keratocysts" that were recently reclassified by the World Health Organization and are now regarded as tumors. The latter are by far the most frequent tumors in this group, followed by solid/multicystic ameloblastoma. Although the etiology of these lesions is still unknown, a close relationship to normal tooth development is obvious, which is partially imitated by some tumors. Despite some similarities to each other, at least in part, the biological behavior of these lesions is quite different, as are treatment modalities. The diagnosis is essentially based on localization (intraosseous vs. extraosseous/peripheral) and histology, whereupon the correlation of histological findings with radiographic morphology may be of additional diagnostic value. Because of the range of variation, immunohistochemical investigations are not helpful in diagnosing a particular case.

Glandular odontogenic cyst of the mandible: from incidental radiographic discovery to prosthetic reconstruction.

A large multilocular radiolucent lesion involving the anterior mandible was noted incidentally in a 44-year-old woman who sought routine dental treatment. An incisional biopsy revealed that this lesion represented an uncommon developmental odontogenic cyst known as a glandular odontogenic cyst. The lesion was removed surgically, followed by reconstruction with a right anterior iliac crest bone graft. This article reviews the radiographic, clinical, and histopathologic appearance of this rare odontogenic cyst, as well as the surgical management and the patient's subsequent prosthetic rehabilitation.

Squamous odontogenic tumor and squamous odontogenic tumor-like proliferations in odontogenic cysts: An updated analysis of 170 cases reported in the literature.

PURPOSE: To integrate the available data published on squamous odontogenic tumors (SOT) and squamous odontogenic tumor-like proliferations in odontogenic cysts (SOT-LPOC) into a comprehensive analysis of their clinical/radiologic features. MATERIALS AND METHODS: An electronic search was undertaken in January 2017. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm a definite diagnosis. RESULTS: A total of 74 publications reporting 110 SOTs (102 central, 8 peripheral) and 60 SOT-LPOC were included. Compared to SOT-LPOC, SOT showed lower mean age, no preference regarding maxilla or mandible localization, significant association with cortical bone perforation, multilocular radiographic appearance, and mobility of the tooth/teeth associated with the lesion. While 5 recurrent SOT were reported after enucleation, no recurrent SOT-LPOC was found. CONCLUSIONS: SOT shows a more aggressive biologic behavior than SOT-LPOC, which supports the hypothesis that the two lesions are distinct clinicopathological conditions.

A squamous odontogenic tumor following an orthodontic micro-screw: A rare case report and review of the literature.

We reported a very rare case of squamous odontogenic tumor(SOT) in a 23-year-old female. The tumor arose after an implanting operation of an orthodontic micro-screw, and was definitely diagnosed by the histopathological examination. Based on the case report and a review of the literature, we discussed about the general features, differential diagnosis and pathogenesis of SOT.

Localized gingival enlargement associated with alveolar process expansion: peripheral ossifying fibroma coincident with central odontogenic fibroma.

BACKGROUND: Despite the common occurrence of localized gingival enlargements, which often represent reactive lesions, the temporal and spatial association of such a lesion with a central jaw lesion has not been reported. The purpose of this case report is to present the exceptional combination of a peripheral ossifying fibroma and a central odontogenic fibroma. The differential diagnosis and management of each lesion is reviewed. METHODS: A 45-year-old black female presented with a chief complaint of a painless protuberance in the left mandible of 1-year duration. Clinical and radiographic examination revealed a gingival enlargement localized between teeth #21 and #23 and a multilocular radiolucent lesion with radiopaque foci in the same area. Excisional biopsy of the gingival lesion and incisional biopsy of the central lesion were performed, and specimens were submitted for histopathological analysis. RESULTS: Biopsy of the gingival lesion revealed stratified squamous epithelium and highly cellular fibroblastic component presenting central areas of calcification, features consistent with a diagnosis of peripheral ossifying fibroma. The central lesion was characterized by cellular fibrous tissue admixed with rests of odontogenic epithelium and few calcification areas, features consistent with a diagnosis of central odontogenic fibroma/World Health Organization type. Subsequently, the central lesion was enucleated. After 1-year follow-up, no recurrence has been observed. CONCLUSIONS: The combination of a rare central lesion with a common gingival lesion may present unique diagnostic and therapeutic challenges. Clinician awareness regarding the possibility of such a combined presentation and its implications will help to ensure optimal treatment outcomes.

Aggressive maxillary squamous odontogenic tumour in a child: histological dilemma and adaptative surgical behaviour.

A case of a maxillary osteolytic tumour is described in a 9-year-old boy. Histological analysis led to an initial diagnosis of benign squamous odontogenic tumour, although this was not straightforward due to swelling, and cellular pseudo-malignant and non-specific signs. Because of the young age of the patient, a local surgical tumourectomy was first chosen with respect to the mixed dentition. For 10 months, the evolution was satisfactory. Then, a very aggressive tumoural recurrence with lip and palate infiltration led to doubts as to the histologic nature of the tumour. Efficient collaboration between several specialized pathologist teams finally confirmed that this was a squamous odontogenic tumour but in a very aggressive form. Radical surgery was then carried out.

Multicentric Squamous Odontogenic Tumor: A Case Report and Review of the Literature.

Squamous odontogenic tumor (SOT) is a rare benign epithelial odontogenic neoplasm of the jaws. Both intraosseous and peripheral SOTs have been described in the English language literature. While most intraosseous SOTs occur as solitary lesions, a multicentric variant has also been previously described. Although the radiographic and microscopic features are identical for both solitary and multicentric clinical presentations, there are three significant differences between them. More specifically, multicentric SOT presents at an earlier age (third decade of life), has a slightly higher male to female ratio than the solitary type and has a marked predilection for African-Americans. Here we document the eighth reported case of multicentric SOT, which was diagnosed in a 43-year-old African-American male. In addition, we feature focal sebaceous metaplasia, a heretofore unknown microscopic feature of SOT. Clinical, radiological, and histopathological findings are discussed. The differential diagnosis, biological behavior and management modalities for SOT are also addressed.

Clear cell odontogenic carcinoma, diagnostic difficulties. A case report.

INTRODUCTION: Clear cell odontogenic carcinoma (COCC) is a rare tumor described by Hansen et al. in 1985. The clinical and radiological manifestations are multiple and the diagnosis is histological. OBSERVATION: A 64-year-old patient consulted us for a right mandibular osteolytic lesion associated to a homolateral labial hypoesthesia. A biopsy was performed under local anesthesia. Histology was consistent with a metastatic lesion of clear kidney cell carcinoma, COCC, or odontogenic squamous tumor. Additional tests eliminated a metastatic lesion. A wide excision of the lesion by hemi-mandibulectomy associated with lymph node dissection and reconstruction by a fibula osteoseptocutaneous flap was performed. Presence of a fission of the EWSR1 gene on the histological examination of the surgical specimen made the diagnosis of COCC. DISCUSSION: Our observation illustrates the difficulty of diagnosing COCC. The new contribution of the cytogenetic techniques such as FISH-type techniques makes possible the improvement of the diagnosis.

Primary intraosseous carcinoma and odontogenic cyst. Three new cases and review of the literature.

INTRODUCTION: The Odontogenic Primary Intraosseous Carcinoma (PIOC) are a rare group of malignant tumours with strict clinic and anatomy pathological diagnosis criteria. The different classification suggested for these tumours and the small amount of cases described in literature makes it hard to know exactly how many of the cases published until now are real. MATERIAL AND METHODS: We present three new cases of PIOC originated from a previous cystic lesion that where treated in our Hospital. Two of them in the posterior jaw region where is more frequent, and the third in the upper jaw. We explain the procedure we used in each case and the aesthetic-functional reconstruction used witches are two fibula osteomyocutaneous free flaps and a bone graft of iliac crest and further placing of implants. The classification, the clinical and radiological diagnosis, the treatment and its survival are discussed. RESULTS: In all three cases we were able to see in the anatomy pathological study an epithelial, exclusively without surrounding oral mucosa affectation or tissues near the lesion as well as the lack of tumorous pathology in other parts of the body. One of the patients died because of premature massive cervical recidiva while the other two patients are currently free form illness, for ten years one of them and fifteen months the other. CONCLUSIONS: The anatomy pathological study of all of the lesions of cystic characteristics at jaw level is very important because of the risk of coexisting with carcinomatous cells. The treatment of these tumours consists in practising aggressive surgery and, in some cases, radio and/or chemotherapy post intervention.

Prognostic Factors of Primary Intraosseous Squamous Cell Carcinoma (PIOSCC): A Retrospective Review.

OBJECTIVES: To delineate clinical and pathological features and determine the prognostic factors of primary intraosseous squamous cell carcinoma (PIOSCC). MATERIALS AND METHODS: Patients diagnosed with PIOSCC, attending the department of oral and maxillofacial surgery, Nanjing stomatological hospital between 2005 and 2015, were identified and retrospectively reviewed for clinical and pathological characteristics. Therapeutic modalities were measured and related follow-up data recorded, in order to determine prognostic factors of PIOSSC. RESULTS: A total of 77 patients with PIOSCC were included in the study. Mean age at diagnosis was 58.8 years, (range, 37-81 years). Of the 77 patients, there were 58 men and 19 women. The most common location of disease was the mandible (71.42%), particularly the posterior mandible. The common presenting symptoms included jaw swelling (79.2%) and ulceration (42.65%). The estimated 2-year and 5-year overall survival were 68.9% and 38.8%, respectively. Univariate analysis identified the following as negative prognostic factors: histological grade, N classification, nodal status and treatment modalities. However, multivariate analysis determined positive nodal status, high histological grade and advanced N classification as the independent significant prognostic factors. CONCLUSION: Our results demonstrate several clinical and pathological features of PIOSCC and identify important prognostic factors associated with overall survival in PIOSCC. These prognostic factors include nodal status, histological grade, N classification, and treatment modalities, all of which are important for patient counseling and may be useful for the development of new treatment approaches.