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.

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.

Squamous Odontogenic Tumor: Review of the Literature and Report of a New Case.

PURPOSE: Squamous odontogenic tumor (SOT) is a rare, benign, locally infiltrative odontogenic tumor of the gnathic bones. It is composed of islands of bland, well-differentiated squamous epithelium of varying shape and size. Because of histologic overlap, SOT has often been overdiagnosed as ameloblastoma and squamous cell carcinoma. It thus becomes important to understand the clinical, radiologic, histopathologic, and treatment characteristics of this tumor. MATERIALS AND METHODS: Using the PubMed and Google Scholar databases, we searched for reported cases of SOT published in the English-language literature. We were able to retrieve 49 acceptable cases and perform a comprehensive literature review of the intraosseous SOTs, with emphasis on their clinical, radiographic, and pathologic characteristics, as well as treatment strategies. In addition, we present an additional case of SOT affecting the posterior mandible in a 44-year-old female patient. RESULTS: The tumor in the posterior mandible in our patient was accompanied by acute pain and treated by enucleation. Histopathologic evaluation showed variably sized islands of benign squamous epithelium scattered in a fibrous stroma, consistent with the diagnosis of an SOT. Uneventful healing was noted at the 1-month postoperative appointment. However, the patient was lost to long-term follow-up. Our literature review showed that the average age at the time of diagnosis of SOT is 34.2 years. Men and women are equally affected, and the tumor does not show a predilection for either jaw bone. The most common locations are the anterior maxilla and posterior mandible. Most SOTs are treated conservatively by enucleation or curettage, whereas aggressive or recurrent tumors require radical resection. CONCLUSIONS: Careful evaluation of the excised specimen, with immunohistochemical investigations, may prove rewarding in differentiating an SOT from other odontogenic neoplasms and thus minimize the patient's chances of undergoing an unnecessary aggressive intervention.

The first parent-child diagnosis of a multifocal squamous odontogenic tumor: A case report.

Squamous odontogenic tumors (SOT) are rare, benign, odontogenic neoplasms of the jaws. The sporadically reported cases with multifocal SOTs seem to have a marked predilection for younger African American patients. In this case report a 14-year-old Caucasian male presented with swelling of the vestibular alveolar process, slight tooth divergence, and mobility. A multifocal squamous odontogenic tumor was diagnosed and subsequently treated twice with surgical enucleation. Two and a half years earlier his mother was diagnosed and treated for a similar multifocal SOT. Next-Generation-Sequencing targeted resequencing mutational analysis of the maternal surgical specimens was performed. No potential causal mutation could be identified. Postoperative follow-up of the patient showed no recurrence of the SOT after 2 years. This case report substantiates the possibility of a familial relationship in (multifocal) SOT, possibly changing current ideas concerning the etiology and treatment of these neoplasms.

Maxillary dentigerous cyst showing squamous odontogenic tumor-like proliferation: surgical approach and literature review

Squamous odontogenic tumor (SOT) is a rare benign neoplasm of the jaw that likely arises from remnants of the dental lamina. It is a slow-growing lesion, with a radiolucent appearance in the central variant. Microscopically, SOT shows islands of squamous epithelium supported by fibrous stroma. In rare cases, squamous odontogenic tumor-like proliferation (SOT-LP) can be observed arising from odontogenic cysts (SOT-LPOC). Herein, we describe the case of a 42-year-old man who presented with discreet bleeding in the maxillary gingiva. Imaging revealed a well-defined, ovoid-shaped lesion with sclerotic margins involving tooth #18 in the intraosseous location. Fine needle aspiration supported the cystic nature of the lesion. After surgery, microscopy revealed a dentigerous cyst showing SOT-LP features. There was no recurrence after a 3-year follow-up. To the best of our knowledge, this is the first report of a dentigerous cyst showing SOT-LP features in the maxilla. Such cysts should be identified to avoid misdiagnosis, with the finding having therapeutic and prognostic implications.

Diagnosis and Treatment of an Odontogenic Epithelial Tumor in a Dog With Features of Squamous Odontogenic Tumor.

A 9-year-old standard poodle presented for a comprehensive oral health assessment and treatment, at which time a left rostral mandibular swelling was recognized. The mass was biopsied and eventually excised by a left rostral mandibulectomy en bloc resection. Histopathology supported the diagnosis of a benign, intraosseous, epithelial tumor that was otherwise unclassified. The clinical, radiological, and histological features of this case are similar to those reported for squamous odontogenic tumor (SOT) in humans. This case study relays the diagnosis, treatment, and follow-up of the first SOT-like tumor in a dog.

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.

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.

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.

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.

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.

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.

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.

Expresión del ki-67, p53, p16 y bcl-2 en Ameloblastomas / Expression of ki-67, p53, p16 and bcl-2 in Ameloblastomas

El objetivo de la presente investigación fue determinar la expresión de Ki-67, p53, p 16 y bcl-2 en Ameloblastoma Sólido y Uniquístico. El presente estudio fue retrospectivo de tipo clínico-patológico, experimental y correlacional. Se realizó análisis clínico-patológico de las variables: género, grupos de edad, diagnóstico histopatológico y localización anatómica y análisis inmunohistoquímico siguiendo protocolo estandarizado utilizando los marcadores Ki-67, p16, p53 y bcl-2 en el Laboratorio de Histopatología Bucal "Dr. Pedro Tinoco" de la Facultad de Odontología de la Universidad Central de Venezuela durante el período 2008-2013. De las biopsias bucomaxilofaciales se tomaron como muestra 34 casos diagnosticados histopatológicamente como Ameloblastoma Uniquístico (16 casos), Ameloblastoma Sólido (9 casos), y 9 casos como control con el diagnóstico de Tumor Odontogénico Queratoquístico. Se realizó análisis estadístico para correlación de variables a través de la prueba Kruskall-Wallis empleando Software estadístico SPSS®Versión N° 20 para sistema MAC OSX con un nivel de significancia del 99% (p<0,01). Se observó predominio del género masculino entre la segunda y tercera década de vida. Localización anatómica más frecuente en sector posterior mandibular, diagnóstico histopatológico más frecuente ameloblastoma uniquístico. El análisis inmunohistoquímico reveló al marcador Ki-67 como la más expresada, seguida por p53, bcl-2 y p16 indicando transformación neoplásica y proliferación asociado a tasa de recidiva Los marcadores utilizados son de utilidad para evaluar comportamiento biológico para sugerir tratamiento quirúrgico adecuado en cada caso.

The objective of this research was to determine the expression of Ki-67, p53, p16 and bcl-2 Solid and unicystic Ameloblastoma.This study was retrospective clinicopathological, experimental and correlational. Clinico-pathological analysis of the variables were: gender, age, anatomical site and histopathological diagnosis and immunohistochemical analysis using standardized protocol following the Ki-67, p16, p53 and bcl-2 markers in the Laboratory of Oral Histopathology "Dr. Pedro Tinoco "of the Faculty of Dentistry, Central University ofVenezuela during the period 2008-2013.The maxillofacial biopsies were sampled 34 cases diagnosed histopathologically as Ameloblastoma unicystic (16 cases), Ameloblastoma Solid (9 cases), and 9 cases as control diagnosis Odontogenic Tumor Queratoquístico statistical analysis for correlation of variables was performed through the Kruskal-Wallis test using SPSS statistical software version No. 20 MAC OSX system with a significance level of 99% (p <0.01).often males between the second and third decade of life was observed. Most frequent anatomical location in mandibular posterior, more frequent histopathological diagnosis unicystic ameloblastoma. Immunohistochemical analysis revealed the marcador Ki-67 as the expressed, followed by p53, bcl-2 and p16 indicating neoplastic transformation and proliferation associated with recurrence rate markers used are useful for assessing biological behavior to suggest appropriate surgical treatment in each case.

Prevalencia de ameloblastoma en una población peruana durante 13 años de evaluación / Prevalence of ameloblastoma in a peruvian population in 13 years of evaluation

Determinar la prevalencia de ameloblastoma en el Servicio de Cirugía de Cabeza y Cuello del Hospital Nacional Dos de Mayo, durante el periodo enero 1998 û julio 2012. Materiales y métodos. El diseño de investigación fue observacional, descriptivo, de tipo retrospectivo y transversal. La información fue recolectada de historias clínicas de pacientes con diagnóstico de ameloblastoma que se realizaron todo el tratamiento dentro del Hospital (preoperatorio, cirugía, posoperatorio y evolución). Resultados. Se determinó que el mayor número de casos se presentó durante la tercera década de vida, el sexo masculino predominó con un 90%, el sector más afectado fue el posterior mandibular con un 70 %, la resección tumoral en bloque fue el tipo de procedimiento más utilizado con un 40%, ningún caso reportó recidivas. Se determinó que el signo principal fue el incremento de volumen y dolor con un 80 y 50% respectivamente, el tamaño promedio del tumor estuvo comprendido entre 6 û 10 cm de longitud,solo el 10% de los casos fueron de evolución desfavorable. Conclusiones. Se encontró que el ameloblastoma es un tumor poco frecuente, se presenta, en promedio, un caso por año y está presente con mayor frecuencia en pacientes varones de raza mestiza entre 21 û 30 años procedentes de la costa peruana, este tumor mide en promedio 6-10 cm de largo por 1-5 cm de alto, estando ubicado con mayor frecuencia en la zona posterior mandíbular, siendo su cuadro clínico es el aumento de volumen seguido de dolor y movilidad dentaria...

To determine the prevalence of ameloblastoma at the Surgery Service of Head and Neck of the Dos de Mayo National Hospital during the period of January 1988-july 2012. Materials and methods. The research design of this study was retrospective. The information was collected from medical records with a diagnosis of ameloblastoma that were made throughout the treatment in the Hospital (Pre- surgery, surgery, post- surgery and evolution). Results. We found that the largest number of cases occurred during the third decade of life ,the male sex had a predominance of 90%, the sector most affected was the mandibular posterior area with 70%, tumor resection still block the most common type of procedure corresponding to 40%, no case reported recurrence . It was determined that the main sign was the increase in volume and pain occurring in 80% and 50% of cases respectively, the averagetumor size could be determined between 6 to 10 cm long, only 10% of cases were still unfavorable. Conclusions. We found that the ameloblastoma is a rare pathology, occurring in an average of 1 case per year, being present more frequently in male patients of mixed race between 21 to 30 years old from the Peruvian coast, we found this pathology average length 6-10 cm long and 1-5 cm high, being more frequently located in the posterior mandible, and its predominant clinical volume increase followed by pain and tooth mobility...

The large intracellular loop of ptch1 mediates the non-canonical Hedgehog pathway through cyclin B1 in nevoid basal cell carcinoma syndrome.

Mutations in the transmembrane receptor patched homolog 1 (Homo sapiens) (ptch1) are responsible for nevoid basal cell carcinoma syndrome (NBCCS), an autosomal dominant disorder that causes developmental abnormalities and predisposes the affected individuals to cancer. Many of these mutations, including mutations in the C-terminus of the large intracellular loop (ICL) of ptch1 (p.C727VfsX745 and p.S733IfsX736), result in the premature truncation of the protein. The ptch1­C727VfsX745 and ptch1-S733IfsX736 mutations have been identified in patients with NBCCS­associated keratocystic odontogenic tumors (KCOTs). In the present study, we found that the molecular mechanisms regulated by the non-canonical Hedgehog (Hh) signaling pathway through cyclin B1 are involved in the pathogenesis of NBCCS-associated KCOTs. In contrast to wild-type ptch1, ptch1-C727VfsX745 and ptch1­S733IfsX736 clearly exhibited reduced binding to cyclin B1. Moreover, the cells expressing these two mutations demonstrated an increase in cell cycle progression and these two mutation constructs failed to inhibit cell proliferation. In addition, the mutants enhanced the activity of glioma-associated oncogene family zinc finger 1 (GLI1), a downstream reporter of Hh signaling. Thus, our data suggest that the non-canonical Hh pathway mediated through ptch1 and cyclin B1 is involved in the pathogenesis of NBCCS-associated KCOTs. The C-terminus of ICL in ptch1 may also be a potential therapeutic target in the treatment of this disease.