Rare Case of Recurrent Adamantinoma of the Tibia: Limited Efficacy of Pazopanib as a Standalone Treatment.

BACKGROUND Adamantinoma is a rare low-grade malignant bone tumor, usually found in the tibial diaphysis and metaphysis, with histological similarities to mandibular ameloblastoma. The most effective treatment of recurrent adamantinoma is not yet clear. This report is of a 22-year-old woman with recurrent tibial adamantinoma treated with the tyrosine kinase inhibitor pazopanib. CASE REPORT We report the case of a 22-year-old woman who was referred to our center for a suspicious bone lesion in the right tibia. Bone biopsy findings were consistent with an adamantinoma. En bloc resection was completed successfully, with no postoperative complications. Five years later, a positive emission tomography scan revealed mildly increased tracer uptake near the area of the previous lesion and in the right inguinal lymph node. Biopsies of the lesion and inguinal lymph node confirmed recurrence of the adamantinoma. Due to abdominal and pelvic metastasis, the patient underwent surgical debulking, along with an appendectomy, right salpingo-oophorectomy, intraoperative radiation therapy, and hyperthermic intraperitoneal chemotherapy. Subsequently, the patient was placed on pazopanib for 4 months; however, her tumor continued to worsen after 4 months of chemotherapy. Currently, the patient is receiving gemcitabine and docetaxel as second-line medical therapy. CONCLUSIONS This report showed that pazopanib as standalone treatment does not appear to have promising role on patient outcomes. To the best of our knowledge, this is the second report of pazopanib in the treatment of adamantinoma.

Giant Mandibular Ameloblastoma with Rare Hypercalcemia: A Case Report and Literature Review.

Ameloblastoma is the most common benign odontogenic tumor with local invasion and high recurrence, which generally occurs in the jaw bones. Hypercalcemia is a common paraneoplastic syndrome that is commonly observed in patients with malignancies but rarely encountered in patients with benign tumors. Thus far, not many cases of ameloblastoma with hypercalcemia have been reported, and the pathogenic mechanism has not been studied in depth. This paper presents a case report of a 26-year-old male diagnosed with giant ameloblastoma of the mandible, accompanied by rare hypercalcemia. Additionally, a review of the relevant literature is conducted. This patient initially underwent marsupialization, yet this treatment was not effective, which indicated that the selection of the appropriate operation is of prime importance for improving the prognosis of patients with ameloblastoma. The tumor not only failed to shrink but gradually increased in size, accompanied by multiple complications including hypercalcemia, renal dysfunction, anemia, and cachexia. Due to the contradiction between the necessity of tumor resection and the patient's poor systemic condition, we implemented a multi-disciplinary team (MDT) meeting to better evaluate this patient's condition and design an individualized treatment strategy. The patient subsequently received a variety of interventions to improve the general conditions until he could tolerate surgery, and finally underwent the successful resection of giant ameloblastoma and reconstruction with vascularized fibular flap. No tumor recurrence or distance metastasis was observed during 5 years of follow-up. Additionally, the absence of hypercalcemia recurrence was also noted.

A Large Follicular Adenomatoid Odontogenic Tumor Occupying the Maxillary Sinus: A Case Report.

Adenomatoid odontogenic tumour is a rare benign, odontogenic tumour with uncertain histogenesis. Whether it is a hamartoma or a neoplasm is still a controversial topic. It is usually associated with an unerupted maxillary canine. Here, we discuss a follicular adenomatoid odontogenic tumour in a young girl with uncommon features such as it arose from two unerupted teeth and partial resorption of the roots of other normal teeth. The tumour was large enough to completely occupy the maxillary sinus. It was treated with enucleation and curettage by lateral rhinotomy approach. Keywords: adenomatoid tumor; case reports; hamartoma; odontogenic cysts.

Hypoproteinemia Associated with a Gigantic Odontogenic Tumor: A Report of 2 Cases.

BACKGROUND Hypoproteinemia is caused by a decrease in protein level in the blood. This report describes 2 cases of hypoproteinemia associated with a gigantic odontogenic tumor. CASE REPORT Case 1, a 65-year-old man, visited our hospital with the chief concern of swelling in the right mandible, approximately 100 mm in diameter, and ameloblastoma was diagnosed. Abscess drainage was observed in the fistula of the tumors. Total protein and albumin levels were low before surgery. Hemimandibulectomy was performed under general anesthesia. The final pathological diagnosis based on the specimen was ameloblastic carcinoma. After surgery, the total protein and albumin levels improved and remained stable 6 months after the operation. At 21 months after surgery, there were no signs of recurrence. Case 2, a 60-year-old woman, visited our hospital with a chief concern of swelling in the left mandible, approximately 100 mm in diameter, and ameloblastoma was diagnosed. Abscess drainage was observed in the fistula of the tumors. The patient had a history of hypoproteinemia; preoperative levels of total protein and albumin were low, and edema of the body was observed before surgery. Hemimandibulectomy was performed under general anesthesia. The final pathological diagnosis based on the specimen was ameloblastoma. After surgery, the total protein and albumin levels improved, and remained stable 6 weeks after surgery. There were no signs of recurrence 9 months after surgery. CONCLUSIONS These 2 cases indicate the possibility that hypoproteinemia can be caused by plasma leakage from fistulas associated with gigantic odontogenic tumors.

Bioengineering the ameloblastoma tumour to study its effect on bone nodule formation.

Ameloblastoma is a benign, epithelial cancer of the jawbone, which causes bone resorption and disfigurement to patients affected. The interaction of ameloblastoma with its tumour stroma drives invasion and progression. We used stiff collagen matrices to engineer active bone forming stroma, to probe the interaction of ameloblastoma with its native tumour bone microenvironment. This bone-stroma was assessed by nano-CT, transmission electron microscopy (TEM), Raman spectroscopy and gene analysis. Furthermore, we investigated gene correlation between bone forming 3D bone stroma and ameloblastoma introduced 3D bone stroma. Ameloblastoma cells increased expression of MMP-2 and -9 and RANK temporally in 3D compared to 2D. Our 3D biomimetic model formed bone nodules of an average surface area of 0.1 mm2 and average height of 92.37 [Formula: see text] 7.96 µm over 21 days. We demonstrate a woven bone phenotype with distinct mineral and matrix components and increased expression of bone formation genes in our engineered bone. Introducing ameloblastoma to the bone stroma, completely inhibited bone formation, in a spatially specific manner. Multivariate gene analysis showed that ameloblastoma cells downregulate bone formation genes such as RUNX2. Through the development of a comprehensive bone stroma, we show that an ameloblastoma tumour mass prevents osteoblasts from forming new bone nodules and severely restricted the growth of existing bone nodules. We have identified potential pathways for this inhibition. More critically, we present novel findings on the interaction of stromal osteoblasts with ameloblastoma.

Hemimandibulectomía por ameloblastoma multiquístico. A propósito de un caso / Multicystic ameloblastoma hemimandibulectomy. A propos of a case

RESUMEN El ameloblastoma es un tumor odontogénico benigno, localmente agresivo y recidivante, con predilección por la región posterior de la mandíbula. Se caracteriza por su agresividad local con muy baja tendencia a metastizarse. El objetivo fue reportar el caso clínico de un paciente con ameloblastoma multiquístico derecho, tratado a través de hemimandibulectomía. Se presentó un paciente masculino, de 44 años de edad, que refirió aumento de volumen del lado derecho de la mandíbula desde hacía aproximadamente un año, acompañado también de otros síntomas, atendido en el Servicio de Cirugía Maxilofacial del Hospital Militar Principal/Instituto Superior, en Luanda, Angola. Los estudios imagenológicos incluyeron radiografía panorámica y tomografía axial computarizada. El diagnóstico clínico patológico fue de ameloblastoma multiquístico. Este tipo de tumor requiere de un adecuado diagnóstico sobre la base de la presentación clínica, localización, tamaño, edad y tipo histológico; de ahí la importancia de conocer las características clínicas e imagenológicas, pues el tratamiento conlleva gran dificultad (AU).

ABSTRACT Ameloblastoma is a benign odontogenic tumor, locally aggressive and recidivist with predilection for back of the jaw, characterized by local aggressiveness and low tendency to metastasize. The aim was reporting the clinical case of a patient with right multicystic ameloblastoma treated through hemimandibulectomy. We presented a male patient aged 44 years, who referred a volume increase of the jaw right side for around a year, accompanied also by other symptoms; he attended the Maxillofacial Surgery Service of the Main Military Hospital/High Institute of Luanda, in Angola. The image studies included panoramic radiography and computerized axial tomography the clinical pathological diagnosis was multicystic ameloblastoma. This kind of tumor requires an adequate diagnosis based on the clinical presentation, location, size, age and histological kind, therefore the importance of knowing the clinical and image characteristics, because the treatment is very difficult (AU).

Fibula osteal flap with proximal peroneal perforator skin paddle for composite oromandibular reconstruction: A case report.

RATIONALE: Cutaneous perforators of peroneal vessels are divided into proximal and distal perforators on the basis of perforator distributions and musculocutaneous or septocutaneous properties. The traditional fibular osteocutaneous free flap is raised over the distal two-thirds of the fibula with a skin paddle based on distal perforators, which is affixed to the posterior crural septum. However, the skin pedicle may not be available due to anatomic variations or intraoperative injuries. Herein, because of the absence of distal perforators, we reserved and expropriated proximal perforators originating from the musculocutaneous branch of the superior part of the peroneal artery before it divided into nutrient and arcuate arteries and successfully harvested a separate osteal fibula and proximal perforator skin paddle with a single vascular pedicle-peroneal vessel. PATIENT CONCERNS: A 62-year-old man with a 6-month history of mandibular swelling and soft tissue invasion was referred to us. DIAGNOSIS: Panoramic radiography and computed tomography showed an irregular radiolucent lesion of the mandibular body, and histopathological analysis confirmed a follicular-pattern ameloblastoma. INTERVENTIONS: The diseased mandible and soft tissue were resected and reconstructed with a vascularized fibular osteal flap with the proximal perforator skin paddle. OUTCOMES: The mandibular contour was successfully restored; the skin paddle in the mouth was in good condition after 8 months of follow-up. LESSONS: The proximal perforator is reliable and practical for supplying a skin paddle and has significant potential for future applications. We recommend reserving the proximal perforator skin paddle as a backup flap when planning to raise a fibula flap, since unavailability or injury of the traditional fibular skin island based on distal perforators occurs frequently. This approach can avoid the exploration for a second donor site, save surgical time, and reduce surgical complexity. Moreover, we anticipate more frequent use of the proximal perforator flap in the future because of its flexibility and large volume, and since it can be combined with the osteal fibula or fibular osteocutaneous flap. However, an understanding of the traits of the proximal perforator and determination of its peroneal origin by computed tomography angiography is crucial for predesigning fibular osteal flaps with a proximal perforator skin paddle.

Pulmonary Malignant Ameloblastoma without Local Recurrence 31 Years after Primary Resection: A Case Report and Literature Review.

A 78-year-old man with a history of surgical resection for ameloblastoma 31 years earlier visited our hospital for prolonged cough. Chest computed tomography showed multiple nodules in both lungs. Although there was no local recurrence in the mandible, the specimen taken from a transbronchoscopic bronchial biopsy showed recurrent ameloblastoma. Despite receiving no treatment, the disease in our patient remained clinically stable for 8.4 years. Chest physicians should be aware that pulmonary malignant ameloblastoma can first relapse several decades after curative surgery. In addition, pulmonary malignant ameloblastoma without local recurrence may be associated with a good prognosis.

[A Case of Malignant Ameloblastoma Associated with Uncontrollable Hypercalcemia].

Approximately 20-30% of cancers are associated with hypercalcemia, and this is a complication often encountered in cancer care. Hypercalcemia causes disorders such as disturbance of consciousness and, in severe cases, kidney failure and even death. In this report, we present a case of malignant ameloblastoma associated with uncontrollable hypercalcemia followed by a life-threatening disease course. In this case, hypercalcemia shortened the period of home care, and the medical staff could have extended this period by acquiring knowledge that leads to early detection and better control of hypercalcemia. In addition, the choice of the place for end-of-life care may have been expanded by considering the treatment of not only the malignant tumor but also hypercalcemia as its complication.

Upregulation of interleukin-8 and activin A induces osteoclastogenesis in ameloblastoma.

Ameloblastoma is a common odontogenic benign tumor located in the jaws and is characterized by severe local bone destruction. The current study aimed to investigate the effect of interactions between tumor cells and bone marrow stromal cells (BMSCs) on osteoclast formation in ameloblastoma. The impact of ameloblastoma/BMSC interactions on cytokine production, gene expression and osteoclastogenesis was examined using an immortalized ameloblastoma cell line that the authors' previously established. The results demonstrated that interactions between ameloblastoma cells and BMSCs increased interleukin (IL)­8 and activin A secretion by BMSCs. IL­8 expression in BMSCs was modulated by tumor­derived tumor necrosis factor­α and IL­8 contributed to osteoclast formation not only directly but also by stimulating receptor activator of NF­κB ligand (RANKL) expression in BMSCs. Activin A secretion in BMSCs was stimulated by ameloblastoma cells via cell­to­cell­mediated activation of c­Jun N­terminal kinase activation, acting as a cofactor of RANKL to induce osteoclast formation and function. The present study highlights the critical role of communication between BMSCs and ameloblastoma cells in bone resorption in ameloblastoma.

Hybrid ameloblastoma: a mystified histopathological entity.

Ameloblastoma a benign neoplasm of the maxillofacial region has been divided into various histopathological types by WHO. A more complex and confusing type includes hybrid type, which as the name suggest include more than two variants mostly histopathological. Various authors have reported cases of this type but the exact histopathological features are still unclear and each case that is being reported add to the literature, which further strengthens its histopathological feature. Also, this is a lesion whose clinical and radiographical features are similar to all the variants and a definitive diagnosis is achieved by histopathology only. Here, we present a case of hybrid ameloblastoma with striking and unique histopathological features.

RBM10 truncation in astroblastoma in a patient with history of mandibular ameloblastoma: A case report.

Astroblastoma is a rare glial neoplasm composed of cells that have broad processes oriented perpendicular to central vessels and often demonstrate vascular sclerosis. The WHO 2016 classification does not specify a grading system for astroblastoma, and categorizes them as well-differentiated or malignant. These broad classification rubrics, however, do not accurately predict clinical outcome. Genetic profiling of astroblastoma has therefore been of particular interest in the recent years. These efforts, although in small number, have revealed heterogeneous molecular findings that may explain astroblastoma's unpredictable clinical outcome. Here, we report a case of recurrent astroblastoma in a 23-year-old female with a unique molecular characteristic. Our patient's tumor harbored an RNA-binding motif 10 (RBM10) truncation. RBM10 codes for a widely expressed RNA binding protein, and its mutation has been described in a variety of solid cancers. RBM10 is thought to be involved in stabilization of pro-apoptotic proteins in breast cancer, and its reduced protein expression is associated with advanced stages of lung adenocarcinoma. To our knowledge, this is the first report of astroblastoma harboring RBM10 truncation. Interestingly, our patient also has a history of mandibular ameloblastoma, but the link between these two rare tumors is unclear.

The Epidemiology, treatment, and complication of ameloblastoma in East-Indonesia: 6 years retrospective study.

BACKGROUND: Ameloblastoma is a neoplasm classified as a benign epithelial odontogenic tumor of the jaws, grow slowly and are locally invasive. The aim of the present study was to investigate the incidence, treatment, and complication of patients with ameloblastoma in East-Indonesia during six years retrospective study. MATERIAL AND METHODS: This retrospective study included 84 patients who were diagnosed with ameloblastoma from 2011 to 2016. There were 56 patients with treatment data available. Data from each patient, including gender, age, histologic type, the size of the tumor, radiologic form, tumor location, type of treatment, and complication were reviewed and analyzed retrospectively. RESULTS: Fourteen patients were diagnosed with unicystic ameloblastoma (25%), thirty two patients with multicystic follicular ameloblastoma (57%) and ten patients with an unspecified multicystic ameloblastoma (18%). A total of about 35 patients were treated conservatively (62.5%) and 21 patients were treated radically (37.5%). Swelling was present as a pre-operative complication in all 56 cases (100%). There were no complaints concerning speech. CONCLUSIONS: The majority findings of the histologic type were multicystic ameloblastoma and their location were in the mandible. Most ameloblastoma were treated conservatively and reconstructions were made with only titanium plates and not bone graft.

Longitudinal Perioperative Pain Assessment in Head and Neck Cancer Surgery.

OBJECTIVE: To evaluate perioperative pain in patients undergoing major head and neck cancer surgery and identify associations between preoperative and postoperative pain characteristics. METHODS: Patients undergoing head and neck surgery with regional/free tissue transfer were enrolled. Preoperative pain and validated screens for symptoms (neuropathic pain, anxiety, depression, fibromyalgia) were assessed. Postoperatively, patients completed a pain diary for 4 weeks. RESULTS: Twenty-seven patients were enrolled. Seventy-eight percent had pain prior to surgery, and for 38%, the pain had neuropathic characteristics. Thirteen patients (48%) completed at least 2 weeks of the postoperative pain diary. Patients with moderate/severe preoperative pain report significantly greater pain scores postoperatively, though daily pain decreased at a similar linear rate for all patients. Patients with more severe preoperative pain consumed greater amounts of opioids postoperatively, and this correlated with daily postoperative pain scores. Patients who screened positive for neuropathic pain also reported worse postoperative pain. CONCLUSION: Longitudinal perioperative pain assessment in head and neck patients undergoing surgery suggests that patients with worse preoperative pain continue to endorse worse pain postoperatively and require more narcotics. Patients with preoperative neuropathic pain also report poor pain control postoperatively, suggesting an opportunity to identify these patients and intervene with empiric neuropathic pain treatment.

Eruption of an impacted canine in an adenomatid odontogenic tumor treated with combined orthodontic and surgical therapy.

An adenomatoid odontogenic tumor is an uncommon asymptomatic lesion that is often misdiagnosed as a dentigerous cyst. It originates from the odontogenic epithelium. Enucleation and curettage is the usual treatment of choice. Marsupialization may be attempted instead of extraction of the impacted tooth, since it provides an opportunity for tooth eruption. This case report is the first to report on the eruption of an impacted canine in an adenomatoid odontogenic tumor treated with combined orthodontics and marsupialization. The impacted canine erupted uneventfully, with no evidence of recurrence 3 years after the treatment.

A rare variant of calcifying odontogenic cyst with ameloblastoma presentation.

Calcifying odontogenic cyst is a rare entity which was first described by Gorlin, and also accounts for 1% of the jaw cysts according to Shear. Due to its diverse histopathology and variable clinical features, there has been a doubt regarding its nature as a cyst or a neoplasm. In this report we present a case of calcifying odontogenic cyst with mural ameloblastomatous presentation in the left body of the mandible in a 19-year-old male patient. This is the 15th case of ameloblastomatous COC being documented in literature.

Avaliação da expressão imuno-histoquímica das proteínas p53 e pRB em ameloblastomas e tumores odontogênicos queratocísticos / Evaluation of immunohistochemistry expression of the proteins p53 and pRB in ameloblastomas and keratocystic odontogenic tumorP

Tumores odontogênicos constituem grupo abrangente de afecções tumorais, sendo ameloblastomas e tumores odontogênicos queratocísticos as lesões benignas de maior frequência, cujas características biológicas são pouco conhecidas. Objetivo do presente estudo foi avaliar o perfil imuno-histoquímico das proteínas pRB e p53 em ameloblastoma e tumor odontogênico queratocístico. Foram avaliadas amostras de material parafinado de 21 casos de ameloblastoma e de 20 casos de tumor odontogênico queratocístico para ensaio de imuno-histoquímica com os anticorpos anti-pRB e anti-p53. A contagem da imuno-marcação foi realizada a partir de fotografias de alta resolução processadas no software ImageJ para quantificação manual em campo de 1000 células. A localização da imuno-marcação para ambos anticorpos foi semelhante, sendo em ameloblastomas predominantemente nas células da periferia e, em tumores odontogênicos queratocísticos, nas camadas suprabasais. Quantitativamente, as porcentagens de células marcadas foram estatisticamente maior nos ameloblastoma para anti-p53 (p=0,01) e maior nos tumores odontogênicos queratocísticos para anti-pRB (p=0,04). Não houve correlação estatística entre a porcentagem de células marcadas para anti-p53 e anti-pRB nos ameloblastomas, porém, esta correlação foi positiva e moderada nos tumores odontogênicos queratocísticos (r=0,537; p=0,018). Nota-se ligeira diferença na quantificação das imuno-marcações para o anti-p53 e anti-pRB. Tais resultados devem ser ponderados pela reduzida casuística, porém, sugerem perfis distintos em mecanismos biológicos determinantes para ambos os tumores.

Odontogenic tumors are a comprehensive group of tumor diseases, being ameloblastomas and keratocystic odontogenic tumors the most frequent benign odontogenic tumors. Their biological characteristics are little unknown. The aim of present study was to evaluate the immunohistochemical profile of pRB and p53 proteins in 21 cases of ameloblastomas and 20 cases of keratocystic odontogenic tumors for anti-pRB and anti-p53 antibodies. The quantification of immunostaining was performed manually with high-resolution photographs processed in the ImageJ software to quantify positive cells in a 1000 cells-field. The location of immunostaining for both antibodies was similar. In ameloblastomas, positive cells are located mainly in the peripheral layers, whereas in keratocystic odontogenic tumors the positive cells are located in the suprabasal layers. Quantitatively, the percentage of labeled cells was statistically higher in ameloblastomas for anti-p53 (p = 0.01) and higher in keratocystic odontogenic tumors for anti-pRB (p = 0.04). There was no statistical correlation between the percentage of labeled cells to anti-p53 and anti-pRB in ameloblastomas, however, its correlation was positive and moderate in keratocystic odontogenic tumors (r = 0.537; p = 0.018). It is possible to identify a slight difference in immuno-quantification for anti-p53 and anti-pRB among these lesions. These results must be pondered by the small sample, however, is suggests a different profile in a preponderant key biological mechanisms for odontogenic tumors.

Estudo clinicopatológico retrospectivo dos casos de tumores odontogênicos diagnosticados no Serviço de Patologia Cirúrgica da FOUSP no período de 1957 a 2012 / Retrospective clinicopathological study of cases of odontogenic tumors diagnosed in the FOUSP Surgical Pathology Service in 1957 and 2012

Os tumores odontogênicos formam um grupo complexo de lesões, de comportamento clínico variado e encontrado exclusivamente na região bucomaxilofacial. Originam-se a partir das células que normalmente teriam a função de formar o dente, processo esse denominado odontogênese, que tem seu início entre a sexta e a sétima semanas de vida intrauterina. O objetivo deste trabalho foi realizar um estudo clinicopatológico de tumores odontogênicos diagnosticados no Serviço de Patologia Cirúrgica da Faculdade de Oodontologia da Universidade de São Paulo de 1957 a 2012. Foram compilados das fichas de requisição de exames e/ou prontuários dados referentes ao sexo, idade no momento do diagnóstico, cor da pele (branca, negra, ou outras), sintomatologia, tamanho da lesão, duração, localização anatômica, aspectos radiográficos, diagnóstico clínico e histopatológico. Os casos diagnosticados como tumores odontogênicos foram revisados, por um examinador previamente calibrado, com o objetivo de reclassificação das lesões conforme proposição atual da Organização Mundial da Saúde em 2005. Todos os dados obtidos foram inseridos e tabulados no Microsoft Office Excel 2013 e analisados no software BioEstat 5.0. Medidas de frequência central e de dispersão foram obtidas e os resultados apresentados em forma de tabelas e gráficos. Na análise estatística, foi empregado o teste Z de duas proporções com nível de significância de 5%. No período compreendido de 01 de janeiro de 1957 a 31 de dezembro de 2012, foram diagnosticados 2.114 casos de tumores odontogênicos.

Do total de casos diagnosticados, 75 casos foram retirados da análise, pois representavam a mesma lesão em diferentes momentos. Portanto, 2.039 casos de tumores odontogênicos foram incluídos e, após revisão dos casos e reclassificação diagnóstica dos tumores odontogênicos, os 2.039 casos foram agrupados em 16 tipos histológicos diferentes, entre os quais 2.029 (99,51%) eram benignos e 10 (0,49%) malignos. De uma maneira geral, os tumores odontogênicos afetam pacientes na segunda e terceira décadas de vida, sem predileção por sexo, apresentam-se menores do que 1cm de diâmetro e são diagnosticados, em média, 2 anos após seu surgimento. A maioria das lesões acometem a região posterior da mandíbula, com exceção do odontoma e tumor odontogênico adenomatóide, e apresentam aspecto radiográfico radiolúcido inespecífico, o que dificulta um diagnóstico preciso sem a avaliação anatomopatológica.

Odontogenic tumors are a complex group of lesions, varied clinical behavior and found exclusively in the oral and maxillofacial region. Originate from cells that would normally have the function of forming the tooth, a process called odontogenesis, which begins between the sixth and seventh weeks of intrauterine life. The aim of this study was a clinicopathological study of odontogenic tumors diagnosed in Surgical Pathology Service of Oodontologia of the University of São Paulo from 1957 to 2012 were compiled from surveys of request forms and / or records data on gender, age at diagnosis, skin color (white, black, or other), symptoms, lesion size, duration, anatomic location, radiographic findings, clinical and histopathological diagnosis. The cases diagnosed as odontogenic tumors were reviewed by a calibrated examiner, in order to reclassify injuries as current proposition of the World Health Organization in 2005. All data were entered and tabulated in Microsoft Office Excel 2013 and analyzed in software BioEstat 5.0. Central frequency and dispersion measurements were obtained and the results presented in tables and graphs. In the statistical analysis, we used the Z test for similar proportions with 5% significance level. In the period of January 1, 1957 to December 31, 2012 were diagnosed 2,114 cases of odontogenic tumors. Of all diagnosed cases, 75 cases

were removed from the analysis because they represented the same injury at different times. Therefore, 2,039 odontogenic tumors were included and, after review of the cases and diagnostic reclassification of odontogenic tumors, 2,039 cases were grouped into 16 different histological types, including 2 029 (99.51%) were benign and 10 (0, 49%) malignant. In general, the odontogenic tumors affect patients in the second and third decades of life, with no gender preference, are presented less than 1cm in diameter and are diagnosed on average two years after its inception. Most injuries involve the posterior mandible, except for the odontoma and adenomatoid odontogenic tumor, and feature radiolucent radiological findings nonspecific, which hinders accurate diagnosis without pathological assessment.

Peripheral ameloblastoma with dystrophic calcification: an unusual feature in non-calcifying odontogenic tumors.

Peripheral ameloblastoma is a rare extraosseous counterpart of central ameloblastoma that occurs in soft tissues and may cause bone crest resorption. This study reports a peripheral ameloblastoma on the buccal gingiva of a 56-year-old man, which presented extensive squamous metaplasia areas, keratinization and dystrophic calcifications in the neoplastic islands. It is emphasized the need of a detailed imaging study and a long follow-up period to exclude bone involvement whenever peripheral ameloblastoma diagnosis is considered.