Evaluation of Paxillin Expression in Odontogenic Cysts and Tumors.

Statement of the Problem: Paxillin (PXN) is one of the proteins involved in cell adhesion. PXN and integrins constitute a key site for the focal adhesion between the cell and extracellular matrix. Several studies have shown that PXN is a factor in tumor formation, progression, invasion, and metastasis. Purpose: This study evaluated PXN expression in four types of odontogenic lesions with different aggressive behaviors. Materials and Method: In this retrospective cross-sectional study, PXN expression was immunohistochemically assessed in 68 paraffin-embedded tissue samples from patients with the confirmed diagnosis of four types of odontogenic lesions, including 14 dentigerous cysts (DC), 20 odontogenic keratocyst (OKC), 16 unicystic ameloblastoma, and 18 solid ameloblastoma. The PXN expression in these samples were scored based on the percentage and intensity of immunoreactivity, and compared among the groups by Chi-square test. Results: The PXN marker was detected in the cytoplasm of tumor cells (unicystic and solid ameloblastoma) and the epithelial layer of cysts (DC and OKC). The intensively stained marker of PXN was observed in 9 cases (64.3%) of the DC, 14 cases (70%) of OKC, 12 cases (75%) of unicystic ameloblastoma, and 13 cases (72.2%) of solid ameloblastoma. However, there was not statistical difference of PXN protein expression between DC and OKC (p Value = 0.51) and unicystic and solid ameloblastoma (p = 0.58), also the same was true for cysts and tumors (p = 0.37). Conclusion: The expression of PXN is not related to the biological behaviors of odontogenic lesions.

Ameloblastoma: Management and Outcome.

Introduction Ameloblastoma is a locally destructive tumor with a propensity for recurrence if not entirely excised. Management of ameloblastoma poses a challenge for all involved in the field of head and neck surgery because successful treatment requires not only adequate resection but also a functional and aesthetically acceptable reconstruction of the residual defect. Methods Patients who had histologically proven ameloblastoma between 1991 and 2009 were identified from the database of Aga Khan University Hospital. A review of all medical records, radiological images, operative reports and pathology reports was undertaken. Results A total of 15 patients with histologically confirmed ameloblastoma were identified. Out of 15 patients nine were males and six were females with age range from 20 to 60 years (mean age 43 years). The most common symptom found in our patient group was painless facial swelling. In 13 patients the origin of tumor was mandible and in the remaining two the tumor originated from maxilla. Eleven out of 15 patients underwent segmental mandibulectomy, two had maxillectomy and two had enucleation. All patients who underwent segmental mandibulectomy required reconstruction. Reconstruction was done with microsurgical free tissue transfer in eight patients, non-vascularized iliac crest bone graft was used in one patient and two had plating only. All free flaps survived with no evidence of flap loss. The mean follow-up was eight years. There was no evidence of graft failure which was used in one patient. Complication was seen in only one of our patients in the form of plate exposure. Recurrence was seen in two of our cases who primarily underwent enucleation. All patients had satisfactory speech, cosmesis and mastication. Conclusion The management of ameloblastoma still poses a big challenge in spite of being the most common odontogenic tumor. In our study we have found that segmental mandibulectomy with disease-free margin of around 1 cm and immediate reconstruction with free tissue transfer have shown good results.

Recurrence rates of intraosseous ameloblastomas of the jaws: a systematic review of conservative versus aggressive treatment approaches and meta-analysis of non-randomized studies.

BACKGROUND: The aim of the present study was to define and evaluate the post-treatment recurrence of unicystic and solid or multicystic ameloblastoma lesions, measured as counts of first time recurrences. METHODS: A systematic review of the literature and meta-analysis was planned according to the PRISMA statement and in order to include randomized and non-randomized clinical trials and observational studies in humans. Seven electronic databases were searched from their start up to December 2013 without limitation to year, language or publication status. RESULTS: A total of seven non-randomized studies with 229 cases of treated ameloblastoma lesions were included in the quantitative synthesis. The summary recurrence rate of ameloblastomas for the unicystic and solid or multicystic variants ranged from 0.2% to 12% and 0.8% to 38% respectively. The comparison of a conservative treatment approach versus radical in solid or multicystic ameloblastoma favored the radical. CONCLUSIONS: The absence of studies with low risk of bias precludes the making of strong clinical recommendations while resection may be preferable in both unicystic and solid or multicystic. ameloblastomas.

Evaluation and comparison of expression of p63 in odontogenic keratocyst, solid ameloblastoma and unicystic ameloblastoma.

BACKGROUND AND OBJECTIVES: The behavior of odontogenic lesions varies with some tumors behaving like a cyst and some cysts behaving like tumors. p63, a member of the p53 family of tumor suppressor genes has recently come into light in view of its role as an oncogene. The aim of the present study was to investigate the expression of p63 protein in OKC, Solid ameloblastoma, Unicystic Ameloblastoma and Follicular tissue. MATERIALS AND METHODS: p63 expression was compared in 12 cases of OKC, 12 Solid Ameloblastoma, 14 cases of Unicystic ameloblastoma and 10 cases of Follicular tissue using immunohistochemical technique. All 48 cases were subjected to heat-induced antigen retrieval method using citrate buffer in a pressure cooker. Then the sections were stained with anti-p63 polyclonal antibody and visualized using super sensitive polymer HRP detection system. In each case, number of cells showing p63 positivity were assessed in two compartments - basal and suprabasal and compared. RESULTS: Statistical analysis showed that p63 expression in the suprabasal compartment in Odontogenic keratocysts was equivalent to that of central neoplastic cells of Solid Ameloblastoma and Unicystic Ameloblastoma type 3. Statistically significant difference in the expression of p63 was observed between OKC and Unicystic Ameloblastoma Type 1 and Solid Ameloblastoma and Unicystic Ameloblastoma Type 1. CONCLUSION: We conclude that the higher expression of p63 in these odontogenic lesions correlates well with their aggressive behavior and thereby suggesting alterations in treatment modalities.

Mandibular ameloblastoma in a 10-year-old child: case report and review of the literature / Ameloblastoma mandibular en niño de 10 años: reporte de un caso y revisión de la literatura

The ameloblastoma according to the classification of odontogenic tumors by WHO in 2005, is classified as a benign neoplasm of odontogenic epithelial origin. One to three percent of tumors and cysts of the jaws are comprised of ameloblastomas. The tumor is locally aggressive, but often asymptomatic, showing a slow growth which is manifested as a facial swelling or radiographic incidental finding. On clinical examination, the tumor can cause symptoms such as pain, ulceration, tooth mobility, root resorption and malocclusion. Ameloblastomas have a high rate of recurrence if not completely removed. It occurs in almost all age groups, but is mainly diagnosed in the third or fourth decade of life. The tumor is very rare in children. We present an unusual case of a solid/multicystic ameloblastoma of the mandible in a 10-year-old girl. In addition, a brief review of the literature on reported cases of this pathology in children is also presented...

El ameloblastoma según la clasificación de tumores odontogénicos de la OMS del 2005 lo clasifica como una neoplasia benigna de origen epitelial odontogénico. Compromete el 1-3% de neoplasias y quistes maxilares. El tumor es agresivo localmente, pero muchas veces asintomático; presenta un lento crecimiento que se manifiesta como un aumento de volumen facial o un hallazgo incidental radiográfico. Al examen clínico el tumor puede causar síntomas como dolor, ulceración, reabsorción radicular con movilidad dentaria y maloclusión. El ameloblastoma posee gran tasa de recurrencia si no es totalmente removido. Se presenta en casi todos los grupos etarios pero principalmente se diagnostica en la tercera o cuarta década de vida, el tumor es muy poco común en niños. El tratamiento del ameloblastoma es controversial y debido a la distinta incidencia y comportamiento en niños, hace las consideraciones quirúrgicas diferentes a los adultos. Por lo que presentamos un inusual caso de un ameloblastoma solido/multiquístico mandibular en una niña de 10 años. Además de una breve revisión de la literatura sobre casos reportados de esta patología en niños...