Molecular and Genetic Aspects of Odontogenic Lesions

In this article we outline the molecular findings of select odontogenic tumors. In each section, we briefly review selected the clinicoradiographic, histologic, immunologic features, focusing on the molecular findings and their applications in practice. The understanding of molecular pathobiology at various other organ sites has developed quite rapidly in recent years, however much remains unknown about the genetic profile of odontogenic tumors. Improved understanding of mutations in odontogenic tumors may clarify classification schema and elucidate targets for novel therapies. Molecular testing will no doubt improve our understanding of odontogenic tumor pathogenesis and will likely be, someday, an important component of routine clinical practice and its role will only increase in the coming years

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma: Report of a case in the oral cavity

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma (DLBCL/BL) is a new category of B-cell lymphoma according to the 4 th edition of the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues (2008). The following report presents a case of this rare, newly described entity on the palate of a 59 year-old male

Evaluation of SOX2 as a potential marker for ameloblastic carcinoma

ObjectiveAmeloblastic carcinoma often poses diagnostic challenges in its separation from benign ameloblastoma with atypical cytologic features or an unusual clinical course. This study aimed to determine whether SOX2 (sex determining region-Y-related high mobility group box 2), a protein expressed in the epithelial basal proliferative zone in dentigerous cysts, is a marker for ameloblastic carcinoma as well as for high-grade transformation in ameloblastic neoplasms.Study DesignImmunoperoxidase stains were performed according to a standard protocol. Immunostains were interpreted independently by 3 pathologists, and scores were recorded based on the percentage of staining and intensity of staining in the cells of interest.ResultsThe diffuse strong nuclear staining pattern has 86.4% specificity (19 of 22) to indicate the presence of high-grade features and has 76.9% sensitivity (10 of 13) in comparison with benign counterparts (P = .0021). Although previously shown as a marker for ameloblastic neoplasms, calretinin is weakly positive in a few cells in 50% (5 of 10) of ameloblastic carcinoma and 43% (3 of 7) of benign ameloblastic neoplasms, with little value in highlighting the high-grade change (P = .36).ConclusionsThe diffuse nuclear staining pattern of SOX2 is suggestive of a high-grade process in ameloblastic neoplasms. Numerous aggregates of cells harboring dense nuclear stain should raise concern for a malignancy

Oral Squamous Cell Carcinoma with Mandibular Bone Invasion: Intraoperative Evaluation of Bone Margins by Routine Frozen Section

The intraoperative knowledge of margin status on mandibulectomy specimens is important for primary reconstruction. The goal of this study was to evaluate whether intraoperative bone marrow (BM) curettings and inferior alveolar nerve (IAN) biopsies are representative of final decalcified cross-sectional (shave) mandibular bone margins. Forty-seven margins in 27 patients consecutively treated with segmental mandibulectomy for squamous cell carcinoma were reviewed. These patients had BM or IAN margins sampled by surgeons and assessed intraoperatively by routine frozen section. The full cross-section of mandibular bone margins were sampled by pathologists at the time of routine gross examination. Intraoperative evaluation of BM/IAN biopsies is characterized by a 50% sensitivity (3 of 6 cases were false negative) and a 100% specificity. IAN biopsies are representative of the final bone margin. Given the technical feasibility of intraoperative BM and IAN assessment, we favor routine intraoperative evaluation of mandibular bone margins. However, even when bone margins are sampled intraoperatively, obtaining a full cross-section of the bone margin at the time of gross examination should also be performed as it remains the most accurate modality of bone margin assessment