Diagnosis of oral potentially malignant disorders: Overview and experience in Oceania

The diagnosis and management of oral potentially malignant disorders (OPMD) should be the same the world over, but there are important nuances in incidence, aetiological factors, and management opportunities that may lead to differences based on ethnogeography. In this review, we update and discuss current international trends in the classification and diagnosis of OPMD with reference to our experience in various regions in Oceania. Oceania includes the islands of Australia, Melanesia (including Papua New Guinea, Fiji, Solomon Islands, Micronesia and Polynesia (including New Zealand, Samoa, Tonga) and hence has diverse populations with very different cultures and a range from well-resourced high-population density cities to remote villages

Revisiting the association between candidal infection and carcinoma, particularly oral squamous cell carcinoma

Background: Tobacco and alcohol are risk factors associated with cancer of the upper aerodigestive tract, but increasingly the role of infection and chronic inflammation is recognized as being significant in cancer development. Bacteria, particularly Helicobacter pylori, and viruses such as members of the human papilloma virus family and hepatitis B and C are strongly implicated as etiological factors in certain cancers. There is less evidence for an association between fungi and cancer, although it has been recognized for many years that white patches on the oral mucosa, which are infected with Candida, have a greater likelihood of undergoing malignant transformation than those that are not infected. Objective: This article reviews the association between the development of oral squamous cell carcinoma in potentially malignant oral lesions with chronic candidal infection and describes mechanisms that may be involved in Candida-associated malignant transformation

A Double-Clear Variant of Epithelial-Myoepithelial Carcinoma of the Parotid Gland

The hallmark of the histology of epithelial-myoepithelial carcinoma (EMC) is the presence of a regular repetitive mixture of bilayered duct-like structures with an outer layer of myoepithelial cells and inner ductal epithelial cells. Clear cell change in the myoepithelial component is common, but clearing of both cell types, giving an impression of a monocellular neoplasm, is rare. A parotid biopsy was received from an 83-year-old male and subject to routine histologic processing for conventional staining and immunohistochemistry. The encapsulated tumour was composed of sheets of PAS/diastase negative clear cells, separated by fibrous septae. The clear myoepithelial cells were positive for S-100 protein, SMA, and p63 and negative for CK19 and surrounded CK19-positive luminal cells. It is important to utilise immunohistochemistry to differentiate this tumour from others with a similar histologic pattern. Information about the behaviour of the double-clear EMC is limited since there are few cases reported

Metastases to the oral region from pleural mesothelioma: Clinicopathologic review

Background Malignant mesothelioma is a rare neoplasm that usually develops after exposure to asbestos and particularly involves the pleural cavity. It has a poor prognosis with aggressive local invasion and metastatic spread. Methods The literature relating to malignant mesothelioma metastatic to the oral region was reviewed. Results In all, 14 cases of malignant mesothelioma metastatic to the oral cavity were found. All were from pleural mesotheliomas, the tongue was the most common site of metastasis (8/14), and most metastases (9/13) were of the epithelioid type. The newly reported case is only the second report of a mesothelioma metastasizing to the buccal mucosa. It showed strong immunopositivity for keratin markers, vimentin, calretinin, and Wilms tumor product-1. Conclusions The incidence of mesothelioma is predicted to continue to increase for at least another decade. Clinicians and pathologists should be aware of this lesion and its propensity to metastasize to the oral cavity. (c) 2011 Wiley Periodicals, Inc. Head Neck, 201

Potentiality and Inflammatory Marker Expression Are Maintained in Dental Pulp Cell Cultures from Carious Teeth

Objectives: This investigation aimed to isolate and culture human dental pulp cells from carious teeth (cHDPCs) and compare their growth characteristics, colony-forming efficiency, mineralization potential and gene expression of Toll-like receptors (TLR)-2, TLR-4, TLR-9, tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, IL-17A, 1L-17R, IL-23A, nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK1), dentin matrix protein (DMP)-1, dentin sialophospho protein (DSPP), sex determining region Y-box 2 (SOX2) and marker of proliferation Ki-67 (MKi67) with cells isolated from healthy or non-carious teeth (ncHDPCs). Methods: Pulp tissues were obtained from both healthy and carious teeth (n = 5, each) to generate primary cell lines using the explant culture technique. Cell cultures studies were undertaken by generating growth curves, a colony forming unit and a mineralization assay analysis. The expression of vimentin was assessed using immunocytochemistry (ICC), and the gene expression of above-mentioned genes was determined using quantitative real-time reverse-transcription polymerase chain reaction. Results: ncHDPCs and cHDPCs were successfully isolated and cultured from healthy and inflamed human dental pulp tissue. At passage 4, both HDPC types demonstrated a typical spindle morphology with positive vimentin expression. No statistical difference was observed between ncHDPCs and cHDPCs in their growth characteristics or ability to differentiate into a mineralizing phenotype. ncHDPCs showed a statistically significant higher colony forming efficiency than cHDPCs. The gene expression levels of TLR-2, TLR-4, TLR-9, TNF-α, IL-6, IL-8, IL-17R, IL-23A, NF-κB, MAPK1, DMP1, DSPP and SOX2 were significantly higher in cHDPCs compared with ncHDPC cultures. Conclusion: cHDPCs retain their differentiation potential and inflammatory phenotype in vitro. The inflamed tooth pulp contains viable stem/progenitor cell populations which have the potential for expansion, proliferation and differentiation into a mineralizing lineage, similar to cells obtained from healthy pulp tissue. These findings have positive implications for regenerative endodontic procedures