Epithelial myoepithelial carcinoma(EMC) is an uncommon malignant sali va ry gland neoplasm, compri sing about 1% 。f salivar y gland neoplasms, They are histologically composed 01' biphasic cell s such as myoepithelial cells and ductal cells EMC occurs predominantly in the major salivary glands, par t icularly in the par otid gland, They have been reported to occur onJy 10-15% in t he intraoral minor salivary glands, The authors experi enced 4 cases of EMC in Department of Oral Pathology in Seoul National University Dental Hospital from 1995 to 2007‘ and reported them with revi ew of li terature, They occurred at the age [rom 34 to 75 years with average age of 54, Three cases occurred in f'emale and 1 in male, showing predominant occurrence in female, Al I of them occurred in the f100r of mouth Three patients presented localized swollen mass at the time of admission, One patient manifested pain with surface n ecrotic ulcer, and others did not complain any symptoms, The duration of symptoms before diagnosis has ranged f rom three mont hs to 2 years in our cases Microscopically, they growed in double layered ductal structure composed 。f' ductal cells of the inner luminal layer which showed positive immunohistochemical reaction to cytokeratin and rnyoepithelial cells 01' the outer peripheral layer identifi ed by the positive reactivity to S-100 and srnooth muscle ac tin antibody, They did not show perinem al invasion‘ but invasíve growth into adjacent tissue, AII of them did not show in vasion into t he underlying bOl1e While 3 pat ients were treated with total excision of tω110 1' mass wi thout n。 evidence of recurrence a ncl metastasis, a 75 year old patient gave up receiving t reatment at the t irne of diagnos is, and then died 01' the cancer 5 years after init ial diagnosis, It seems that EMC of the intraoral minor salivary gland is a tumor 01' low grade malignancy with low potent ial of recurrence and metastasis

Oral squamous cel1 carcinoma(OSCC) is the most common malignancy of head neck region. Typically OSCC cells s how persist ent invasion that frequently leads to local recurrence and distant lymphatic metastasls However, molecular mechanisms of invasion of OSCC remain poorly understood. Her e we identifi ed periostin, interferon induced transmembrane protein l (IF1TM1) and wingless-type MMTV integration site family, member 5B(WNT5B) , as invasion promoting molecules in OSCC by comparing gene expression profiles between a parent OSCC cell line(MSCC-l) and its highly invasive clone(MSCC-1nvl). Overexpression of periostin, IFITMl and WNT5B mRNAs were confirmed in MSCC-1nvl by RT-PCR. Transfection of these molecules promoted invasion of OSCC cells Moreover , siRNA t r eatment of these molecules suppressed invasion of cancer cells in vitro I nter estingly, Periostin, 1F1TMl and WNT5B were highly expressed in OSCCs in comparison with nonnal tissues. 1n an orthotopic mouse model of OSCC, periostin-overexpressing cells metas tasized spontaneously to cervical lymph nodes and t o t he lung through their aggressive invasiveness. These findings suggest that peri ostin, IFITMl and WNT5B play important roles for invasion and of OSCC and can be prognostic markers and therapeutic t argets of OSCC.

The incidence of oral cancer varies widely worldwide. Its treatment often produces significant functiona l and cosmetic morbidity and its mortality continues to be high. Strategies for diagnosing, managing and preventing the disease must be based on an understanding of r isk factors and the pathogenesis of the disease locally. The World Health Organizat ion has documented that few countries have a comprehensive a pproach to the diagnosis , management and prevention of cancer at various anatomic sites. This presentation will review the United States’ experience with oral cancer and its strategies fo1' affecting incidence and prognosis . The greatest obs tacles are often political and economic, not scientific.