Expression And Significance Of PTEN,Survivin,Ki-67 In Oncocytic Carcinoma Of Salivary Gland

Oncocytic carcinoma of salivary gland is a rare tumor whichaccounts for 0.05% of all salivary gland tumors. The purpose of thisstudy was investigated clinico-pathologic characteristics of oncocyticcarcinoma of Salivary gland and examined the expression of PTEN,survivin,ki-67 by immunochemical method in 9 normal Salivarygland, 9 benign salivary gland tumor(4 adenolymphoma and 5oncocytoma), 9 oncocytic carcicnoma in order to detect the expressionof PTEN,survivin,ki-67 in these tumors and explore the significance ofthese factors in oncocytic carcinoma.Most cases of oncocytic carcinoma occurred in parotid gland.Patients' mean age is 56.4 years. The ratio of male to female was1:1.2.The mean size of the tumors was 3.2cm.the clinical feature is apainless, nondescript mass in the salivary gland. Facial nerve involvement may cause pain, paresis or neuropathy. Microscopically, thesheet, island and nest of tumor cells were composed of large, round topolyhedral cell with fine, granular, eosinphilic cytoplasm and central,round nuclei. In some tumors there was duct-like structure of variablecaliber. They were unencapsulated and often invade muscle, lymphaticsand nerves. They are characterized cytologically by cellular atypia andpleomorphism. The main treatment of this carcinoma was surgery.PTEN positive stain was found in 100% of the normal salivarygland, 100% of the benign oncocytic tumors, 55.6% of oncocyticcarcinoma, respectively. The expression of PTEN in oncocyticcarcinoma significantly decreased (P＜0.05). The overexpression ofsurvivin were identified in 9 cases (100%) of the benign salivary tumors,and 9 cases(100%) of the oncocytic carcinoma while no positivitystaining were detected in normal salivary gland. The expression ofsurvivin in the benign and malignant oncocytic tumors increasedsignificantly (P＜0.05). Ki-67LI in the normal salivary gland,benignoncocytic tumors and oncocytic carcinoma was 0, 4.24±1.67 and9.23±1.79, respectively. Ki-67LI of oncocytic carcinoma wassignificantly higher than that in benign oncocytic tumors (P＜0.05). Conclusively, the loss of PTEN expression might be involved inthe carcinogenesis of oncocytic carcinoma. The overexpression ofsurvivin might play an important role in the development of oncocytictumor and carcinoma of salivary gland. Ki-67LI of oncocytic carcinomawas significantly higher than that in oncocytoma, Ki-67 immunostainingmay be useful in distinguishing benign oncocytoma from malignantoncocytoma.