Study Of Correlative Clinicopathologic Factors Influencing The Prognosis Of Mucoepidermold Carcinoma In Salivary Glands

Mucoepidermoid carcinoma (MEC), constituting approximately 30% of salivary gland carcinomas, is the most frequently encountered malignant salivary neoplasm. Most MECs are low grade, and patients have a favorable outcome after initial surgical treatment. A few MECs present with high grade histologic appearance and often develop recurrence and metastasis after surgical treatment, even lead to the death of patients.Objective: The paraffin slides and clinical documents of 98 patients with MECs of salivary glands were reviewed. All patients underwent curative therapy in Department of Oral and Maxillofacial Surgery, College of Stomatology, Fourth Military Medical University. The correlative clinicopathologic factors influencing the prognosis were analyzed and the results were hoped to be helpful for clinical practice.Material and Methods: 1. Ninety-eight patients were involved in the study, and clinicopathologic parameters (e.g. age, gender, primary sites, presenting symptoms, clicical stage, degree of differentiation, lymphocyte infiltrating, pathologic nodal status, tumor cell mitotic rate, necrosis, etc.) were evaluated using univariate and rnultivariate analysis to determine the effects on survival of patients. The results were compared using Log rank test and considered significantly positive for a P value of <0.05 and survival rate were obtained by the Kaplan-Meier method. 2. Fifty-nine patients with MEC who underwent initial surgical therapy and follow-up more than five years were reviewed to evaluate the clinicopathologic factors influencing postoperative recurrence and metastasis. The Logistic regression model was used to determine the main effective factors. Statistical analysis was performed using the SPSS 10.0 software.Results: 1. The overall survival rates of the studied patients were 93.78%, 87.22%,-3-85.24% and 85.24% respectively at 3, 5, 10 and 15 years. Clinicopathologic factors correlated with decreased in survival rates were advanced clinical stage (stage III and stage IV), older patient age( =60), necrotic presentation and metastatic presentation after operation. 2. Both of the recurrent and metastatic rate were 23.73%. Metastasis were more preferentially occurred in cervical regional lymph node. The rate of distant organ metastasis were only 2.14%. The recurrence easily occur in the patients with the tumors that is of advancing clinical stage, bone involvment, abundant lymphocyte infiltrating and high mitotic rate (=4). The metastasis easily occur in the patients with the tumors that is of poor differentiation, HI type of tumor border and local recurrence.Conclusions: 1. The important cinicopathologic factors including clinical stage, patient age and necrosis influence the survival rate of the patients with MEC in salivary glands. 2. Clinical stage, lymphocyte infiltrating patterns, mitotic rate and bone involvement are the main factors associated with the recurrence. Degree of differentiation, patterns of tumor border and local recurrence are the important factors influencing the postoperative metastasis. 3. It is important to improve the survival time of the patients with MEC in salivary glands that surgical therapy is performed at early stage. The surgical margins of involved bone must be noticed in the course of resection. Elective neck dissection must be performed in patients with poor differentiation MEC. Selected patients accept the combinative therapy after surgical treatment according to the Clinicopathologic parameters. 4. The patients must be followed-up regularly in five-year period after operation and accept the operation in time once recurrence.