A clinicopathological study was performed on 12 (6 men, 6 women; mean age, 59.3 years) patients with mucoepidermoid carcinoma of the salivary gland treated in our department between 1995 and 2010. According to the Goode histopathological grading system, 8 cases were considered as low grade and 4 cases were considered as high grade.
As for the relationship between histopathological grading and age, no significant difference was found between mean age of patients with low-grade tumors (mean age, 55.1) and that of patients with high-grade tumors (mean age, 67.5). With regard to sex, low-grade tumors were common in women, whereas high-grade tumors were common in men.
Assessment of cervical lymph node metastasis revealed that many patients with low-grade tumors were N0, and those with high-grade tumors were N1-3. In relation to clinical staging, low-grade tumors were mostly stage I, whereas high-grade tumors were mostly stage IVA. The local control rate for patients with low-grade tumors was 75.0%, which is significantly lower than the 25.0% for patients with high-grade tumors. The 5-year cause-specific survival rate for patients with high-grade tumors was 25.0%, which is significantly lower than the 87.5% for patients with low-grade tumors. The 5-year disease-free survival rate was also significantly lower in patients with high-grade tumors, with 22.0% compared to 72.9% for patients with low-grade tumors.
These results suggest that the Goode histopathological grading system could be useful for prognostic prediction of mucoepidermoid carcinoma.