Background: Mucoepidermoid carcinoma (MEC) can have a variety of clinical outcomes, but prognosis seems to be related to the tumor grade. The system proposed by Auclair and Goode is useful, and our data lend further support to its application and validity in clinical practice.
Methods: We have clinicopathologically reviewed 108 cases of MEC originating in major (MASG) and minor (MISG) salivary glands that were treated at the National Cancer Institute of Milan between 1975 and 1995. Following the methods of Auclair and Goode, a quantitative grading system was used. The relationships between clinical and pathologic characteristics and survival rate were investigated.
Results: Twenty-six (44%) cases located in MASG and 19 (39%) cases in MISG were categorized as high-grade tumors. In patients with MASG tumors, the 5-year disease-free survival rate was 22.5% when the tumor was high grade and 97.0% if the tumor was low grade (P <.0001). For patients with a tumor of the MISG, the percentages were 35.3% for high-grade and 80.0% for low-grade tumors (P =.0066).
Conclusions: Our study confirms that in MEC, tumor grade, subdividing cases into low and high grade by using the criteria delineated by Auclair and Goode, correlates well with prognosis.