BACKGROUND: Primary surgery is the appropriate treatment for most pleomorphic adenomas of the salivary glands. However, no reliable criteria have been established to predict tumors with aggressive features. METHODS: In 44 patients treated for salivary pleomorphic adenoma, clinicopathologic features and flow cytometric findings were recorded. S-phase fractions were classified as low (0%-1%), intermediate (1.1%-5%), and high (>5%). The relationship between clinicopathologic parameters and flow cytometric DNA analysis was assessed with the Pearson's correlation coefficient. RESULTS: The mean tumor size was 24.4 mm. Microscopically, myxoid structures predominated in 61.4% of cases. Only five specimens showed high S-phase fractions. All samples were DNA diploid (mean coefficient of variation 3.2%). S-phase fraction and tumor size correlated significantly (r = 0.73, P = 0.003). Two patients with recurrent tumors had high S-phase fractions both on the first resected specimens and at the time of the second operation. CONCLUSIONS: The S-phase fraction may be a valuable predictor of aggressive behavior in salivary pleomorphic adenomas. High S-phase fractions were associated with higher tumor size and a greater tendency to recur. Copyright 1999 John Wiley & Sons, Inc. Head Neck 21: 652-656, 1999.
BACKGROUND: Primary surgery is the appropriate treatment for most pleomorphic adenomas of the salivary glands. However, no reliable criteria have been established to predict tumors with aggressive features. METHODS: In 44 patients treated for salivary pleomorphic adenoma, clinicopathologic features and flow cytometric findings were recorded. S-phase fractions were classified as low (0%-1%), intermediate (1.1%-5%), and high (>5%). The relationship between clinicopathologic parameters and flow cytometric DNA analysis was assessed with the Pearson's correlation coefficient. RESULTS: The mean tumor size was 24.4 mm. Microscopically, myxoid structures predominated in 61.4% of cases. Only five specimens showed high S-phase fractions. All samples were DNA diploid (mean coefficient of variation 3.2%). S-phase fraction and tumor size correlated significantly (r = 0.73, P = 0.003). Two patients with recurrent tumors had high S-phase fractions both on the first resected specimens and at the time of the second operation. CONCLUSIONS: The S-phase fraction may be a valuable predictor of aggressive behavior in salivary pleomorphic adenomas. High S-phase fractions were associated with higher tumor size and a greater tendency to recur. Copyright 1999 John Wiley & Sons, Inc. Head Neck 21: 652-656, 1999.