Differential diagnosis of parotid masses by dynamic contrast-enhanced MR

Objective: To investigate the value of dynamic contrast-enhanced (DCE) MRI at 3.0 T in differential diagnosis of parotid masses. Methods: DCE-MRI was performed on 62 patients with 87 pathologically confirmed parotid masses. The quantitative parameters including K^trans, K_ep, and Ve of parotid masses were compared using Kruskal-Wallis H and Mann-Whitney U tests. The sensitivities and specificities for differentiating benign and malignant tumors at various cutoff values were calculated. Results: The differences among the three parameters for malignant tumors, Warthin tumors, pleomorphic adenomas and other benign tumors were statistically significant (χ² = 8.627, 45.409, 50.938, P < 0.01). The K_ep values of malignant tumors were significantly lower than those of Warthin tumors. The K^trans and K_ep values of malignant tumors were significantly higher than those of pleomorphic adenomas, The and values of Warthin tumors were significantly higher than those of pleomorphic adenomas. At cutoff value of 0.98 min^-1 and V_e of 0.351, the sensitivity and specificity of differential diagnosis between malignant and Warthin tumors were 75.0% and 76.27%, respectively. The cutoff value of 0.28 min^-1 was 67.85% sensitive and 61.53% specific in differentiating malignancy from pleomorphic adenomas. At the K_ep cutoff value of 0.69 min^-1, the sensitivity and specificity of differential diagnosis between malignancy and pleomorphic adenomas were 67.85% and 73.07%, respectively. Conclusion: Quantitative parametric analysis of DCE-MRI contributes to pre-operative differential diagnostic of benign and malignant parotid tumors. (authors)