腮腺多形性腺瘤的CT表现

CT Manifestations of Parotid Pleomorphic Adenoma

目的 分析腮腺多形性腺瘤的CT表现 ,了解其影像特点。资料与方法 分析经手术及病理证实的腮腺多形性腺瘤 18例 ,包括原发良性多形性腺瘤 12例 ,复发 4例 (其中 1例与原发多形性腺瘤重叠 ) ,恶性多形性腺瘤 3例。结果 12例良性多形性腺瘤中 ,8例呈圆形或椭圆形 ,4例呈多结节分叶形 ,12例肿物均边缘清楚 ,但密度不均匀 ,内部有不同形态的低密度区。 4例复发肿瘤均为多发 ,呈多结节、多环形各 2例。 3例恶性混合瘤肿物轮廓均不规则 ,边界不清楚 ,密度不均匀 ,均可见大片坏死区。结论 边界清楚 ,肿物内部有不同形态的低密度区为腮腺良性多形性腺瘤的CT特点。肿瘤的边界不清楚 ,有大片坏死区应考虑恶性多形性腺瘤的可能性 ,长期腮腺肿物的病史 。

Objective To study CT characteristics of parotid pleomorphic adenoma.Materials and Methods CT findings of 18 cases with pathologically proved parotid pleomorphic adenoma were reviewed. The lesions included benign pleomorphic adenoma (n=12), benign recurrent pleomorphic adenoma (n=4) and malignant pleomorphic adenoma (n=3).Results Of 12 benign pleomorphic adenomas, 8 were round or ellipse in shape, the other 4 were multi nodular and lobulated. All the 12 lesions were well defined and inhomogeneous in density with multiple low attenuation areas within the tumor. All the 4 recurrent tumors showed multiple lesions, presenting as multi nodules (n=2) or a multi ring like mass (n=2). The three malignant pleomorphic adenomas were inhomogeneous in density with ill defined margin and large central necrotic area.Conclusion Benign pleomorphic adenoma displays as a mass with well defined margin and central low attenuation area. Malignant pleomorphic adenoma should be considered when the lesion is ill defined with large central necrotic area, especially in the patients with a long course of parotid mass which quickly enlarges recently.