腮腺原发恶性肿瘤的CT表现

CT Manifestations of Primary Malignant Tumor of the Parotid Gland

目的 分析腮腺各类型原发恶性肿瘤的CT表现 ,了解其影像学特点。资料与方法 分析经手术及病理证实的腮腺原发恶性肿瘤 19例 ,包括粘液表皮样癌 8例 ,腺泡细胞癌及腺癌各 3例 ,鳞状细胞癌及恶性混合瘤各 2例 ,腺样囊性癌 1例。结果 临床有面神经受累症状者 7例 ,其中 6例肿瘤侵及深、浅二叶。 19例中 ,5例肿物呈圆形或椭圆形 ,14例呈不规则形 ;6例边缘清楚 ,13例边缘不清楚并伴有不同程度的周围结构受侵。 17例行增强扫描 ,肿瘤均有不同程度的强化 ,其中 10例明显强化。肿瘤密度均匀 2例 ,不均匀 15例 ,内部有不同形态的低密度区 ,其中 4例中央有大片低密度坏死。 9例合并有颈部淋巴结肿大。结论 面神经受累症状为腮腺恶性肿瘤的临床特点 ,如肿瘤侵及深、浅二叶时诊断更为可靠 ;肿物边缘不规则、边界不清楚、明显强化、内部密度不均匀以及颈部淋巴结肿大为腮腺原发恶性肿瘤的影像学特点。

Objective To study CT manifestations and characteristics of the primary malignant tumor of the parotid gland.Materials and Methods CT findings of 19 cases with surgically and pathologically proved primary malignant parotid tumors were analyzed. The tumors included mucoepidermoid carcinoma (n=8), acinic cell carcinoma (n=3), adenocarcinoma (n=3), squamous carcinoma (n=2), malignant mixed tumor (n=2) and adenoid cystic carcinoma (n=1).Results Clinically, 7 cases had facial nerve paralysis, in 6 of which the tumor invaded both superficial and deep lobes. Of 19 cases, the tumor was round or oval in 5, and irregular in shape in 14. Six lesions showed clear margin, while 13 had poorly defined border and infiltrated into the adjacent structures. Enhanced CT scanning was performed in 17 cases, and all lesions showed enhancement with 10 lesions being markedly enhanced. The tumor showed homogeneous density in 2 and inhomogeneous in 15 cases, of which large central necrosis was seen in 4. Enlarged cervical lymph nodes were found in 9 cases.Conclusion Irregular shape, infiltrating margin,marked enhancement with large central necrosis and enlarged cervical lymph nodes are the features of primary malignant tumor of the parotid gland. Facial nerve paralysis is the distinguishing clinical presentation, and both the superficial and deep lobes can be involved in some cases. Based on the above characteristics, the diagnosis of malignancy can be made with confidence.