腮腺少见肿瘤的影像学特点分析

Imaging characteristics of rare tumor of parotid gland

目的探讨腮腺少见肿瘤的影像学特点。方法回顾性分析13例经手术病理证实腮腺少见肿瘤(淋巴上皮癌4例,肌上皮瘤3例,淋巴瘤及转移瘤各2例,恶性黑色素瘤及肌上皮癌各1例)的CT、MRI影像学表现。结果均为腮腺单侧发病,其中左侧9例,右侧6例。淋巴上皮癌位于腮腺浅叶,可累及深叶,以单发为主(3/4);沿腮腺浅叶铸形生长(3/4)可能具有一定特点;密度和信号均匀,增强轻、中度均匀强化。肌上皮瘤均为单发,位于腮腺浅叶,呈椭圆形,边缘清晰锐利,密度和信号均匀或不均匀,显著强化(2/3)可能具有提示作用。淋巴瘤具有一定特点,常表现为多发类圆形肿块(2/2),边缘光整,密度均匀,增强后中度强化,常伴颈部淋巴结肿大。恶性黑色素瘤MRI具有一定特点:T1WI呈多发结节状高信号,T2WI呈低信号;CT及MRI增强不具特点。肌上皮癌与腮腺常见恶性肿瘤相仿。转移瘤表现与原发肿瘤密切相关。结论腮腺上述少见肿瘤部分具有一定影像学特点,有助于鉴别诊断,确诊仍依靠组织病理学和免疫组化。

Objective To study the imaging characteristics of rare tumor of parotid gland .Methods CT ,MRI imaging findings of 13 cases of rare tumor （4 cases of lymphoepithelial carcinoma ,3 cases of myoepithelioma ,2 cases of lymphoma and metastatic tumors in each 1 case of malignant melanoma and myoepithelial carcinoma in each in the parotid gland） con‐firmed by operation and pathology were retrospectively analysed .Results The lesions were located in the unilateral parot‐id gland ,in the left side （n=8） ,in the right side （n=5） .Lymphoepithelial carcinomas were located in the superficial lobe of parotid gland ,which may violate the deep lobe ,majority of single lesion （3/4） .Casting growth （3/4） along the parotid gland may have certain feature：homogeneous density and signal ,light to moderate enhancement after enhance‐mend .Myoepitheliomas were solitary and located in the superficial lobe of parotid gland ,with oval and sharp edge ,homo‐geneous or inhomogeneous density and signal .Marked enhancement （2/3） may help diagnosis .Lymphoma had certain characteristics ,which manifested multiple round mass （2/2） ,smooth edges and homogeneous density ,moderate enhance‐ment ,frequently accompanied by cervical lymphadenopathy .Malignant melanoma had certain characteristics on MRI：mul‐tiple high signal nodules on T1WI ,low signal on T2WI ,no characteristics on enhanced CT and MRI .Myoepithelial carci‐noma had not different with common malignant tumor of parotid gland .The findings of the metastasis tumor of parotid gland were closely related to primary tumor .Conclusion The part of the above‐mentioned rare tumors of parotid gland have certain imaging characteristics ,which are helpful for differential diagnosis .Final diagnosis still depends on histopa‐thology and immunohistochemistry .