涎腺腺样囊性癌的CT、MRI表现及病理对照研究

目的分析涎腺腺样囊性癌(adenoid cystic carcinoma,ACC)的CT与MRI表现及病理基础。方法回顾性分析经病理证实的22例ACC的CT与MRI表现,并与病理结果进行对照研究。结果 22例患者中,发生于腮腺7例、上颌窦3例、舌3例、下颌下腺3例、鼻腔2例、筛窦2例、腭1例、气管1例,形态较规则14例,不规则形8例;直径10mm~53mm,平均约29mm;14例行CT检查,平扫5例为均匀等、稍低密度,9例为不均匀等低密度,增强扫描4例均匀强化,10例不均匀强化,内见小斑片状、筛孔状未强化区。8例行MRI检查,T1WI为均匀或不均匀等、低信号,T2WI主要为混杂高信号,6例内见小斑片状、筛孔状更高信号区,增强扫描2例均匀强化,6例不均匀强化,内见小斑片状、筛孔状未强化区。周围结构侵犯9例,淋巴结转移3例,远处转移1例。结论ACC的病理基础决定其影像表现,CT及MRI增强扫描ACC易出现小斑片状、筛孔状未强化区域,并且CT与MRI检查对判断肿瘤侵犯范围起重要作用。

The CT and MRI Findings and Pathological Basis of Adenoid Cystic Carcinoma of the Salivary Glands

Objective To investigate the CT and MRI findings and pathological basis of adenoid cystic carcinoma(ACC) of the salivary glands.Methods The CT or MRI findings of 22 ACC of the salivary glands confirmed by pathology were retrospectively analyzed, and were compared with pathological results.Results The tumors occurred in parotid gland (7 cases), maxillary sinus (3cases), sublingual (3cases), submandibular gland (3 cases), nasal sinus (2cases), palatum(2cases), trachea (1cases); 14 cases were in regular shape, 8 cases were in irregular shape. The tumor diameter ranged from 10mm to 53mm with a mean value of 29mm. Fourteen cases underwent CT examination, isodensity or low density were revealed on plain CT scan, 5 cases were with homogenous density and 9 cases were with heterogeneous density. On contrast-enhanced CT, homogenous enhancement were observed in 4 cases, heterogeneous enhancement with small patchy or cribriform non-enhanced region were observed in 10 cases. Eight cases underwent MRI examination, T1WI showed iso-or hypointense, T2WI showed heterogeneous hyperintense, small patchy or cribriform region of obvious hyperintense were observed in 6 cases. On contrast-enhanced MRI, homogenous enhancement were observed in 2 cases, heterogeneous enhancement with small patchy or cribriform non-enhanced region were observed in 6 cases. Five cases were found with adjacent structures invasion. Three cases were found with lymph node metastasis, 1 case were found with distant metastases. Conclusion The pathology of ACC determines the characteristic of imaging findings, small patchy or cribriform non-enhanced region is always revealed on CT and MRI scans. CT and MRI play an important role in assessing extent of tumor invasion.