41例脑先行肺癌脑转移瘤的影像学分析

The Imaging Characteristics of 41 cases of "Cerebral Preceding" metastatic cancers from lungs

目的总结脑先行肺癌脑部转移瘤的CT及MRI影像学表现,提高对脑先行肺癌脑部转移病灶的认识。方法对41例诊断明确的以脑部转移瘤为首发症状肺癌患者的颅脑CT或MRI的影像学资料进行回顾分析。结果所有41例患者均以脑部转移瘤的症状而首诊就诊。脑部转移瘤为单发者14例(34%),多发者27例(66%);CT增强扫描比平扫多发现约10%的阳性病例,多发现病灶个数约20%;MRI增强扫描比平扫多发现病灶个数约16%;4例病例先后进行CT及MRI检查,MRI未能增加病灶检出数目。最常见的转移部位为顶叶(43%)、额叶(22%)、颞叶(18%)及皮层下(75%);无瘤周水肿者占22%、瘤周水肿明显者占49%;表现结节样均匀强化者占27%、环形强化者67%。其他表现为囊性肿块6例,病灶内出血8例。结论脑先行肺癌脑部转移瘤的表现多种多样,约1/3的患者的脑转移病灶表现不典型;患者就诊时临床大多因脑先行所致中枢神经系统症状初诊为脑血管意外及癫痫。对于此类患者,当行颅脑CT或MRI检查时,要注意进行增强扫描;当发现脑部占位病,一定要考虑到脑先行肺癌的可能,从而进一步行胸部平片或CT检查。

Objective To study the CT and MRI imaging manifestations of ＂cerebral preceding metastases＂ and enhance the cognition to the lesions of ＂Cerebral Preceding＂ metastatic cancers from lungs. Methods The cerebral CT or MRI imaging data of 41 patients with ＂cerebral metastases preceding＂ from lung cancer were analyzed retrospectively. All of the primary lung cancers were histologically diagnosed bybiopsy via percutaneous intrathoracic needle aspiration or fibrobronchoscope. Results All the 41 patients were diagnosed with the initial symptoms of brain metastases.The cerebral lesions showed solitary lesions in 14 cases （34%）, multiple lesions in 27 cases （66%）; It could show more about 10% of the cases and more about 20% of the number of lesions on enhanced CT scan than on plain CT scan; And it could show more about 16% of the number lesions on enhanced MRI scan than on the plain scan; 4 cases had been checked by both CT and MRI, MRI was failed to check out more lesions than that on CT. The most common metastatic sites were parietal （43%）, frontal （22%）, temporal lobe （18%） of the brain, and in subcortical （75%） brain. The lesions without peripheral edema accounted for 22%, with obvious peripheral edema accounted for 49 %; with nodular homogeneous enhancement in 27%, with ring-shaped enhancement in 67%. It showed cystic mass in 6 cases, and 8 cases showed bleeding in the lesions. Conclusion The manifestations of ＂Cerebral Preceding＂ metastatic cancers from lungs are varied, imaging characteristics of brain metastases are atypical in about 1/3 of patients; and most patients are initial diag- nosed as cerebrovascular accident or epilepsy due to the clinlcal symptom of central nervous system. For such patients, it is very important to perform the enhanced CT or MRI scans, and when the cerebral lesion is found, the lungs should be the first valuation in case of a cerebral metastasis with an unknown primary and the chest plain radiographs and/or CT should be performed for detecting of the possibility of ＂Cerebral Preceding＂ lung cancers. [