不同病理类型肺癌脑转移的MRI影像特征研究

MRI Features of Brain Metastases of Different Pathological Types of Lung Cancer

目的分析不同病理类型肺癌脑转移的MRI影像特点,以提高对肺癌脑转移瘤影像表现的认识。方法回顾性搜集2017年10月至2018年9月首都医科大学附属北京胸科医院收治的原发性肺癌伴脑转移患者115例,收集患者的临床资料及MRI影像资料,分析脑内病灶的大小、数目、周围水肿程度、DWI序列信号变化及强化方式,并记录结果。结果本研究共人组115例,其中2例小细胞肺癌在颅内为单纯脑膜转移,无脑实质病灶;1例肺部原发灶为腺鳞癌;1例为肉瘤样癌,数据少,予以剔除。剩余111例患者,其中男性60例,女性51例;年龄39~80岁,中位年龄62岁。单发转移组45例,多发转移组66例;共检出697个病灶;两组转移瘤数目比较,差异无统计学意义(P=0.800)。再对多发脑转移组进行分析,将肺腺癌脑转移多发组及小细胞肺癌脑转移多发组分为少数(2~11个)和多数(212个)两组,两组比较差异具有统计学意义(χ2=8.211,P=0.006)。脑转移瘤大小为Ⅰ级共有42例,Ⅱ级共有60例,Ⅱ级共有9例,转移瘤大小组间比较差异无统计学意义(χ2=7.690,P=0.104)。脑转移瘤瘤周无水肿共48例,轻度水肿共43例,中度水肿共7例,重度水肿共13例,水肿程度组间比较差异具有统计学意义(χ2=34.437,P=0.000),进一步分组为无水肿组(48例)及有水肿组(63例),两组间有无水肿比较差异无统计学意义(χ2=1.306,P=0.309)。DWI序列高信号55例,DWI序列等低信号共56例,将腺癌组与鳞癌组合并为非小细胞组,小细胞肺癌组DWI高信号19例,非小细胞肺癌组DWI高信号36例,两组比较差异具有统计学意义(χ2=16.267,P=0.006)。环状强化46例,结节状强化53例,不规则强化57例,3种强化形式组间比较差异无统计学意义(χ2=21.209,P=0.171)。结论肺癌脑转移瘤的数目和DWI序列高信号与其病理类型有一定的关系,转移瘤的大小、瘤周水肿程度及强化形式与其病理类型无明显相关性。

Objective To analyze the MRI features of brain metastases of diferent pathological types of lung cancer,in order to improve the understanding of the imaging manifestations of lung cancer brain metastases.Methods 115 patients with primary lung cancer brain metastases admitted to Beijing Chest Hospital,Capital Medical University from October 2017 to September 2018 were enrolled in this retrospective study.The patients clinical data and MRI images were collected.The size,number,the degree of peritumoral edema,DWI sequence signal intensity and enhancement form of lesions in the brain were recorded and analyzed.Results 115 cases were enrolled,of which 2 cases of small cell lung cancer with meningeal metastasis and without brain parenchymal lesions,1 case of primary lung adenosquamous carcinoma,and 1 case of sarcomatoid carcinoma were removed due to few data.111 patients left were 60 males and 51 females,aged 39~80 years old,with a median age of 62 years old.There were 45 cases in the single-lesion group and 66 cases in the multiple-lesion group.A total of 697 lesions were detected.There was no significant difference in the number of metastases between the two groups.In the multiple-lesion group,the number of cases of small amount of lesions(χ2=2-11)or large amount of lesions(n≥12)was significantly different between lung adenocarcinoma group and small cell lung cancer group(χ2=8.211,P=0.006).The size of brain metastases was:42 in gradeⅠ,60 in gradeⅡ,and 9 in gradeⅡ.There was no significant difference in the size of metastases between the two groups(χ2=7.690,P=0.104).There were 48 cases of brain metastases without edema,43 cases with mild edema,7 cases with moderate edema,and 13 cases with severe edema.There was signifcant difference in the degree of edema between the two groups(χ2=34.437,P=0.000).The patients were further divided into no-edema group(n=48)and edema group(n=63),and there was no significant difference in edema between the two groups(χ2=1.306,P=0.309).There were 55 cases of DWI hyperintensity and 56 cases of isointensity/hypointensity.The adenocarcinoma group and squamous cell carcinoma were combined into non-small cell lung cancer group.There were 19 cases of DWI hyperintensity in small cell lung cancer group,and 36 cases in non-small cell lung cancer group,and the difference was statistically significant(χ2=16.267,P=0.006).There were 46 cases of ring enbancement,53 cases of nodular enhancement,and 57 cases of irregular enhancement.There was no significant difference in enhancement form between the two groups(χ2=21.209,P=0.171).Conclusion The number of brain metastases and DWI sequence signal intensity have a certain correlation with the pathological type of lung cancer.However,the size,the degree of peritumoral edema and the enhancement form have no significant correlation with the pathological type.