原发性肺黏液腺癌的MSCT表现

MSCT features of primary pulmonary mucinous adenocarcinoma

目的:探讨原发性肺黏液腺癌(PPMA)的MSCT表现,提高医师对该病的认识。方法:回顾性分析经术后病理证实的30例PPMA患者,按病灶平均直径将其分为A组(直径1~5 cm)16例和B组(直径>5 cm)14例。2组均行CT平扫与增强扫描,分析并比较2组病灶位置、内部特征、瘤周征象及CT值。结果:30例PPMA患者中,26例表现为结节或肿块,4例表现为大片状实变影。30例病灶平扫平均CT值(30.3±9.1)HU,同层面肌肉平扫平均CT值(52.4±2.4)HU,差异有统计学意义(t=9.334,P<0.05);平扫平均CT值A组(34.0±6.7)HU,B组(24.3±9.8)HU,2组差异有统计学意义(t=2.365,P=0.033);强化幅度A组(19.3±6.8)HU,B组(14.6±3.5)HU,2组差异有统计学意义(t=2.121,P=0.045)。A组深分叶、毛刺征的发生率(56.2%、43.8%)均高于B组(14.3%、7.1%),差异均有统计学意义(均P<0.05);B组血管造影征的发生率(85.7%)高于A组(43.8%),差异有统计学意义(P<0.05)。结论:PPMA是肺癌少见类型,CT上多表现为肺内孤立结节或肿块,少数呈类肺炎样改变,病灶平扫CT值常低于同层面肌肉CT值;病灶直径≤5 cm时,深分叶征及毛刺征发生率较高,而病灶直径>5 cm时,常伴空气支气管征及CT血管造影征,其平扫及增强扫描CT值有减低趋势,上述征象有助于诊断。

Objective:To investigate the MSCT features of primary pulmonary mucinous adenocarcinoma(PPMA)and improve understanding of the disease.Methods:This was a retrospective analysis of 30 patients of PPMA confirmed by postoperative pathology.According to the average diameter of lesions,30 cases were divided into two groups,16 cases in group A(5≥d≥1 cm)and 14 cases in group B(d>5 cm).All patients underwent CT plain scan and enhanced scan.The location,internal features,peripheral change and CT values of the two groups were analyzed and compared.Results:The lesions of 26 cases showed nodules or masses,and the lesions of 4 cases showed a patchy consolidation.In 30 measurable lesions,the average CT value of plain scan was(30.3±9.1)HU,the average CT value of muscle in the same plane was(52.4±2.4)HU,the difference was statistically significant(t=9.334,P<0.05).The average CT value of plain scan in group A and group B was(34.0±6.7)HU and(24.3±9.8)HU,respectively,the difference was statistically significant(t=2.365,P=0.033).The enhancement amplitude in group A and group B was(19.3±6.8)HU and(14.6±3.5)HU,respectively,the difference was statistically significant(t=2.121,P=0.045).The incidence of deep lobulation and spiculation signs in group A(56.3%,43.8%)was higher than that in group B(14.3%,7.1%),and the differences were statistically significant(both P<0.05).The incidence of angiographic signs in group B(85.7%)was higher than that in group A(43.8%),and the difference was statistically significant(P<0.05).Conclusions:PPMA is a rare type of lung cancer,most of which are solitary nodules or masses in the lung on CT,and a few are pneumonia-like changes.The CT value of lesion on plain scan is often lower than that of muscles on the same plane.When the lesion diameter is smaller than 5 cm,the incidence of deep lobulation signs and spiculation signs becomes higher.However,when the lesion diameter is larger than 5 cm,PPMA is often accompanied by air bronchial signs and CT angiography signs,and the value of plain scans and enhanced CT tends to decrease,which is helpful for the diagnosis of PPMA.