43例肺微小脑膜瘤样结节的临床病理分析

Minute pulmonary meningothelial-like nodule:A clinicopathological analysis of 43 cases

目的:探讨肺微小脑膜瘤样结节(minute pulmonary meningothelial-like nodules,MPMN)的临床病理特征、诊断及鉴别诊断。方法:纳入2017年12月至2019年12月广州医科大学附属第一医院的43例MPMN患者,进行常规HE染色及免疫组织化学染色,总结临床病理特征。结果:在同期8034例肺切除标本中,共发现43例MPMN,男5例,女38例,男女比例1:7.6;年龄41~77(中位数60)岁。35例(81.3%)伴发肺腺癌,5例(11.6%)伴发肺非典型腺瘤样增生,3例(6.9%)伴发肺良性病变,分别为肺大泡、肺动静脉瘘、间质性肺炎。病灶直径为0.5~7.0(平均2.2)mm。大于3 mm的病变CT表现为磨玻璃样结节,而小于3 mm病灶CT表现不明显。组织学表现为上皮样细胞及短梭形细胞呈巢状、漩涡状排列,核卵圆形,核仁不明显,可见核内包涵体。细胞均弥漫表达生长抑素受体2a(somatostatin receptor-2a,SSTR2a)、波形蛋白、孕激素受体及上皮膜抗原。结论:MPMN好发于老年女性,大部分病例常伴发肺腺癌,组织形态及免疫组织化学表型与脑膜瘤相似,免疫组织化学标志物SSTR2a、波形蛋白、孕激素受体、上皮膜抗原阳性支持该诊断。

Objective:To investigate the clinicopathological characteristics,diagnosis,and differential diagnosis of minute pulmonary meningothelial-like nodules(MPMN).Methods:Forty-three cases of MPMN were collected from December 2017 to December 2019 at the First Affiliated Hospital of Guangzhou Medical University.All cases were retrospectively studied by hematoxylin and eosin(HE)staining and immunohistochemistry(IHC).The clinicopathological features were reviewed.Results:Forty-three MPMNs were identified from 8034 patients underwent pulmonary resection.There were 5 males and 38 females with a male to female ratio of 1 to 7.6.The age ranged from 41-77 years,with a mean age 60 years.There were 35 cases(81.3%)accompanied with lung adenocarcinoma,5 cases(11.6%)with atypical adenomatous hyperplasia(AAH),and 3 cases(6.9%)with benign pulmonary lesions,including pulmonary bullae,pulmonary arteriovenous fistula,and interstitial pneumonia.The diameter of lesions ranged from 0.5 to 7 mm,with an average diameter of 2.2 mm.Lesions less than 3 mm were unconspicuous on CT,whereas lesions larger than 3 mm showed ground-glass opacity on CT.Histologically,epithelioid cells and short spindle cells are arranged in a nested or whorls shape,with oval nuclei,intranuclear inclusions and unconspicuous nucleolus.Tumor cells diffusely express somatostatin receptor 2a(SSTR2a),Vimentin,PR,EMA.Conclusion:MPMN tends to occur in elderly women,and most cases are often accompanied with lung adenocarcinoma.The histomorphology and immunohistochemical phenotype are similar to meningioma.The positive expression of immunohistochemical markers SSTR2a,Vimentin,PR,EMA would support the diagnosis of MPMN.