近端型与远端型细支气管腺瘤临床病理特征的比较分析（附4例）

目的:探讨细支气管腺瘤（BA）的两型临床病理特征、诊断及鉴别诊断。 方法:收集该院2018年3月至2021年4月收治的4例BA病例，分析其临床资料、影像学检查、组织病理学特征、免疫组织化学表型及鉴别诊断等。 结果:患者中男性2例，女性2例，1例有吸烟史，2例无临床症状。影像学表现为磨玻璃或边界清楚的结节。大体示灰白、灰褐色的实性结节或局灶见微囊，多数界清但无包膜，最大径0.6~1.2 cm。例1、例2肿瘤镜下显示双层乳头结构，内层富于纤毛细胞和黏液细胞，表达CK7、Napsin-A、CEA、MUC5AC，弱表达TTF-1，外层是基底细胞，表达p40、CK5/6，诊断为近端型BA。例3、例4肿瘤镜下显示双层腺腔型结构，内层由Ⅱ型肺泡上皮和Clara细胞构成，缺乏纤毛和黏液细胞，表达CK7、Napsin-A、TTF-1、弱表达CEA、MUC5AC，外层由基底细胞构成，表达p40、CK5/6，诊断为远端型BA。 结论:细支气管腺瘤是一种具有双层结构的良性肿瘤，影像学检查及快速冷冻切片中易误诊为恶性。根据黏液细胞及纤毛细胞所占腔面细胞的比例，将细支气管腺瘤分为近端型和远端型。

Comparative analysis of clinicopathological features of bronchiolar adenoma with proximal type and distal type (4 cases)

Objective:To investigate the clinicopathological features,diagnosis and differential diagnosis of two types of bronchiolar adenoma. Methods:Four cases of BA treated in our hospital from March 2018 to April 2021 were collected,and their clinical data,imaging examination,histopathological features,immunohistochemical phenotype and differential diagnosis were analyzed.Results:Among the patients,there were 2 males and 2 females,1 had a history of smoking and 2 had no clinical symptoms.The imaging findings were ground glass or well-defined nodules.Generally,there are gray and gray brown solid nodules or local microcapsules,most of which are clear with no capsule,and the maximum diameter is 0.6~1.2 cm.Cases 1 and 2 showed double-layer papillary structure under microscope.The inner layer was rich in ciliated cells and mucus cells,expressing CK7,Napsin-A,CEA and MUC5AC,weakly expressing TTF-1,and the outer layer was basal cells,expressing p40 and CK5/6.It was diagnosed as proximal BA.Cases 3 and 4 showed double-layer glandular cavity structure under microscope.The inner layer was composed of type II alveolar epithelium and Clara cells,lacking cilia and mucus cells,expressing CK7,Napsin-A,TTF-1,weak CEA and MUC5AC,and the outer layer was composed of basal cells,expressing p40 and CK5/6.It was diagnosed as distal BA.Conclusion:Bronchiolar adenoma (BA) is a benign tumor with double-layer structure.It is easy to be misdiagnosed as malignant in imaging examination and rapid frozen section.According to the proportion of mucous cells and ciliated cells in luminal cells,bronchiolar adenomas were divided into proximal and distal types.