Objective: To observe the clinicopathological features of bronchiolar adenoma (BA) and mixed squamous cell and glandular papilloma (MSGP). The relationship between them was also analyzed. Methods: Clinical data of eight patients with BA and four patients with MSGP diagnosed in China-Japan Friendship Hospital were collected from January 2018 to January 2020. Hematoxylin-eosin staining and immunohistochemical staining (EnVision method) were used to compare their histopathological characteristics. The hotspots regions of cancer-associated driver genes in lung cancer, using real-time quantitative PCR, were detected in all the cases and the literatures were reviewed. Results: The clinical and imaging manifestations of BA and MSGP were analogous. Histologically they had a two-layer structure including bronchial or bronchiolar-type epithelium and a continuous layer of basal cells,similar to bronchial/bronchiole mucosae. P16 protein was highly expressed in 7/8 of BA and 1/4 of MSGP. Mutations of cancer-associated genes were detected in 4/8 of BA, but none in MSGP. Conclusions: BA and MSGP, derived from different parts of the respiratory tract in the lungs, are rare and benign. Their morphological features overlapped with each other, and some cases are accompanied by genetic changes. It is necessary to pay attention to the differential diagnosis between them and lung adenocarcinoma, especially during the intraoperative diagnosis; and be alert to the potentially malignant components in the tumor or combined cancers.
目的： 观察肺细支气管腺瘤（bronchiolar adenoma，BA）与混合性鳞状细胞和腺性乳头状瘤（mixed squamous cell and glandular papilloma，MSGP）临床病理特征，浅析两者关系。 方法： 收集2018年1月至2020年1月中日友好医院8例BA及4例MSGP临床资料，采用HE染色及免疫组织化学EnVision法对比肿瘤病理形态特征，利用即时荧光定量PCR方法检测肺癌常见驱动基因改变情况，并复习相关文献。 结果： BA与MSGP临床及影像表现类似，它们均具有连续基底细胞和上皮细胞所构成的双层结构特征，形态上模拟支气管/细支气管黏膜上皮组织学分化。7/8 BA及1/4 MSGP呈p16蛋白高表达。4/8 BA检测到肺癌常见驱动基因突变，MSGP均未见驱动基因改变。 结论： BA与MSGP病例罕见，均为来源于肺内呼吸道不同部位支气管/细支气管黏膜上皮的良性肿瘤，形态学特征相互重叠，部分病例伴有基因改变。尤其在术中冷冻切片病理诊断时，要重视它们与肺腺癌的鉴别诊断，并警惕肿瘤内的恶性病变或合并恶性肿瘤的可能。.