Objective: To investigate the clinicopathological features and genetic characteristics of congenital cystic adenomatoid malformation (CCAM) of lung and CCAM associated lung cancer in adults. Methods: A total of 13 cases of CCAM of lung in adults, diagnosed from June 2015 to May 2023, were collected from the Department of Pathology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, China. Their histopathological features were correlated with probable development into lung cancer. Next-generation sequencing was performed on the benign and malignant areas of all cases. Results: The pathological classification of all cases were of CCAM of lung type 1. There were 4 male and 9 female cases, age ranged from 18 to 65 years, with a mean age of 41 years. Six cases were accompanied by lung cancer, all of them were mucinous adenocarcinoma. Next-generation sequencing showed no gene mutation in 2 of the 13 cases; KRAS mutations in exon 2 were detected in 7 cases, in which there were 6 cases complicated with lung mucinous adenocarcinoma and no matter in the malignant or benign regions, the same case exhibited the same mutation sites in KRAS gene. Conclusions: CCAM of the lung is a congenital disease, and in adults, type 1 is most commonly found in the pathological classification, and it is often accompanied by cancer. Gene mutations are frequently detected in CCAM of the lung, KRAS being the most recurrent mutation which may play an important role in the carcinogenesis.
目的： 探讨成人肺先天性囊性腺瘤样畸形（congenital cystic adenomatoid malformation，CCAM）及其伴发肺癌间临床病理学特征的异同并探索其基因特征性改变。 方法： 收集同济大学附属上海市肺科医院病理科2015年6月至2023年5月诊断的13例成人肺CCAM病例，分析其临床病理特点，对其病理分型、组织学特点以及与肺癌发生的相关性进行讨论，并对这13例病例的良性及癌变区域分别进行二代测序。 结果： 13例成人肺CCAM的病理分型均为1型，男性4例，女性9例，年龄18~65岁，平均年龄41岁，其中6例伴发肺癌且均为黏液腺癌。发生癌变的病例囊壁内可见黏液腺上皮增生，周围可见黏液腺癌。二代测序结果显示，13例病例中仅2例未检测到基因突变，在7例具有KRAS基因第2号外显子突变的病例中6例伴发黏液腺癌，且同一病例中无论是癌变区域还是良性区域均具有相同位点的KRAS基因突变。 结论： 成人肺CCAM是一种先天性疾病，其中成人患者最常见的病理分型为1型，且常可伴发黏液腺癌，基因突变较为常见，其中KRAS基因突变最为常见且与癌变高度相关，其发生在黏液腺上皮增生/黏液腺癌之前，可能是驱动癌变的重要因素。.