BACKGROUND congenital pulmonary airway malformation (CPAM) is the most frequent congenital lung disorder. CPAM type 1 is the most common subtype, typically having a cystic radiological and histological appearance. Mucinous clusters in CPAM type 1 have been identified as premalignant precursors for mucinous adenocarcinoma. These mucinous adenocarcinomas and the mucinous clusters in CPAM commonly harbor a specific KRAS mutation. CASE PRESENTATION we present a case of a 6-weeks-old girl with CPAM type 1 where evaluation after lobectomy revealed a highly unusual complex non-mucinous papillary architecture in all cystic parts, in which both mucinous clusters and non-mucinous papillary areas harbored the known KRAS mutation. CONCLUSIONS we found that a KRAS mutation thought to be premalignant in mucinous clusters only, was also present in the other cyst lining epithelial cells of this unusual non-mucinous papillary variant of CPAM type 1, warranting clinical follow-up because of uncertain malignant potential.

中文翻译：

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一例异常非黏液性CPAM 1型非黏液性乳头状瘤伴KRAS突变的病例报告。

背景技术先天性肺气道畸形（CPAM）是最常见的先天性肺部疾病。CPAM 1型是最常见的亚型，通常具有囊性放射学和组织学外观。CPAM 1型的粘液簇已被确定为粘液腺癌的恶变前兆。这些粘液腺癌和CPAM中的粘液簇通常带有特定的KRAS突变。病例介绍我们介绍了一个6周大的CPAM 1型女孩，在肺叶切除术后的评估中发现，在所有囊性部位都有非常不寻常的复杂的非粘液性乳头状结构，其中粘液性簇和非粘液性乳头状区域都具有已知的KRAS突变。结论我们发现，仅在粘液簇中，KRAS突变被认为是癌变前的，