浸润性黏液性肺腺癌（IMA）具有独特的放射学和病理特征。IMA被分为孤立型和肺泡型；然而，目前尚不清楚它们在生物学上是否相同。我们对2010年1月至2018年12月期间进行肺切除手术的70例IMA患者（孤立型[n = 38]和肺泡型[n = 32]）进行了单中心回顾性分析。我们比较了两种类型之间的临床和生物学特征。EGFR、KRAS、BRAF、GNAS、ERBB2、TP53、NRG1和MET等遗传变异的频率没有差异。免疫组化检测表明，在肺泡型中MUC1的表达明显更常见（5.0%对20.0%，p = 0.01），而孤立型中MUC6的弥漫阳性则更多见（39.0%对13.0%，p = 0.02）。我们进一步将孤立型分为有或无玻璃影（GGO）的类型，将肺泡型分为有或无疯狂鹅卵石样表现（CPA）的类型，并评估了他们的手术结果。孤立型中有GGO的患者和无GGO的患者，以及肺泡型中有CPA的患者和无CPA的患者的五年总生存率和无复发生存率分别为95.8%/86.6%，64.3%/70.7%，74.6%/68.9%，以及50.0%/28.6%。遗传变异没有差异，但黏液表达模式有所不同。在孤立型和肺泡型中，根据GGO和CPA的存在，手术结果也不同。这些结果表明了从孤立型到肺泡型IMA的逐步进展。© 2023版权所有，由Elsevier B.V.出版。

Invasive mucinous lung adenocarcinoma (IMA) has unique radiological findings and pathological characteristics. IMA is classified into solitary and pneumonic types; however, it is unclear whether these are biologically identical.A single-center retrospective analysis was performed for 70 IMA patients (solitary type [n = 38] and pneumonic type [n = 32]) who underwent pulmonary resection between January 2010 and December 2018. We compared clinical and biological characteristics between the two types.The frequencies of genetic alternations such as EGFR, KRAS, BRAF, GNAS, ERBB2, TP53, NRG1, and MET were not different. Immunohistochemically, expression of MUC1 was significantly more common in the pneumonic type (5.0% versus 20.0%, p = 0.01) and diffuse MUC6 positive in the solitary type (39.0% versus 13.0%, p = 0.02). We further classified solitary types into those with or without ground-glass opacity (GGO) and pneumonic types into those with or without crazy-paving appearance (CPA), and evaluated their surgical outcomes. Five-year overall survival and relapse free survival rates were 95.8%/86.6%, 64.3%/70.7%, 74.6%/68.9%, and 50.0%/28.6% in patients with solitary type with GGO, solitary type without GGO, pneumonic type without CPA, and pneumonic type with CPA, respectively.There were no differences in genetic alternations; however, mucin expression pattern was different. Surgical outcomes were different according to the presence of GGO in the solitary type and the presence of CPA in the pneumonic type. These findings suggested a stepwise progression from solitary to pneumonic IMA.Copyright © 2023. Published by Elsevier B.V.