Department of Human Pathology, Juntendo University Graduate School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Department of General Thoracic Surgery, Juntendo University School of Medicine, Bunkyo-ku, Tokyo, 113-8421, Japan.
Virchows Arch. 2020 Nov;477(5):739-742. doi: 10.1007/s00428-020-02810-y. Epub 2020 Apr 19.
Pulmonary pleomorphic adenoma (PA) is a rare salivary gland-type neoplasm, which predominantly occurs in the proximal airway. Rearrangement of the pleomorphic adenoma gene 1 (PLAG1) is the most frequent genetic event in PAs of salivary glands. However, whether pulmonary PA also harbors PLAG1 rearrangement has not been elucidated. Here, we present a case of pulmonary PA, located at the middle lobar bronchus, in a 54-year-old man. CTNNB1-PLAG1 gene fusion was identified by reverse transcription-polymerase chain reaction using formalin-fixed paraffin-embedded tissue (FFPE). Furthermore, immunohistochemical analysis revealed nuclear expression of PLAG1 in all tumor cells. To the best of our knowledge, this is the first reported case of pulmonary PA with CTNNB1-PLAG1 fusion and PLAG1 expression. Our case illustrates the possibility that pulmonary PA could be underpinned by recurrent PLAG1 translocations akin to salivary gland PA.
肺多形性腺瘤（PA）是一种罕见的唾液腺型肿瘤，主要发生在近端气道。多形性腺瘤基因 1（PLAG1）重排是唾液腺多形性腺瘤中最常见的遗传事件。然而，肺 PA 是否也存在 PLAG1 重排尚未阐明。在这里，我们报告了一例位于中叶支气管的肺 PA 病例，患者为 54 岁男性。采用福尔马林固定石蜡包埋组织（FFPE）的逆转录-聚合酶链反应（RT-PCR）检测到 CTNNB1-PLAG1 基因融合。此外，免疫组织化学分析显示所有肿瘤细胞的 PLAG1 核表达。据我们所知，这是首例报道的具有 CTNNB1-PLAG1 融合和 PLAG1 表达的肺 PA 病例。我们的病例表明，肺 PA 可能存在类似于唾液腺 PA 的复发性 PLAG1 易位。
