Department of Surgical, Medical, Molecular Pathology and Critical Area, University of Pisa, Pisa, Italy.
Unit of Pathological Anatomy, University Hospital of Pisa, Pisa, Italy.
Pathologica. 2023 Jun;115(3):164-171. doi: 10.32074/1591-951X-847.
Among non-small cell lung cancers (NSCLCs), sarcomatoid carcinomas account for 3%. They are rare tumours with a poor prognosis, classified into three subgroups, namely pleomorphic carcinoma, pulmonary blastoma and carcinosarcoma. In the 5th edition of WHO Classification of Thoracic Tumours more space is given to SMARC4-deficient lung cancers. Although studies on SMARCA4-deficient lung tumours are limited, a small percentage of SMARCA4 loss is present within NSCLCs. This finding is clinically relevant, as the loss of the SMARCA4 gene is associated with a worse prognosis. In our study, we analysed the presence of the main catalytic subunit of the SMARCA4 gene, the BRG1 protein, in 60 sarcomatoid lung tumours. The results of our study show that 5.3% of sarcomatoid carcinomas have BRG1-loss in tumour cells, proving that a non-negligible amount of lung sarcomatoid carcinomas are SMARCA4-deficient. These data open the debate on the necessity of including the detection of SMARCA4 within a standardised immunohistochemical panel.
在非小细胞肺癌（NSCLC）中，肉瘤样癌占 3%。它们是罕见的肿瘤，预后不良，分为三个亚组，即多形性癌、肺胚细胞瘤和癌肉瘤。在第 5 版世界卫生组织（WHO）胸部肿瘤分类中，对 SMARC4 缺失型肺癌给予了更多关注。尽管对 SMARCA4 缺失型肺肿瘤的研究有限，但在 NSCLC 中存在一小部分 SMARCA4 缺失。这一发现具有重要的临床意义，因为 SMARCA4 基因的缺失与预后不良相关。在我们的研究中，我们分析了 60 例肉瘤样肺癌中 SMARCA4 基因的主要催化亚基 BRG1 蛋白的存在情况。我们的研究结果表明，5.3%的肉瘤样癌在肿瘤细胞中存在 BRG1 缺失，证明相当数量的肺肉瘤样癌是 SMARCA4 缺失型的。这些数据引发了关于是否需要在标准化免疫组织化学面板中纳入 SMARCA4 检测的争论。
