Sekhawat Vivek, van der Linde Martijn, Routledge Tom, Santis George, Nonaka Daisuke
Department of Cellular Pathology, Guy's & St Thomas' NHS Foundation Trust, London, UK.
Clinical Genomics, The Royal Marsden NHS Foundation Trust, London, UK.
Int J Surg Pathol. 2025 Apr;33(2):462-465. doi: 10.1177/10668969241261541. Epub 2024 Jul 21.
Metaplastic thymoma is a rare thymic neoplasm that has generally been considered to follow a benign to indolent clinical course; however, 3 metaplastic thymomas with high-grade malignant transformation to sarcomatoid carcinoma have been reported. In recent years, both conventional metaplastic thymomas and this subset showing malignant transformation have been associated with recurrent fusions. We report a metaplastic thymoma showing transformation to squamous cell carcinoma, that to our knowledge is the fourth reported in the literature with transition to overtly malignant features and the first showing pure carcinomatous transformation, and in which fusion was demonstrated via next generation sequencing.
化生性胸腺瘤是一种罕见的胸腺肿瘤，通常被认为临床病程呈良性至惰性；然而，已有3例化生性胸腺瘤发生高级别恶性转化为肉瘤样癌的报道。近年来，传统化生性胸腺瘤以及显示恶性转化的这一亚组均与复发性融合相关。我们报告了1例发生转化为鳞状细胞癌的化生性胸腺瘤，据我们所知，这是文献中报道的第4例向明显恶性特征转变的病例，也是第1例显示单纯癌性转化的病例，并且通过二代测序证实了其中存在融合。
