Shao Mumin, Zhang Lu, Li Xia, Bi Jiaxin, Jiang Xu, Yu Xuewen, Liang Yingying, Xu Hua, Meng Gang, Gong Xiyu
Department of Pathology, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
Department of Pathology, Fourth Clinical Medical College of Guangzhou University of Traditional Chinese Medicine, Shenzhen, Guangdong, China.
J Clin Pathol. 2025 May 25;78(6):390-398. doi: 10.1136/jcp-2024-209489.
Phyllodes tumours (PTs) are relatively common fibroepithelial tumours comprising epithelial and stromal component. Usually, PTs show a spindle cell morphology with a fibroblast phenotype, while some tumour cells exhibit epithelioid morphological features and sarcomatoid transformation. However, the molecular characteristics of this morphology subset remain unclear. This study aimed to summarise the clinicopathological, morphological and molecular characteristics of seven cases of PT with epithelioid features.
Morphological and clinicopathological characteristics were observed and retrieved. Immunohistochemistry, immunofluorescence and electron microscope were performed on seven cases of epithelioid PT to explore immunophenotypic and ultrastructural characteristics. Transcriptomic and proteomic analyses were conducted to compare differentially expressed genes and proteins between epithelioid PT and classical PT.
Patients with epithelioid PT exhibit a high recurrence rate (42.8%). Morphologically, in addition to having epithelioid cytological features, neoplastic stromal cells exhibit moderate to marked atypia and often exhibit sarcomatoid transformation, similar to the characteristics of borderline PT. Transcriptomic and proteomic analyses demonstrated that epithelioid PTs are distinct from classical PTs in gene expression and protein abundance levels. Immunohistochemical analysis showed that among all differentially expressed proteins, epithelioid PT showed abnormal p16/retinoblastoma expression patterns, similar to those of malignant PT.
Epithelioid PT has unique morphological characteristics, biological behaviour and protein expression profile, which meets the diagnostic criteria of borderline PT and is prone to sarcomatoid transformation. It may be a special morphological subgroup of borderline PT and has partial characteristics of malignant PT, which should be taken seriously in pathological diagnosis and clinical management.
叶状肿瘤（PTs）是相对常见的纤维上皮性肿瘤，由上皮和间质成分组成。通常，PTs表现为具有成纤维细胞表型的梭形细胞形态，而一些肿瘤细胞表现出上皮样形态特征和肉瘤样转化。然而，这一形态学亚组的分子特征仍不清楚。本研究旨在总结7例具有上皮样特征的PT的临床病理、形态学和分子特征。
观察并检索形态学和临床病理特征。对7例上皮样PT进行免疫组织化学、免疫荧光和电子显微镜检查，以探索免疫表型和超微结构特征。进行转录组学和蛋白质组学分析，以比较上皮样PT和经典PT之间差异表达的基因和蛋白质。
上皮样PT患者表现出较高的复发率（42.8%）。形态学上，除了具有上皮样细胞学特征外，肿瘤间质细胞表现出中度至明显的异型性，且常表现出肉瘤样转化，类似于交界性PT的特征。转录组学和蛋白质组学分析表明，上皮样PT在基因表达和蛋白质丰度水平上与经典PT不同。免疫组织化学分析显示，在所有差异表达的蛋白质中，上皮样PT显示出异常的p16/视网膜母细胞瘤表达模式，类似于恶性PT。
上皮样PT具有独特的形态学特征、生物学行为和蛋白质表达谱，符合交界性PT的诊断标准，且易于肉瘤样转化。它可能是交界性PT的一个特殊形态学亚组，具有部分恶性PT的特征，在病理诊断和临床管理中应予以重视。
