Zhang MingXun, Zhang AnLi, Li Yuan, Wang Wei, Wu HaiBo
Department of Pathology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230036, Anhui, China.
Intelligent Pathology Institute, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, Anhui, China.
Brain Tumor Pathol. 2025 Aug 27. doi: 10.1007/s10014-025-00513-3.
Primary papillary epithelial tumor of the sella (PPETS) is a rare sellar neoplasm characterized by distinctive papillary architecture and thyroid transcription factor 1 (TTF-1) expression. DNA methylation profiling suggests its classification within the posterior pituitary tumor category. Here, we report a case of PPETS in a 37 year-old female presenting with amenorrhea, featuring unique morphological and immunohistochemical characteristics. The tumor exhibited atypical reversed nuclear polarity and, notably, demonstrated positive expression of paired box 8 (PAX-8) and synaptophysin-findings not previously reported in PPETS. Following comprehensive evaluation, including DNA methylation analysis and exclusion of metastatic disease, the tumor was classified as a posterior pituitary tumor, confirming the diagnosis of PPETS. This case expands the known morphological and immunohistochemical spectrum of PPETS, highlighting the importance of careful differential diagnosis from pituitary adenomas and metastatic carcinomas. Further investigation is warranted to fully characterize the morphological variants and immunophenotypic diversity of this rare tumor type.
鞍区原发性乳头状上皮肿瘤（PPETS）是一种罕见的鞍区肿瘤，其特征为独特的乳头结构和甲状腺转录因子1（TTF-1）表达。DNA甲基化谱分析提示其可归类于垂体后叶肿瘤。在此，我们报告一例37岁出现闭经的女性PPETS病例，其具有独特的形态学和免疫组化特征。该肿瘤表现出非典型的核极性反转，并且值得注意的是，显示配对盒8（PAX-8）和突触素呈阳性表达——这些发现此前在PPETS中未见报道。经过包括DNA甲基化分析和排除转移性疾病在内的全面评估，该肿瘤被归类为垂体后叶肿瘤，从而确诊为PPETS。该病例扩展了已知的PPETS形态学和免疫组化谱，凸显了与垂体腺瘤和转移性癌进行仔细鉴别诊断的重要性。有必要进一步研究以全面描述这种罕见肿瘤类型的形态学变异和免疫表型多样性。
