Objective: To investigate the clinicopathological characteristics of acidophil stem cell pituitary neuroendocrine tumors (PitNET)/adenoma. Methods: Five cases of acidophil stem cell PitNET/adenoma were diagnosed between May 2022 and July 2023 at the Second Hospital of Hebei Medical University, Shijiazhuang, China. The clinicopathological features of the tumor were analyzed by using histology, immunohistochemistry, and electron microscopy. The relevant literature was reviewed. Results: There were 1 male and 4 females, aged from 23 to 69 years. Patient 3 was 55 years old at the time of diagnosis and first surgery, and relapsed 5 years later. The patients' median age was 32 years. Patients 1 and 5 showed elevated blood prolactin, with various degrees of hormonal symptoms except Patient 3, who showed only tumor compression symptoms. Imaging studies showed that all cases involved the sellar floor. The tumors of Patients 1, 2 and 5 were closely related to the cavernous sinus segment of the internal carotid artery. The tumors exhibited a diffuse growth pattern with chromophobic to slightly acidophilic cytoplasm. A few of tumor cells showed chromophobic cytoplasm. The nucleoli were conspicuous. Intranuclear inclusion bodies and variably-sized clear vacuoles were observed occasionally. Under electron microscope, marked mitochondrial abnormalities were observed, including increased mitochondria number, expanded hypertrophy, and absence of mitochondrial ridge fracture. Some mitochondrial matrices were dense, while some were vacuolated. Conclusions: Acidophil stem cell PitNET/adenoma is a rare type of pituitary adenomas/PitNETs. It often has a more clinically aggressive manner with immature cells, diffuse expression of PIT1, prolactin, and varying degrees of growth hormone expression. Because of the obvious diversity of their clinical hormone status and hormone immune expression, the diagnosis of this type tumor is still a challenge.
目的： 探讨嗜酸性干细胞垂体腺瘤/神经内分泌肿瘤的临床病理学特点。 方法： 收集河北医科大学第二医院2022年5月至2023年7月病理数据库中诊断明确的5例嗜酸性干细胞垂体腺瘤/神经内分泌肿瘤，对其临床表现、影像学特征、病理学形态、免疫表型及电镜特点进行回顾性分析，并复习相关文献。 结果： （1）5例患者就诊年龄23~60岁，中位年龄32岁；例1为男性，例2~5均为女性；其中例3为复发病例，首次手术年龄55岁，5年后复发；（2）例1、例5出现血泌乳素升高，除例3外均有不同程度的激素症状，例3仅表现为肿瘤压迫症状；（3）影像学上均有鞍底下陷表现，例1、例2及例5肿瘤与颈内动脉海绵窦段关系密切；（4）病理组织学表现均呈现弥漫性生长方式，肿瘤细胞胞质大部分嗜酸性，少数细胞胞质呈嫌色表现，细胞核核仁明显，偶见核内包涵体；5例均可见散在分布的胞质空泡；（5）电镜观察到不同程度的线粒体数量增多，肥大扩张，线粒体嵴断裂消失，部分线粒体基质致密，部分空泡化。 结论： 嗜酸性干细胞垂体腺瘤/神经内分泌肿瘤是一种罕见的、生长迅速的侵袭性肿瘤，肿瘤细胞不成熟，弥漫性表达生长激素因子1，以泌乳素表达为主，不同程度的表达生长激素，因其临床表现不典型性及激素表达的复杂性，临床对此类型肿瘤诊断具挑战性。.