Objective: To study the clinicopathologic characteristics, immunophenotype, pathologic diagnosis and differential diagnosis of myxoid adrenocortical adenomas. Methods: The clinical data, histological features and immunohistochemical results of 4 cases of myxoid adrenocortical adenomas were analyzed, which were collected from January 2014 to December 2016 at Guangdong General Hospital, with review of literature. Results: Four cases of myxoid adrenocortical adenomas were presented. The patients ages ranged from 26 to 45 years (mean =35 years). Microscopically, it showed a typical morphology, characterized by small-sized tumor cell cords or pseudo-glands embedded in an abundant extracellular myxoid matrix. Immunohistochemical staining showed tumor cells were strongly positive for Melan A, vimentin and focally for α-inhibin, one case showed strong and diffuse positivity for CAM5.2, and two cases showed diffuse positivity for synaptophysin, while negative for CgA, S-100 protein, epithelial antigen, CK7, CK20 and CKpan. Conclusions: Myxoid adrenocortical adenomas are extremely rare, which may cause confusion with metastatic well-differentiated neuroendocrine tumours, sex cord-stromal tumoursor metanephric adenoma. Recognition of this entity would be beneficial for pathologists to avoid misdiagnosis, and unnecessary treatment.
目的： 探讨黏液样肾上腺皮质腺瘤的临床病理学特征、免疫表型、诊断及鉴别诊断。 方法： 回顾性分析广东省人民医院2014年1月至2016年12月收集的4例黏液样肾上腺皮质腺瘤的临床资料、病理形态学特征及免疫表型特点，并复习相关文献。 结果： 4例黏液样肾上腺皮质腺瘤患者26～45岁，其中女性1例，男性3例。肿瘤间质显著的黏液样变性，瘤细胞体积小，核圆形，胞质少－中等量，嗜酸性或透亮，呈条索状、腺管状或器官样排列；其中2例黏液区域占90%以上，1例占70%；而另一黏液区域为10%的病例，肿瘤形成广泛的腺管状结构。免疫组织化学显示4例波形蛋白与Melan A弥漫强阳性，局灶α－抑制素阳性；2例突触素阳性；1例CAM5.2阳性；4例嗜铬粒素A、S－100蛋白、上皮抗原、细胞角蛋白(CK)7、CK20及广谱细胞角蛋白均阴性。 结论： 黏液样肾上腺皮质腺瘤非常罕见，是一种良性肿瘤，应避免误诊为其他肾上腺原发或继发的恶性肿瘤，防止造成不适当的治疗。.
Keywords: Adrenal gland neoplasms; Diagnosis, differential; Immunohistochemistry.