The World Health Organization (WHO) classifications of tumors offer invaluable support in the diagnosis of tumors, with every new edition including novel information and diagnostic updates. The new 2017 WHO Classification of Tumors of Endocrine Organs, 4th edition, includes innovations in both terminology and diagnostic guidelines for pituitary adenomas, along with new entities, molecular information, and novel treatment modalities. The recommended reporting system of pituitary adenomas is based on morphology and assessment of the hormonal content by immunohistochemistry. Electron microscopy and immunohistochemistry for Ki-67 and p53 and transcription factors, while presenting additional information, are not recommended for routine diagnosis. Other markers may also yield information of prognostic and predictive significance. In sum, the 2017 WHO classification provides pathologists and clinicians with new and comprehensive information of great use for the diagnosis and treatment of pituitary tumors.

世界卫生组织 (WHO) 的肿瘤分类为肿瘤诊断提供了宝贵的支持，每一个新版本都包含新信息和诊断更新。新的 2017 年世界卫生组织内分泌器官肿瘤分类第 4 版包括垂体腺瘤的术语和诊断指南方面的创新，以及新实体、分子信息和新的治疗方式。推荐的垂体腺瘤报告系统基于形态学和免疫组织化学对激素含量的评估。Ki-67 和 p53 以及转录因子的电子显微镜和免疫组织化学虽然提供了额外的信息，但不推荐用于常规诊断。其他标志物也可能产生具有预后和预测意义的信息。总共，