正确诊断原发性肺癌的组织学类型,对临床上决定手术适应症,选择治疗方案,判断预后均甚重要。然而,肺癌组织结构复杂,分类繁乱,未分化型癌尤难准确归类。本文对光镜确诊的12例未分化型肺癌作了电镜观察,试图从超微结构水平上探索它的组织来源、形态特征以及与其他型肺癌之间的关系,并在此基础上讨论未分化型肺癌是否是 Correctly diagnosing the histological type of primary lung cancer is important for clinically determining the surgical indications, selecting the treatment plan, and determining the prognosis. However, the structure of lung cancer is complicated and classified, and undifferentiated cancer is difficult to accurately classify. In this paper, 12 cases of undifferentiated lung cancer diagnosed by light microscopy were observed by electron microscopy, attempting to explore its source of tissue, morphological characteristics, and the relationship with other types of lung cancer from the ultrastructural level, and on this basis to discuss the undifferentiated Is lung cancer