近二十多年来,透射电镜的应用已证实多形性腺瘤中的细胞巢和导管样结构由上皮组成。而对该肿瘤中的粘液样、软骨样组织的起源一直有争议,welsh 等人认为是间质起源,坚持该肿瘤是中、外胚层共同起源的混合瘤,Hübner,Batsakis等则认为是上皮形成,该肿瘤是单纯上皮起源。目前,肌上皮 For more than two decades, the use of transmission electron microscopy has confirmed that the nests and duct-like structures in pleomorphic adenomas are composed of epithelium. The origin of mucin-like and cartilage-like tissue in this tumor has been controversial. Weshsh et al. believe that it is the origin of mesenchyme and insists that the tumor is a mixed tumor of the common origin of mesoderm and ectoderm. Hübner and Batsakis et al. believe that it is epithelial. The tumor is of simple epithelial origin. Currently, myoepithelial