乳腺导管内增生性病变是一组形态学结构复杂多样、与乳腺癌关系十分密切的病变。WHO(2003)乳腺肿瘤组织学分类重新诠释了它的概念,将其命名为导管上皮内肿瘤并在后面附上数字以表明增生或不典型增生的程度。本文着重介绍各类导管内增生性病变的组织病理学特点、遗传学改变及其与浸润性癌的关系。 Mammary duct hyperplasia lesions is a group of complex and diverse morphological structure, and breast cancer are closely related to the disease. WHO (2003) Histological classification of breast tumors reinterpreted its concept as a ductal intraepithelial neoplasia with a number appended to indicate the extent of hyperplasia or dysplasia. This article focuses on the various histopathological features of proliferative lesions in the catheter, genetic changes and its relationship with invasive cancer.