临床常见的乳腺非肿瘤病变有乳腺囊性增生病、导管扩张症（或浆细胞性乳腺炎）、积乳囊肿、脂肪坏死等。良性肿瘤中，以纤维腺瘤和导管内乳头状瘤多见。需与乳腺恶性肿瘤鉴别的常见病有：乳腺导管扩张症，脂肪坏死，硬化性腺病及巨纤维腺瘤。乳头状瘤病与乳头状瘤是两类性质截然不同的病变。病理组织学诊断为乳头状瘤病及非典型增生（主指Ⅱ～III级）的属癌前病变。目前尚无证据说明囊性增生病与乳腺癌的发生有关。

Main Points of diagnsis and differentiate diagnosis in benign diseases or lesions of the breast ZHANG Na, ZHANG Bin. Liaoning Province Tumor Hospital, Shenyang 110043, China Abstract Cystic hyperplasia, mammary duct ectasia （plasma cell mastitis）, milk cyst and fat necrosis were common benign non-neoplasm lesions of the breast. Among the benign neoplasms, adenofibroma （fibroadenoma） and intraductal papilloma were much more frequency. There are several benign breast diseases such as mammary duct ectasia, fat necrosis, sclerous adenosis and massive adenofibroma need differentiate from malignant lesions of the breast. Papillomatosis and atypical hyperplasia （grade 2 and 3）belong to premalignant lesions of the breast. Up to now, there are no evidence of the relationship between cystic hyperplasia of the breast and developing breast cancer.