Fibrocystic mastopathy (FM), a benign lesion, is considered by many author like a premalignant lesion. Breast carcinoma (CA) represents the most frequent female tumor and the second mortality cause through cancer, after the bronchopulmonary cancer. At the Department of Pathology from Tg. Mureş, we selected 190 cases, for 10 month: 102 presented FM, 41 CA and 47 CA + FM. In every case, we have examined 2 slides stained with HE. In difficult cases, we performed special stains (van Gieson, H-PAS, Alcian). We studied the pulmonary tumor, adjacent mammary tissue and axillary lymph nodes. The present data of literature and the experience of the Department of Pathology from Tg. Mureş showed a strong relationship between the presence of FM and the appearance of CA: both lesions have a common field of hormonal disfunction and intraductal and intralobular hyperplasia (an microscopic feature of mastopathy) increase the risk of CA.