Aim of the study is to evaluate the biology, the clinical evolution and the prognosis of lobular carcinoma of the breast. We retrospectively evaluated the patients treated in our institution during the last 13 years. 117 patients with lobular carcinoma of the breast and 117 patients, randomized out of 397 patients with 'classical' pattern of ductal carcinoma were compared. Age distribution, type of surgery, tumor size, TNM stage, axillary lymph node involvement, multifocality, multiple breast cancers, local and distant recurrences, overall survival and disease-free survival have been evaluated. There was not a significant difference in tumor size, lymph node involvement, stage distribution, estrogens and progesterone receptors status, local and distant recurrences. The only significant differences were found in multifocality and multiple breast cancers. The said difference does not seem to modify the overall survival and the disease-free survival that are the same in the two groups. Our research shows that tumor size and axillary lymph node status are the only elements that have to be considered in the choice of the surgical treatment and prognosis. It seems that the difference in distant metastatic pattern between lobular and ductal carcinoma is the distinctive feature in the follow-up of these patients.