The two far ends of the age at the diagnosis of breast cancer are the age of younger than 35, and that of older than 70. Most probably, these two groups of patients differ in many ways. The aim of our present study was to underline the fact that age at the diagnosis of breast cancer is indeed a prognostic factor. Between October 1995 and March 2009, 80 old and 51 young breast cancer patients were treated at the Department of Diagnostic Radiology and Oncotherapy, Semmelweis University, Budapest. The prognostic and predictive factors of the tumors were analysed together with the disease-free and overall survival data. There were statistically significant differences between the two groups concerning the menstrual and reproductive factors, histological characteristics and immunophenotype of the tumors. Tumor size, nodal status and the Nottingham Prognostic Index did not show statistically significant differences. A trend to a shorter disease-free survival, higher rate of distant metastases and disease-specific death was seen in the group of young patients, but it was not significant. Overall survival was significantly shorter in the group of young patients. Therefore, we can state that young patients have a more aggressive disease and worse outcome. There is an increased importance of self examination in these groups, since both age groups are beyond the age limits of the screening population in Hungary. The media and primary school education as well should be involved in educating women concerning this aspect. The individual follow-up of young patients with positive family history should also be established.