Today the use of adjuvant treatment of breast cancer is unquestionable in the management of this disease. Both chemotherapy and hormonal therapy have proved to be beneficial, not only with respect to the reduction of the risk of recurrence, but also with respect to mortality. However, in elderly patients, this therapeutic approach is occasionally the subject of controversy, due to the undervaluing of the tumoral disease with respect to the multiple pathology frequently present in these patients. This study analyses a retrospective series of 100 patients more than 70 years old with breast cancer who underwent radical surgery between 1990 and 1998, with an extension study without evidence of metastasis and a minimum follow-up of 2 years. As occurs in the population of this age, in our series 77% of the patients presented with concomitant disease under medical treatment, and although the majority received adjuvant treatment with tamoxifen, the principal cause of death in this series was the breast cancer that had been diagnosed.