INTRODUCTION: in the past decades, significant changes have occurred in diagnostic and therapeutic modalities of breast diseases. The “Hospital das Clinicas” of the Federal University of Minas Gerais (HC-UFMG) is a public reference service for patients with benign and malignant breast diseases. In 1989, the Laboratory of Breast Pathology (LBP) of the School of Medicine was inaugurated. Also, a protocol was created specifically for the examination of breast specimens, and has been used ever since. These protocols are important because they provide essential information for the clinical and surgical management of patients and, in breast cancer, they also include prognostic information. The aim of this study is to evaluate how the diagnosis and epidemiology of breast diseases have changed from 1989 to 2008 in the HC-UFMG, using information provided by this specific breast pathology protocol. METHODS: All breast pathology reports available from the study period were reviewed. Time was divided in four periods of five years (1989-1993, 1994-1998, 1999-2003 and 2004-2008). Frequencies of type of material received over the years and diagnoses were compared using the chi- square test, and patient’s ages with the Kruskal-Wallis test. RESULTS: During the study period, 12, 662 breast specimens from 7, 885 patients were received in the LBP. Comparing the period from 1989 to 1993 and from 2004 to 2008, the proportion of mammoplasties and excisional biopsies have decreased; the first, from 35, 8% (716 specimens) to 20, 7% (852 specimens), and the second from 31. 1% (622 specimens) to 18. 2% (750 specimens, p<0. 001). Second opinion exams have increased from 1. 6% (32 cases) to 11. 7% (481 cases). As for histology, there has been a decrease in the proportion of normal breasts (698 cases, 34. 9%, to 537 cases, 13.5%) and an increase in the proportion of breast carcinomas (469 cases, 23.5%, to 1694 cases, 42.5%, p<0. 001). Patient’s ages have changed from a mean of 39. 0 years (± 16. 0) in the period from 1989 to 1993 to 48. 3 years (± 15. 7) in the period from 2004 to 2008. DISCUSSION: There were changes in the proportion of types of breast specimens received over time, as well as in characteristics of patients submitted to exam or treatment in the HC-UFMG. For instance, core biopsy has been used since 1995, in many cases replacing excisional biopsies. The LBP also became reference in the evaluation of breast specimens as a breast consultation service. CONCLUSIONS: The changes in specimens received over time as well as their characteristics reflect changes in the management of breast diseases over time. FINANCIAL SUPPORT: CNPq, FAPEMIG, CAPES