RESUMO
BACKGROUND: This prospective study compares the characteristics of cystic disease of the breast (CDB) of patients who developed breast cancer (BCa) during the follow-up (1.25-4 years) period with those who did not. MATERIALS AND METHODS: K+, Na+, albumin, dehydroepiandrosterone (DHA), DHA-sulphate, oestrone, oestradiol, testosterone and progesterone levels were determined in breast cyst fluid (BCF). Patients presented data about their menstrual status, reproductive history, lactation period, date of first and the number of BCF aspirations, gynaecological interventions, use of oral contraceptives, family history of cancer, smoking habits and coffee consumption. The BCa incidence of patients was compared with the expected number of BCas in an age-matched group of 5143 women. RESULTS: Out of 147 patients 6 developed BCa. The standardized incidence rate was 6.29. There were significant differences in testosterone, oestrone and progesterone levels and also reproductive history of patients who developed BCa compared with patients without BCa. CONCLUSION: The above markers outline a subgroup of patients with the highest BCa risk.