DENSIDADE MAMOGRÁFICA EM MULHERES NA PÓS-MENOPAUSA USUÁRIAS DE TERAPIA HORMONAL DE BAIXA DOSE

Abstract

Objetives: To assess the effects between non-treatment (placebo group) and a low dosage estrogen-progestin regimen with norgestimate on changes in mammographic breast density (BD) in postmenopausal women after 12 months of hormone therapy. Methods: A prospective study was performed with 40 postmenopausal patients from Materno-Infantil University Hospital (São Luís, Maranhão), divided into two groups: treated ( n=20) using 1 mg of beta-estradiol (E2) and 1mg of E2 + 90mcg norgestimate (NMG); and control (placebo). One-hundred sixty mammograms were done before and after a 12-month period of hormone therapy and BD between the two exams in each group was compared. BD was measured by two qualitative methods (Wolfe and Breast Image Reporting and Data System BI-RADS classification) by two different observers. Data were analysed using Epi- Info program, with statistical significance of 5%. Interobserver variability from mammograms was considered low in both classifications, as well as there were a high percentage of agreement between the two methods. T-student test was used for means and Fisher test for binomial variables. Results: Both groups were considered homogeneous. Body mass index (BMI) did not change during the study period in both groups. Mammographic breast density s classification according to Wolfe was respectively in treated and placebo groups, N1=12, P1=5, P2=3, DY=0; and N1=11, P1=6, P2=3, DY=0, before and after low dose hormone therapy, with no significant differences. A similar pattern was observed at placebo group using Wolfe classification. There were no significant changes in BD according to BI-RADS category in both groups. Conclusion: Low dosage hormone therapy with norgestimate was not associated with increased BD after 12 months of treatment, supporting current literature. Further studies using devices with better technology in analyzing BD are needed to confirm a stability of breast epithelium with different types of low dosage hormone therapy.