Analysis of Breast Parenchymal Density on Mammograms in relation to Age and Parity among northeastern Nigerian women

Abstract

AIMS: To Correlate Breast Parenchymal Densities among Northern Women who attended Clinic Screening in relation to age and Parity. Study design: Retrospective study. Place and Duration of Study: Department of Human Anatomy College of Medical Sciences University of Maiduguri and Department of Radiology, University of Maiduguri Teaching Hospital (UMTH), between July 2010 and March 2011. Methodology: Parenchymal densities of Screened mammograms were assessed visually on both cranio-caudal and medio-lateral oblique views. The documented parenchymal densities were categorised using BIRADS categorization based on the ‘BR’ technique used in Department of Radiology, University of Maiduguri Teaching Hospital (UMTH). The ‘BIRADS’ technique involves four values given to a mammogram depending on its density. BR1 – Predominantly Fatty; BR2 – Scattered Fibro glandular Densities BR3 – Heterogenously Dense; BR4 – Very Dense Breast Tissue The subcutaneous and retromammary fat regions in each breast were excluded during the determination of dense tissue. In patients with asymmetric tissue, breast with greater density was categorized. For each patient, benign or probably benign calcifications were not recorded. Results: Parenchymal density on mammograms decreased progressively from the age cohort of 25-29 years old in which 38% had predominantly fatty breasts through the cohort of 75-79 years old, in which 100% had predominantly fatty breasts. In cohort of 40-44 years, 32% had scattered fibro glandular densities. In cohort of 45-49 years, 31% of patient had scattered parenchymal densities. Five or more pregnancies were associated with predominantly fatty breasts in 34 women compared with null parity or one pregnancy. Conclusion: Younger age and fewer than two pregnancies are significantly associated with, but not highly predictive of increased parenchymal density on mammograms. Significant percentages (38%) of women 25-29 years old have predominantly fatty breast tissue on mammograms that should not impede selective mammographic screening or diagnostic effort in this age group. Further investigations could be carried out with other parameters such as benign or malignant calcifications seen on mammographs so as to predict and prevent breast cancer at early stage.