Spatial Distribution and Quantification of Mammographic Breast Density, and Its Correlation with BI-RADS Using an Image Segmentation Method.

Yi Goh,Zhen Lee,Christopher Lai

doi:10.3390/life11060516

Abstract

(1) Background: Mammographic breast density (MBD) and older age are classical breast cancer risk factors. Normally, MBDs are not evenly distributed in the breast, with different women having different spatial distribution and clustering patterns. The presence of MBDs makes tumors and other lesions challenging to be identified in mammograms. The objectives of this study were: (i) to quantify the amount of MBDs—in the whole (overall), different sub-regions, and different zones of the breast using an image segmentation method; (ii) to investigate the spatial distribution patterns of MBD in different sub-regions of the breast. (2) Methods: The image segmentation method was used to quantify the overall amount of MBDs in the whole breast (overall percentage density (PD)), in 48 sub-regions (regional PDs), and three different zones (zonal PDs) of the whole breast, and the results of the amount of MBDs in 48 sub-regional PDs were further analyzed to determine its spatial distribution pattern in the breast using Moran’s I values (spatial autocorrelation). (3) Results: The overall PD showed a negative correlation with age (p = 0.008); the younger women tended to have denser breasts (higher overall PD in breasts). We also found a higher proportion (p < 0.001) of positive autocorrelation pattern in the less dense breast group than in the denser breast group, suggesting that MBDs in the less dense breasts tend to be clustered together. Moreover, we also observed that MBDs in the mature women (<65 years old) tended to be clustered in the middle zone, while in older women (>64 years old) they tended to be clustered in both the posterior and middle zones. (4) Conclusions: There is an inverse relationship between the amount of MBD (overall PD in the breast) and age, and a different clustering pattern of MBDs between the older and mature women.

Highlights

According to the World Health Organization (WHO), female breast cancer has topped as the most diagnosed cancer worldwide [1,2]
When the whole population were further divided into Breast Imaging Reporting and Data System (BI-RADS) density groups for analysis, the mean age of 56.7 was statistically significantly (p < 0.001) younger in the denser breasts group when compared to the mean age of 61.8 in the less dense breasts group, (Table 1)
This study showed that mature women (64 years old); age was, a factor affecting the amount of Mammographic breast density (MBD), as evidenced by the mean age of 56.7 in the denser breasts and 61.8 for the less dense breasts groups

Summary

Introduction

According to the World Health Organization (WHO), female breast cancer has topped as the most diagnosed cancer worldwide [1,2]. Adipose tissues, which have a much lower X-ray attenuation coefficient than fibroglandular tissues, may be protective against breast carcinogenesis [5]. The X-ray attenuation coefficient of breast tumors is like that of fibroglandular tissue; breast tumors are shown as areas of radiodensity. High MBD was associated with a 1.8- to 6.0-fold increase in breast cancer risk [6,7,8,9]. Women of younger age have higher MBD than older women, breast cancer occurrence generally increases with age, with older women having the highest incidence rates of median diagnosis age at 62 and with the highest probability of being diagnosed with invasive breast cancer for women in their 70s [10]

Objectives

Methods

Results

Discussion

Conclusion