A large-scale study mapping breast tissue from over 500 women has revealed how aging particularly menopause reshapes the tissue environment in ways that may increase cancer risk. Published in Nature Aging, the research shows that with age, breast cells decline in number and activity, structural components shift, and a tumor-supportive microenvironment can develop.

Researchers from the University of Cambridge and University of British Columbia used advanced imaging to analyze cellular, hormonal, and immune changes across ages 15 to 86. They found that milk-producing lobules shrink, ducts become more prominent, fat increases, and blood vessels decrease.

The immune landscape also changes significantly protective B and T cells decline, replaced by more inflammatory cell types, potentially reducing the body’s ability to eliminate abnormal cells. Additionally, reduced interaction between immune and epithelial cells may allow pre-cancerous cells to escape detection.

Overall, the findings provide new insight into why breast cancer risk rises with age and highlight menopause as a critical turning point in tissue and immune system remodeling.

Source: https://www.cam.ac.uk/research/news/most-detailed-map-to-date-of-breast-tissue-changes-reveals-role-of-menopause-in-cancer