[Correlation between breast density and age, breast cancer molecular subtype]

Area of Science:

• Oncology
• Radiology
• Pathology

Background:

• Breast density is a known risk factor for breast cancer.
• Breast cancer is a heterogeneous disease with distinct molecular subtypes.
• Understanding the relationship between imaging findings and molecular characteristics is crucial for personalized medicine.

Purpose of the Study:

• To investigate the association between mammographically determined breast density and the molecular subtypes of breast cancer.
• To analyze this correlation across different age groups.

Main Methods:

• Retrospective analysis of 1,407 breast cancer cases with immunohistochemistry and mammography data.
• Correlation analysis between breast density and age using Pearson correlation test.
• Comparison of breast density across molecular subtypes (Luminal A, Luminal B, HER2-enriched, triple-negative) using Kruskal-Wallis test, stratified by age groups.

Main Results:

• A significant negative correlation was observed between breast density and age (r=-0.55, P<0.01).
• Mean breast density decreased with increasing age across all groups.
• Significant differences in breast density among molecular subtypes were found only in women younger than 45 years (P<0.05).
• No significant differences in breast density among molecular subtypes were observed in older age groups (P>0.05).

Conclusions:

• Breast density is correlated with breast cancer molecular subtypes in younger patients.
• The potential of breast density as an indicator for breast cancer molecular subtypes requires further investigation, particularly in younger populations.