在过去的五十年里，乳房密度被认为与患乳腺癌的风险增加有关。根据美国放射学院乳腺成像报告和数据系统（BI-RADS）的定义，乳腺组织密度分为异质性密度和极度密度两个子组。增加的乳腺X线摄影密度与腺体组织丰富程度之间存在统计学上显著的相关性，然而这种相关性的强度较弱。尽管目前尚不清楚乳房密度相关肿瘤起始和进展的机制，但有证据表明，参与上皮与间质相互作用的某些分子途径可能在纤维蛋白原胶原沉积、基质硬度增加和细胞迁移方面发挥关键作用，从而促进乳房密度和癌变。本文将这些分子机制描述为乳房密度相关癌症的潜在"造园师"。我们还介绍了"乳房致密度"一词，用以反映胸部CT扫描中乳房组织的胶原密度，以及使用乳房硬度测量作为乳腺癌筛查和风险分层的成像生物标志物。©2023 BioMed Central Ltd.，Springer Nature的一部分。

Over the last five decades, breast density has been associated with increased risk of developing breast cancer. Mammographically dense breasts are considered those belonging to the heterogeneously dense breasts, and extremely dense breasts subgroups according to the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). There is a statistically significant correlation between the increased mammographic density and the presence of more glandular tissue alone. However, the strength of this correlation is weak. Although the mechanisms driving breast density-related tumor initiation and progression are still unknown, there is evidence suggesting that certain molecular pathways participating in epithelial-stromal interactions may play a pivotal role in the deposition of fibrillar collagen, increased matrix stiffness, and cell migration that favor breast density and carcinogenesis. This article describes these molecular mechanisms as potential "landscapers" for breast density-related cancer. We also introduce the term "Breast Compactness" to reflect collagen density of breast tissue on chest CT scan and the use of breast stiffness measurements as imaging biomarkers for breast cancer screening and risk stratification.© 2023. BioMed Central Ltd., part of Springer Nature.