Breast cancer screening is currently undergoing a major transformation. Long based on a conventional approach primarily guided by age and relying on mammography, it is gradually moving toward personalized screening, better adapted to the diversity of women’s profiles.

This paradigm shift is founded on a now widely shared observation: not all women have the same risk of breast cancer, the same breast characteristics, or the same follow-up needs. Breast density, personal or family history, age, hormonal context, and the repetition of examinations directly influence the performance of imaging modalities.

In this context, breast imaging goes beyond its historical role as a simple detection tool. It becomes a central component of risk stratification, at the heart of increasingly individualized medicine, in which the radiologist plays a key role.

Why Personalize Breast Cancer Screening?

Mammography remains the foundation of population-based screening and has demonstrated its effectiveness in reducing mortality. However, its performance is not uniform across all clinical situations. In certain patients, particularly those with dense breasts, its sensitivity can be significantly reduced, increasing the risk of undetected cancers.

Breast density now occupies a central place in screening considerations. It acts both as a masking factor for lesions and as an independent risk factor for breast cancer. Other determining parameters must also be considered, such as family history, personal history, and the age at which screening begins.

Personalizing screening therefore means adapting the imaging strategy — choice of modalities, frequency of examinations, and organization of the care pathway — in order to optimize detection while limiting false positives, overdiagnosis, and unnecessary radiation exposure.

The Pillars of Personalized Screening

Individualized screening relies on a reasoned multimodal approach, in which each technique provides specific and complementary information.

Mammography, increasingly combined with tomosynthesis, remains the entry point to screening. Tomosynthesis allows better visualization of breast structures by reducing tissue overlap, improving mass detection and decreasing unnecessary recalls. Despite these advances, limitations persist, particularly in patients with dense or extremely dense breasts.

Breast ultrasound plays an important complementary role. As a non-ionizing and widely available modality, it is particularly useful in young women and in those with high breast density. It can detect solid masses not visible on mammography and plays a key role in the targeted exploration of clinical or radiological abnormalities. However, its operator dependence and interobserver variability limit its use as a stand-alone screening tool.

Contrast-Enhanced Mammography (CEM) introduces a functional dimension by highlighting tumor enhancement, reflecting neoangiogenesis. It combines anatomical and vascular information, partially overcoming the limitations related to breast density. Quick to perform and relatively easy to integrate into a mammography workflow, CEM represents a relevant intermediate option, particularly when MRI is not accessible or is difficult to organize.

Finally, breast MRI stands out as the most effective modality in a personalized screening strategy. Independent of breast density, it combines detailed morphological analysis with advanced functional information, including dynamic contrast-enhanced and diffusion sequences. Its non-ionizing nature is a major advantage, especially in repeated follow-up strategies and in young patients.

Adapting the Strategy to the Patient’s Profile

The goal of personalized screening is not to multiply examinations, but to select the most appropriate combination for each patient. In women at low risk with non-dense breasts, mammography, with or without tomosynthesis, remains entirely appropriate. Conversely, in patients with dense or extremely dense breasts, complementary imaging becomes essential.

In this context, MRI has a clear role not only in patients at high genetic or familial risk, but also in those whose breast density compromises the effectiveness of standard examinations or who require iterative follow-up. CEM may be considered a functional alternative when MRI is not feasible, while ultrasound retains a targeted and pragmatic role.

Breast cancer screening is evolving toward a stratified, multimodal, and patient-centered approach. This evolution is based on a better understanding of risk factors, foremost among them breast density, and on a reasoned use of the different imaging modalities.

Rather than opposing techniques, personalized screening relies on their intelligent complementarity. This logic finds particularly concrete application in the management of extremely dense breasts, developed in the second article.