Should the carbon footprint of imaging be considered to ensure an effective, sustainable supplementary breast screening strategy for women with dense breasts?

Breast density is an independent risk factor for breast cancer and reduces the sensitivity of mammography, increasing the chance of a missed breast cancer. Notifying women of their breast density aims to increase their awareness about their breast cancer risk and support discussions about supplemental screening (e.g. ultrasound or magnetic resonance imaging) with their healthcare providers. Although supplemental screening may improve cancer detection, it also brings challenges, including lack of international consensus on how best to manage screening in women with dense breasts. The implementation of breast density notification and supplemental screening will significantly impact global screening programs, and provides an opportunity to re-evaluate screening pathways, not only in terms of benefits and harms, but also environmental sustainability. In this perspective, we discuss the benefits and harms of supplemental screening for women with dense breasts, including the carbon footprint of screening, and considerations for clinicians, consumers and policymakers.