18 October 2018
Breast cancer awareness month has had an explicit focus on prevention – that is, helping people to understand and reduce their risk of developing the disease. At PHG Foundation we have been examining how health systems can support populations and individuals to achieve this goal through developing disease prevention pathways based on a better understanding of risk and provision of the most effective preventative interventions, be it health promotion advice, screening or surgery. As scientific knowledge accrues and new technologies are developed, they are opening up options across preventive care. We have been examining what these possibilities are and how best to embed these within healthcare - including technologies relating to biomarkers, biosensors, apps and data analytics.
Evolving knowledge on breast cancer risk
As a leading cause of mortality worldwide, breast cancer is an important area for scientific research. Along with a focus on early detection and treatment an equally important area is trying to understand how we can help prevent the disease. Much of this revolves around a greater understanding of factors that lead to disease development and managing them appropriately to reduce risk. That lifestyle (e.g. diet, physical activity), life events (pregnancy, age of menarche) and genes influence our risk of developing breast cancer is well established. What is less clear is how these factors interact and act across a person’s life.
As science continues to delve deeper into this disease, a more refined understanding of breast cancer is beginning to emerge. The evolution of genomic technologies is honing our understanding of the genes associated with breast cancer and enabling the definition of molecular sub-types of disease. Studies are now beginning to examine breast cancers from the perspective of particular molecular sub-types. As science and technology progresses, in the future we may be able to better identify those individuals who are most likely to die from breast cancer. It is hoped this will allow health systems to better target preventative interventions and get the right advice or treatment to the right person at the right time. The likely near term and future changes to breast cancer prevention were discussed at our recent workshop.
Prevention from the individual, population and health system perspective
Moving from scientific insights to preventative interventions is not an easy task. It requires careful consideration about what the evidence base around this knowledge is, whom it is most likely to benefit and how to develop pathways to enable its use in an effective manner. This demands a careful balancing act, taking into consideration individual, populations and health system needs, benefits and harms.
From a population perspective, the general consensus is that for most people risk of developing the disease can be reduced by addressing their lifestyle. Therefore, governments and health systems need to consider how to create an environment that is conducive to a healthy lifestyle.
However, many different factors influence the development and progression of breast cancer and each of us will have a specific combination of these factors influencing our level of risk - from minimal to high. Personal decisions regarding preventative actions will require that individual women (and men) understand their own level of risk and the combination of factors specific to them. This may enable them to assess the benefits of addressing these factors – for example through behaviour change - given their individual circumstances. For health systems to support individuals in such decision making can be a challenge, given that lifestyle factors such as alcohol intake and weight are sensitive subjects for many individuals. Providing interventions aimed at these factors is also challenging given the many influences and motivators for change.
Helping those who are already on the disease trajectory while supporting people to maintain health and prevent illness will be an increasingly complex balancing act
The importance of considering evolving knowledge about breast cancer risk is highlighted by a flurry of new papers discussing a move away from a one-size fits all approach to breast cancer screening and prevention. Several clinical trials are looking at the inclusion of risk-assessment by combining lifestyle and genetic information and offering coaching as part of screening programmes. Currently, screening programmes select on the basis of age (i.e. above the age of 50) and do not actively offer preventative advice. It is hoped that a risk-adapted approach would allow women who participate in screening to better understand their risk factors and make informed decisions about subsequent interventions such as actions to lower their risk or participating in regular screening.
All this leads to a more complex prevention pathway requiring a greater diversity of players such as those able to communicate risk, radiographers and behaviour change experts, all addressing prevention of breast cancer. This may not be easy to deliver for health systems with limited resources and competing priorities. While prevention is a goal that many health systems aim for, it can be hard to deliver whilst dealing with acute problems. Helping those who are already on the disease trajectory while supporting people to maintain health and prevent illness will be an increasingly complex balancing act.