Ahead of her lecture at the GOLD Lactation Online Conference in 2021, Wendy spoke to Fiona Lang-Sharpe about what inspires her in her work, and why breast research is so important.

Improving breast health throughout the life course

The breast is a unique organ, because it goes through most of its development a long time after birth. For example, puberty is a really important phase in breast development, as is pregnancy. This development is key in enabling the breast to perform its critical function in producing milk to nurture a new baby, but it also affects the risk of breast cancer for a woman's entire life. We know that the breast is the most susceptible tissue in a woman's body for developing cancer, so it's very important to understand how it grows and functions. Our research focus is on studying how the breast functions and how disease states can develop in the breast, such as breast cancer and lactation mastitis, and how this information can be used to improve women's breast health for the life course.

Breast Biology & Cancer Unit - 'prevention for the future'

Wendy leads the Breast Biology & Cancer Unit, based at The Queen Elizabeth Hospital. The research focus is on understanding the underlying biology of breast function and risk of disease. The Unit works closely with a broad range of clinicians, communication experts and community groups so that new discoveries will translate into improved prevention, detection and treatment decision-making, with the ultimate goal to improve breast health outcomes. Research projects are available for Honours, Masters and PhD students.

Breast cancer prevention research

Breast cancer places an incredible burden on Australian women. Every year, around 20,000 Australian women are diagnosed with breast cancer alone - a disease that devastates people's lives and is often fatal. If we are to prevent breast cancer, we must better understand how the disease develops. This research studies the biological mechanisms of two different risk factors - breast density and menstrual cycling.

Why breast density matters in prevention and detection of breast cancer

Breast density (also known as mammographic density) is the percentage of white and bright regions on a mammogram. Breast density is not related to how breasts look or feel and can only be assessed by mammogram. High breast density is both an independent risk factor for breast cancer and masks cancers on a mammogram. Combined, these two distinct phenomena lead to increased incidence, delayed diagnosis, more aggressive tumours, and a 90% increased risk of breast cancer-associated death in women with high breast density. Learn more about breast density here.

Despite the difficulties breast density cause in the detection of breast cancer, there is exciting potential for breast density to become a widespread health assessment tool, used to identify the women most at risk of breast cancer in order to intervene early and reduce that risk. Our research is the first to demonstrate a causal role for immune system signalling in breast density and the associated cancer risk, opening the door for new approaches to reduce breast cancer risk through use of anti-inflammatory drugs in women with dense breasts. Find out more about this discovery in Wendy's ABC Health Report podcast with Dr Norman Swan.

Immune cells open a window of breast cancer risk each menstrual cycle

Menstrual cycling increases a woman's risk of breast cancer. For each year younger a girl starts menstruating (i.e. having a period each month), there is a 5% increased risk of breast cancer over her lifetime. Our research has focused on immune cells known as macrophages in the breast, and how the role of these cells changes because of fluctuations in hormones during different times of the month. We have discovered that while the immune cells have a role to play in the normal function of the breast, at certain stages in the menstrual cycle they may help to make the breast more susceptible to cancer. Learn more about this discovery here.

Improving breast cancer treatment decision-making

Gene expression profiling of breast cancer is a technology increasingly being adopted in the clinic as a precision medicine approach to tailor treatment to individual patients. However, an underappreciated factor in breast cancer diagnosis in young women is that oestrogen and progesterone fluctuate dramatically during the menstrual cycle, and these hormones are likely to affect gene expression. We have shown that the menstrual cycle can affect precision medicine which could in turn affect treatment decision-making. This research has led to the TRIAGE project (Treatment Response Independent of AGE); a collaboration with industry partners including SA Pathology that aims to ensure patients of all ages can access the best advice about how to treat their individual breast cancer.

Lactation mastitis and breastfeeding research

Lactation mastitis is an inflammatory breast disease affecting 1 of 5 Australian breastfeeding women. It causes pain, fever and low milk supply. The challenges posed by this disease lead many women to use supplementary formula, or cease breastfeeding altogether leaving their infants at increased risk of respiratory and gastrointestinal diseases as babies, and non-communicable diseases including heart disease, obesity, diabetes, cancer, allergies, asthma, mental illness and chronic lung, liver and renal diseases as both children and adults. Our research has suggested that macrophages play a role in development of this disease. The ROBIN study (Risk Of Breast INflammation) is now exploring revolutionary new concepts of how immune cells function in the breast, and how these cells affect breast disease development. Learn more about lactation mastitis in Wendy's podcast for the Australian Breastfeeding Association.