What compels a twelve year old to commit to a five-year research study? It’s a mixture of cool and curiosity. Just ask Mackenzie Perry, who volunteered to participate in the largest breast cancer study of its kind in Canada. Led by Mount Sinai scientists the goal of the study is to understand the influence of behaviour, environment and diet on pubertal growth in girls aged six to 13 and how these factors might impact their risk of breast cancer later in life.
“My mom told me about this project when she was diagnosed with breast cancer,” said Mackenzie. “I just wondered…if your parent wasn’t diagnosed with cancer, whether you still had a good chance of getting it. And because my mom did have it, what that meant for me. I thought the study was kind of cool.”
Mackenzie was just shy of her 13th birthday when she signed up. Now every six months, she and her mother travel from Stoney Creek, Ontario to downtown Toronto – an almost two-hour bus ride — to fill out questionnaires and give blood, urine and saliva samples.
The research study, named the LEGACY Girls Study, looks at whether the habits and development of young girls are related to breast health in older women. The unique initiative will enrol an estimated 180 girls in Ontario as well as their parent or guardian, and contact them every six months for follow up. Like Mackenzie, half of the girls in the study will come from families with a history of breast cancer, while the other half will come from families with no history of the disease.
Drs. Irene Andrulis and Julia Knight, Senior Investigators at Mount Sinai’s Samuel Lunenfeld Research Institute will have finished recruiting all of the girls in the Canadian arm of the study in the first half of 2013. They are working closely with their American colleagues in San Francisco’s Bay Area, New York, Philadelphia and Utah, which are also all sites of the Breast Cancer Family Registry.
As a molecular geneticist and also the principal investigator of the LEGACY study, Dr. Andrulis explores the clinical importance of genetic alterations to identify risk factors and lifestyle modifications
early enough to prevent or diminish the effects of cancer. The ultimate goal is to identify measures that could be taken to prevent breast cancer and to identify novel targets for new cancer therapeutics.
“In a previous study, we identified families with alterations in genes that increase the risk of breast cancer. The women in that study asked us how our efforts would help their daughters…and so that’s partly how the LEGACY study came about,” said Dr. Andrulis. “We designed the LEGACY study to find out what other factors are involved in breast health in addition to the genes we know about – factors such as diet, lifestyle, physical activity, even levels of Vitamin D.”
In addition to collecting questionnaires and biospecimens, the LEGACY study staff are also studying the breast tissue composition of these young girls when they are assessed for body measurements during each visit, using a technique called optical spectroscopy. The technique – developed by Dr. Lothar Lilge, Senior Scientist at the Ontario Cancer Institute and also one of the study’s investigators – involves holding a light probe over parts of the breast for about 30 seconds. From this, different wavelengths of light can provide information about the breast’s water and fat composition.
Dr. Julia Knight, an epidemiologist and co-principal investigator of the LEGACY study, will analyze the study’s results when enough baseline data has been gathered this year. She is working to bring the optical spectroscopy tool to Mount Sinai’s Prosserman Centre for Health Research.
“Optical spectroscopy is actually one of the few tools we have to gather data on changes in breast health as these girls mature into young women. With this new tool, we will be able to quantify how much variation there is in fat, water, and collagen in breast tissue over time and we hope that this will tell us about breast cancer risk at an early stage,” said Dr. Knight. “Compared to mammography, which carries significant radiation exposure for a young woman, optical spectroscopy is harmless and gives us a way to see what’s changing in the breast tissue very early on.”
Danielle Hanna, a certified genetic counsellor at the Ontario Familial Breast Cancer Registry and co-ordinator of the LEGACY Girls Study, commented that so far since the study began, not a single mother/daughter pair has dropped out. Although the two-hour assessment is typically long for a study visit, interactive aspects of the visit keep the young girls engaged.
“The girls participate in what we call our Junior Scientist Program, which takes place after the assessments and questionnaires wrap up. It’s a big draw for the girls because they’re taken into a real lab here at Mount Sinai and actually get to see how their samples are processed for the study. They also get to participate in hands-on activities using actual lab equipment. In a way, we’re mentoring future scientists,” said Danielle.
Funded by the U.S. National Institutes of Health (NIH), the LEGACY Girls Study will potentially create a recipe for a number of preventive measures that girls can follow as early as age six, in order to reduce their risk for breast cancer in the future.
Mackenzie admits that her habits are already changing just from filling out the study questionnaires. “There are questions that ask about how much exercise you do in a week, and it makes me wonder if I am doing enough,” she said. Referring to her friends who she also told about the study, and even helped recruit to the control group, Mackenzie added thoughtfully, “I think we’re all changing.”