For thousands of children and young adults in British Columbia who have survived cancer, growing up can be an ongoing battle with long-term effects from life-saving treatments. Milestones that their peers take for granted—graduation, first job, marriage, and children—may seem unattainable.
Help may be coming for survivors of childhood cancer from an unlikely source—numbers, lots of them. A wealth of patient and population health data in British Columbia is revealing important clues that will help support survivors in their ongoing journey towards adulthood.
“Thanks to tremendous advances in treatment options, more than 80 per cent of children diagnosed with cancer would be expected to survive at least five years,” says Mary McBride, Distinguished Scientist at the BC Cancer Agency (BCCA) and a clinical associate professor at UBC’s School of Population and Public Health. “But these life-saving treatments often have challenging consequences.”
McBride says the majority of cancers that affect children—such as leukemia and lymphoma—are inoperable since they affect whole body systems. Others, such as brain tumors, are extremely difficult to operate on. Chemotherapy and radiation therapy for these cancers, while effective, can damage healthy cells and organ systems. Bone cancer, such as the type suffered by Terry Fox, may be treated by surgery, but often requires amputation and can lead to negative physical and psychological effects.
“These after-effects started to become evident in the mid-1990s as the cohort of childhood cancer survivors grew,” says McBride. “Today, 70 per cent of childhood cancer survivors in B.C. are over the age of 20, and at least one-third of them may have chronic health conditions that require long term treatment.”
In addition to reoccurrence of their first cancer, childhood cancer survivors are at risk of developing second cancers, heart disease and endocrinological and neuropsychological abnormalities. They are also more likely to suffer from infertility and low marriage rates and experience discrimination in the workplace and the education system.
The Childhood, Adolescent and Young Adult Cancer Survivor (CAYACS) research program was designed specifically to address this growing need for long-term care. Unique in the world, the program involves researchers from UBC, BCCA, BC Children’s Hospital and Simon Fraser University and utilizes multiple provincial government datasets held at UBC (PopDataBC and EduData Canada, for example), and BCCA’s extensive cancer data holdings to identify risk patterns—and how the healthcare system can most effectively and efficiently support cancer survivors.
The CAYACS Program, with detailed, anonymized information on more than 3,800 childhood cancer patients who have survived five years or more, is one of the most comprehensive such datasets in the world. The research team at UBC, with expertise ranging from population health to statistics, counseling psychology and special education, helps interpret the data with the aim of ultimately developing protocols and guidelines in collaboration with family physicians and oncologists.
“Due to treatment being given during active periods of physical and cognitive development, at least two thirds of this cohort of survivors will suffer long-term after-effects; and one third will experience a significant disability from long-term side effects,” says Dr. Paul Rogers, a pediatric oncologist at BC Children’s Hospital, clinical investigator at the Child & Family Research Institute and a clinical professor at UBC. “CAYACS has documented this cohort’s increased utilization of the healthcare system in B.C., which could inform policymakers of the need for coordinated, long-term surveillance in order to facilitate early detection of emerging health concerns.”
“This research is both pioneering and eagerly anticipated by family physicians,” says Dr. Jim Thorsteinson, executive director of the BC College of Family Physicians. “Knowing that past history of childhood cancer has significant implications for the patient’s current and future health and what types of problems are most of concern will allow us to work more closely with individuals to guide them in healthy choices and to monitor their specific risks.”
“In B.C. we have a unique alignment of research, clinical care and government support that allows us to take a comprehensive look at how factors such as age of diagnosis, socio-economic status and treatment type impact long-term prognosis,” McBride adds. “The constellation of strengths, coupled with the wealth of data, puts us in an excellent position to make a tangible difference in these people’s lives.”
The Childhood, Adolescent and Young Adult Cancer Survivor (CAYACS) research program is funded by the Canadian Cancer Society (CCS) Research Institute and the CCS BC and Yukon Division.