Many people wonder why we don’t have a cure for cancer yet. While we have made a lot of progress in research, curing cancer isn’t easy. Why? Cancer isn’t just one disease. It is more than 100 diseases, and each of these 100 types is divided into several sub-types. So we are looking for many cures for many types of cancer. Cancer research is also a slow, step-by-step process. It involves collecting and analyzing information from lab research and studying people with cancer. What looks very promising in the lab doesn’t always work with people. It can often take many years before a new test or treatment is available outside of a clinical trial.
Even so, it’s an exciting time. Cancer research in Canada and around the world continues to move us closer to the day when many cancers will be curable and others will be managed as chronic diseases like diabetes and asthma. Advances in technology have helped us understand more about what causes cancer, how it develops, how to prevent it, how best to treat it and how to improve the quality of life of people living with cancer.
Cancer research has led to people with cancer surviving longer. Today, more than 60% of Canadians diagnosed with cancer will survive at least 5 years after their diagnosis. This is a big improvement over the 1940s when the 5-year survival was about 25%. As our knowledge grows, we will make even greater progress against cancer.
Cancer research covers a wide range of activities and aspects of scientific study. These types of cancer research are improving our understanding of the disease.
Basic cancer research
Basic cancer research helps us understand how cancer starts, grows and spreads (metastasizes). It’s all about cells and it takes place in the lab, where researchers focus on understanding the differences between normal, healthy cells and cancer cells.
The cells that are studied can be taken from tumours in people. Cancer cells can be grown in test tubes or other lab equipment, or even in animals, like mice, to see if they develop cancer. When animals are used to study cancer, researchers can also test new possible treatments and begin to understand the side effects related to a new treatment.
The more we learn about cancer cells, the more we can understand why some treatments work and other treatments don’t. Researchers doing basic cancer research look at the unique features of cancer cells, such as the genes that are turned on or off or certain substances found on cancer cells (called tumour markers). Understanding more about these features can help doctors make a diagnosis, predict a prognosis and plan treatment for people with cancer.
Researchers are also trying to learn more about the tumour microenvironment. This is the area that surrounds cancer cells inside a tumour. The way cancer cells interact with the tumour microenvironment will help us to learn more about how cancer develops, grows and spreads, as well as why some tumours are sensitive to some treatments but resistant to others.
Translational research tests what we’ve learned in the lab and takes it to the bedside of patients – and then goes back to the lab to find out more. Theories that are generated from experiments using cancer cells or animal models need to be validated in real human cancers using patient data or tumour samples. Researchers take what is learned using basic research about how cancer starts, grows and spreads and see if this knowledge matches what is seen in people with cancer. The results gained at the “bedside” of people with cancer are used to revise the theories which are then taken back to the lab to see if the information can be used to discover better treatments for patients.
Getting what we’ve learned in the lab used in the real world of cancer patients often takes a very long time. It takes many lab experiments and tests in humans (called clinical trials) to prove that a certain test or treatment will give more benefit than harm in people with cancer.
Once researchers find a promising idea to test based on results of translational research, they can start testing their ideas in larger groups of people. Clinical research is one of the most important ways we can improve how we treat and manage cancer as well as understand what raises or lowers a person’s risk of developing cancer.
Clinical trials are research studies that test new ways to prevent, find, predict prognosis of or treat cancer. Clinical trials also look at ways to make life better for people with cancer. Canada is an international leader in conducting clinical trials.
Clinical trials allow us to carefully study a promising treatment or a suspected link between cancer and a substance or behaviour. Cancer treatments often seem to work well in lab tests or in small groups of people. But researchers have to show that these treatments are safe and work well in a large group of people before Health Canada will approve them to be given by doctors to people with cancer.
Database and chart review studies
Database and chart review studies look at information from people with cancer in hospital records or a database of information like a cancer registry. Cancer databases store information about particular groups of people with cancer, such as those with a certain type of cancer, so that research can be done in the future. These studies help find out which people in a particular group are most or least likely to benefit from an available test or treatment and also help researchers understand if treatments are cost-effective.
During many types of research studies, a lot of data is collected to answer one question in a study. But researchers often gather extra information that could help answer many other questions that aren’t part of that study. Researchers are trying to figure out the best ways to store, share and study this extra data, which is sometimes called big data, to help answer research questions in the future.
Respecting patients’ privacy is very important when conducting research using data collected from patients. Database managers make sure that researchers do not have personal identifying information about patients, only the biological information about their cancer and the other information gathered for the study.
Population-based research uses databases that keep track of information about a large group of people (such as all people in a province who develop cancer over a certain period of time) to try to find the causes of cancer. Researchers compare risks of specific cancers in different populations of people with cancer according to factors such as age, sex, race or ethnicity, family history of cancer, your place of birth and where you work. We also know that some people have a higher risk of cancer based on their socioeconomic status – that is a person’s economic and social position based on their income, education and job. Looking at certain populations helps researchers get clues about the important causes of a particular type of cancer.
Population-based research also looks at the quality of cancer care and access to cancer care in different communities across the country. This can show us where cancer care needs to be improved the most.
Research looking at the differences in cancer incidence, death due to cancer (called cancer mortality) and access to care in specific populations is called cancer health disparities research.
Behavioural research looks at how lifestyle – including what you eat or don’t eat, how physically active you are, where you work and what you do for work and whether you smoke or drink – affects your risk of getting cancer or the risk of a previously treated cancer coming back (called a recurrence).
This type of research also looks at what motivates us to have healthy behaviours and why we don’t always choose them. Behavioural research can help us develop strategies that encourage people to make healthier choices such as not smoking, using sun protection, being physically active and not drinking large amounts of alcohol.
Psychosocial research looks at the emotional, or psychological, and social impact that the disease has on people with cancer, their families and their caregivers. It studies the best ways to support these people. Psychosocial researchers also study how to make sure people with cancer, survivors and their families enjoy the best quality of life possible.
Survivorship research looks at how cancer affects people after treatment has ended, throughout their lives. The number of people surviving cancer in Canada continues to grow – how can we support them better? For example, one area of survivorship research studies the late side effects and complications of treatment. Such research looks at the best way to treat or prevent late side effects and may also compare the long-term side effects of new treatments with past treatments. New treatments may cause different long-term problems.
Improving the long-term health of survivors of childhood cancer is a specialty area in this field of research. Survivors of childhood cancer live with the effects of cancer for a long time and they may face challenges that adult survivors don’t have to face. The treatment that saved their life as a child may affect their ability to grow, to learn or to have children in future. It also may put them at risk of a second cancer when they’re adults.
Pain and symptom management research
Pain and symptom management research focuses on understanding the best ways to relieve symptoms and cope with the stress of a serious illness. It aims to improve quality of life for people with cancer and their families. Pain and symptom management research is also called palliative care research.
End-of-life research aims to understand end-of-life issues better and to improve the quality of death for people with cancer and their families.
The basic biological unit of heredity passed from parents to a child. Genes are pieces of DNA and determine a particular characteristic of an individual.