Research in chemotherapy
Chemotherapy is a term commonly used to describe a variety of drugs used to treat cancer. Chemotherapy is usually a systemic therapy. This means that the drugs travel through the bloodstream to reach cancer cells all over the body, including those that may have broken away from the primary tumour. Chemotherapy is also sometimes called cytotoxic therapy.
Researchers are constantly looking for ways to improve chemotherapy treatment. They are developing new drugs and trying new combinations of existing drugs to find the best combinations. They are also looking for new ways to give drugs to make them easier to take or more convenient. For example, researchers have developed drugs in oral form (as pills) that used to be given through a needle in a vein (intravenously).
Drugs to overcome drug resistance
Some tumours can develop resistance to chemotherapy. One example of how they do this is by pumping chemotherapy drugs out of the cancer cells. If researchers can find out how to stop the pumps inside of cancer cells, chemotherapy may remain in the cancer cells longer and work better.
Improving schedules and doses
Researchers are looking for ways to make chemotherapy drugs work better and with fewer side effects. Examples of this research include:
- trying to find out if smaller amounts of drugs can be given over longer periods of time
- seeing if patients can take breaks from chemotherapy (called treatment or drug holidays) without affecting how well the treatment works
- reducing the time between doses of chemotherapy (called dose-dense chemotherapy) and studying very high doses (called high-dose chemotherapy) to see if they work better to treat cancers that don’t respond to standard doses
Combining chemotherapy and radiation therapy
Researchers continue to study chemotherapy given during the same time period as radiation therapy to treat many types of cancer. This is called chemoradiation. Some research is looking at different chemotherapy drugs or combinations of drugs given with radiation therapy. Other research is trying to find out if chemoradiation is an effective way to treat certain types of cancer that haven’t been treated this way before.
Nanotechnology to deliver chemotherapy
Researchers are using nanotechnology to deliver chemotherapy drugs. Nanotechnology is a branch of technology done on a very small scale in the measurement of nanometres. Atoms, molecules and other tiny particles are measured in nanometres.
Tiny particles (called nanoparticles) can be used to deliver chemotherapy drugs directly to the tumour. Researchers are testing nanotechnology to deliver chemotherapy in a couple of ways:
- Since blood vessels inside of cancerous tumours are leaky, they allow the nanoparticles to easily pass into the tumour where they build up and deliver the chemotherapy drug. But since the particles don’t pass easily through blood vessels in healthy tissues of the body, this approach helps to reduce side effects.
- Some nanoparticles can bind directly to cancer cells by targeting certain receptors (molecules) found on their surface. The nanoparticle carrying the chemotherapy drug can then be absorbed by the cancer cell.
We need more research to be sure, but chemotherapy using nanotechnology seems to have several advantages over standard chemotherapy. Nanotechnology:
- helps prevent chemotherapy drugs from breaking down before they reach cancer cells
- allows the drugs to get better or more easily absorbed into cancer cells so tumours get smaller and smaller more quickly
- allows doctors to use higher doses of chemotherapy drugs but with fewer side effects because healthy cells don’t get as damaged
What’s the lifetime risk of getting cancer?
The latest Canadian Cancer Statistics report shows about half of Canadians are expected to be diagnosed with cancer in their lifetime.