Many types of drug therapies are used to treat cancer. As well as chemotherapy, these include targeted therapy, immunotherapy and hormone therapy. Together they are known as anticancer drug treatments or systemic anticancer therapy.

The different drug therapies work in different ways to destroy cancer cells. These other drug therapies may be used before or after chemotherapy, surgery or radiation therapy. You may have one drug or a combination of drugs.

This approach often makes treatment more effective and reduces the chance of cancer cells becoming resistant to a particular drug.

Which drug therapy is right for me?

To work out if particular drug therapies are an option for you, your cancer specialist will suggest you have tests to look for gene changes or other features in the cells. The results will help your doctor decide which drug therapy is more likely to work for you.

They will also consider:

• the type and stage of cancer
• your response to previous treatments
• your future treatment options, and
• your overall health.

Drug therapies work for some people, but they don’t work for everyone. Sometimes cancer cells can stop responding to a drug therapy even if it worked at first. In this case, your doctor may prescribe different drugs.

To help more people access other drug therapies, researchers are trying to understand why some people’s cancers respond better than others. Some of these drug therapies are part of standard treatment, while others are being tested in clinical trials.

In most cases, drug therapies such as targeted therapy and immunotherapy are used to treat advanced cancer. This is cancer that has spread or come back after the initial treatment.

Like chemotherapy, targeted therapy and immunotherapy have treatment protocols. You can find these at eviQ Cancer Treatments Online.

Targeted therapy

This drug therapy targets specific features of cancer cells, known as the molecular target, to stop the cancer cell from growing and spreading. The drug will only be given if the cancer cells have the target.

There are many different types of targeted therapy drugs. They are grouped together depending on how they work. These groups include monoclonal antibodies and small-molecule inhibitors.

• Monoclonal antibodies are a manufactured version of natural antibodies made by the body to fight infections. Examples include angiogenesis inhibitors such as bevacizumab.
• Small molecule inhibitors block certain proteins that tell cancer cells to grow. Examples include tyrosine kinase inhibitors (TKIs) such as imatinib and dasatinib, and PARP inhibitors such as olaparib.

Targeted therapy drugs can interact with many common medicines and cause potentially harmful side effects. Tell your doctor if you are taking any other medicines or supplements so they can check for any known problems.

In Australia, targeted therapy drugs are now available for a range of cancers, including:

• blood cancers such as leukaemia and lymphoma
• common cancers such as bowel, breast, lung and melanoma; and
• other cancers such as cervical, head and neck, kidney, liver, ovarian, pancreatic, sarcoma, stomach and thyroid.

For many of these cancers, targeted therapy is available only when the cancer is advanced. For some types, it is also available for early-stage cancer.

Targeted therapy may be given as tablets or capsules that you swallow, intravenously into a vein or as an injection under the skin.

Side effects

“Once treatment was finished, it was quite daunting and I was fearful that the cancer would come back somewhere. Eight years later, it hasn’t come back, which is fantastic.” Pete

Immunotherapy

This drug therapy uses the body’s own immune system to attack cancer cells. There are several different types of immunotherapy, and each works differently.

• Checkpoint inhibitors are the most common. Checkpoint inhibitors remove barriers that stop the immune system from finding and attacking cancer. Examples include pembrolizumab, nivolumab, ipilimumab and atezolizumab.
• Other types stimulate the immune system to help it work better against cancer. Examples include imiquimod.

Immunotherapy using checkpoint inhibitors is available for some types of cancer, including bladder cancer, head and neck cancer, lymphoma, kidney cancer, liver cancer, lung cancer, melanoma and Merkel cell carcinoma.

It is most often given when cancer has come back after the initial treatment (advanced cancer). For some cancer types, it may be available as part of the first treatment plan.

Side effects

Hormone therapy

Hormones are substances that are produced naturally in the body and affect how the body works. Some cancers use hormones to grow. This means the cancer is hormone dependent.

Hormone therapy may also be called hormone-blocking therapy, endocrine therapy or androgen deprivation therapy. The aim of hormone therapy is to lower the amount of hormones the tumour receives.

This can help reduce the size and slow down the spread of the cancer. It can also reduce the risk of the cancer returning after treatment. Common cancers that can be treated with hormone therapy include:

• breast cancer – often depends on the hormone oestrogen to grow; drugs include tamoxifen and aromatase inhibitors such as anastrozole, exemestane, letrozole
• prostate cancer – depends on the hormone testosterone to grow; the most common drug used is goserelin
• uterine cancer – depends on progesterone to grow; drugs include medroxyprogesterone.

Hormone therapy can be given as tablets, injections or through a device placed in the uterus. It can be used for a short time or long term.

How long you have hormone therapy depends on the aim of the treatment, how the cancer responds and any side effects you have.

Side effects