Medical oncology

Medical oncology is a branch of medicine that cares for patients with cancer. A medical oncologist is a specialist doctor who uses chemotherapy and other medications to manage cancer. These medications aim to kill cancer cells, prevent cancer from recurring, or control the cancer to reduce its symptoms.

Cancer management

Treating cancer is extremely complex.  It often involves a team of medical specialists working together to design the best course of action based on the latest scientific evidence.  As the exact nature of the cancer varies from person to person, your treatment plan is personalised to your specific condition. It may involve one or more forms of treatment and it is highly likely that you will consult with a surgeon, a medical oncologist and perhaps a radiation oncologist. Your specialist doctors will explain why a certain treatment approach is being recommended and what it involves.  It’s important to ask questions, particularly if there is something you don’t quite understand or are unsure about.  Having a friend, family member or carer accompany you to your appointments can also be helpful as there is usually a lot of information to take in.

Treating cancer with medicines

When you think of medicines to treat cancer, the word ‘chemotherapy’ or ‘chemo’ probably springs to mind.  Chemotherapy is generally associated with cancer killing drugs that are injected into a vein (called an intravenous infusion), but some chemotherapy medications can also be given as oral tablets.

Chemotherapy may be offered as a stand-alone treatment for cancer, or as part of a combined approach together with surgery and/or radiation therapy.  Chemotherapy can also be used to help control cancer when a cure may not be possible.

Many different medications exist to treat cancer. Some work across multiple cancer types, whereas others are far more specific and may only be effective for one type of cancer.


Traditional or standard chemotherapy works by disrupting the cell cycle. Each time a new cell forms it goes through a series of phases in order to become mature.  Traditional chemotherapy drugs target the different phases of the cell cycle. By disrupting or stopping a particular phase, a cancerous cell can no longer mature and divide and ultimately dies.

Find out more on chemotherapy

Find out more about chemotherapy, including how it works and who it’s for.

Hormone therapy

Some cancers make use of your body’s own hormones to grow and multiply.  These cancers are known as ‘hormone dependent’ cancers and include some types of breast, uterine and prostate cancers.  Hormone therapy uses drugs to block the body’s own hormones, e.g.  testosterone in men and oestrogen in women.  By stopping or lowering the amount of hormones the tumour receives, the growth of the cancer can be slowed.


Your immune system is designed to protect your body from threats such as infections, toxins and abnormal cell development (cancer).  Your immune system usually prevents cancers from occurring, but sometimes it is not strong enough to combat abnormal cell growth.  Immunotherapy drugs boost or improve how your own body’s immune system works to fight cancer.  Immunotherapy drugs work in different ways and include:

  • Checkpoint inhibitors: These drugs take the ‘brakes’ off the immune system, which helps it to then recognise and attack cancer cells.  e.g. pembrolizumab, nivolumab, atezolizumab, durvalumab, ipilimumab.
  • Chimeric antigen receptor (CAR) T-cell therapy: T-cells from a patient’s blood are mixed with a special virus that makes the T-cells learn how to attach to tumour cells.  These cells are then given back to the patient so they can find, attach to, and kill the cancer.
  • Cytokines: Cytokines are small proteins that carry messages between cells.  They are used to stimulate the immune cells to attack cancer.  e.g. interferon and interleukin.
  • Immunomodulators: Boost parts of the immune system to treat certain types of cancer. e.g. thalidomide, lenalidomide.
  • Cancer vaccines: Vaccines are being researched and developed with the aim of preventing or treating cancer through an immune response.  Sipuleucel-T is a vaccine that has been approved for advanced prostate cancer.
  • Oncolytic viruses:  Research into how viruses may be used to kill cancer is ongoing.  By modifying viruses in the laboratory, it is hoped that they will be able to target, infect and kill certain cancerous cells.

Targeted therapies

Targeted therapies do not work in the same way as traditional chemotherapy even though they are technically considered to be a form of chemotherapy. As the name suggests, targeted therapies work by finding a specific target on cancerous cells that they can attack or block to stop the cells from making new cancer cells.  If your cancer type is known to have a target, it will be tested at the time of your biopsy or surgery to see if the target is present.  Assuming it is, a targeted therapy may form part of your treatment plan. As these drugs have a targeted action to the cancer cell, the damage to normal cells is usually reduced, but this does not mean that targeted therapies are free of side-effects.

Some types of targeted therapies include but are not limited to:

  • Angiogenesis inhibitors:  Block the formation of new blood vessels to the tumour so that the tumour is deprived of nutrients. e.g. bevacizumab.
  • Monoclonal antibodies:  Deliver molecules to the target on the cancer cell which then interfere with the cell’s ability to signal and divide. e.g. trastuzumab, pertuzumab, cetuximab, alemtuzumab.
  • Signal transduction inhibitors: Block the signals passed from one molecule to another inside a cell.  By blocking the signals, the cell cannot function properly and its ability to divide is affected.  e.g. lapatinib, gefitinib, erlotinib, sunitinib, sorafenib.

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