Cancer describes more than 200 diseases that can affect any part of the body. Their common factor is the rapid creation of abnormal cells which can spread to other parts of the body, a process called metastisis.

When cancer is diagnosed, an individualized treatment plan is usually developed based on factors such as the type, location, size and stage of disease and the person's general health.

People with cancer are often treated by a team of specialists that may include surgeons, medical oncologists, radiation oncologists and other medical professionals.

The goal of treatment is to destroy the cancer while doing as little harm as possible to normal tissue. Among the usual treatments are surgery, radiation therapy, chemotherapy, biological therapy (or immunotherapy) and bone marrow and stem cell transplantation. These treatment methods are sometimes used alone and sometimes in combination.

Surgery is most often used to remove the cancer. In some cases, a margin of healthy tissue and nearby lymph nodes may also be removed to try to prevent spread of the cancer. Surgery may be used to treat cancer when it is first diagnosed. When the cancer cannot be cured, surgery is sometimes used to help control the disease and alleviate symptoms.

Radiation therapy (Radiotherapy)

Radiation therapy, or radiotherapy, directs high-energy rays at a cancer site to stop cells from growing and dividing. It may be used before surgery to shrink the tumour or after surgery to destroy any remaining cancer cells. In external radiation therapy, a machine beams the rays at the cancer. In some cases, an implant containing a radioactive substance may be inserted into the tumour to deliver a higher dose of radiation than is possible externally.

 For more information, see our Guide to Radiotherapy.

Chemotherapy

Chemotherapy uses anticancer drugs, singly or in combination, to treat cancer. The drugs may be given by mouth or injected into a vein or muscle. Because anti-cancer drugs can reach cancer cells in nearly every part of the body, chemotherapy may be used as a primary treatment for cancers that have spread.

For more information, see our Guide to Chemotherapy.


Biological therapy (Immunotherapy)

Biological therapy, or immunotherapy, uses substances that stimulate the body's immune system to fight the cancer or reduce side effects from treatment. These substances include monoclonal antibodies, interferons, interleukins, tumour necrosis factor and cancer vaccines.

Hormone therapy

Hormone therapy involves depriving cancer cells of hormones they need to grow. Drugs can be given by mouth or injection to block hormone production. Surgery may be done to remove hormone-producing organs. Radiation and chemotherapy can also be used to stop hormone production.

Bone marrow and stem cell transplantation

Bone marrow and stem cell transplantation is a procedure that uses healthy bone marrow or stem cells to replace marrow damaged or destroyed by high-dose chemotherapy or radiation.

Healthy marrow may be extracted from the person before treatment or may come from a donor.

There are three types of transplant: allogeneic, syngeneic and autologous. The source of stem cells chosen depends on the nature of the disease and the kind of donor available as shown in the table below.

The transplant procedure works in the following way:

• Conditioning therapy and/or radiotherapy is given in high doses to kill your disease or genetic disorder. This treatment destroys the ability of your bone marrow to make new stem cells. Stem cells are the source of all new blood cells and are needed for survival.
• Your bone marrow is then “rescued” with the infusion of donor stem cells. Bone marrow is the soft, spongy center of our bones. It contains part of our immune system.
• An additional mechanism involved in the transplant may help to destroy cancer. The immune system contained within the new or donor stem cells seems to be able to recognize the patient’s cancer cells as foreign and attack them. This is called the graft vs leukemia effect.
• Chemotherapy and radiotherapy also destroy the ability to reject new stem cells.