Cancer is not just one disease but many diseases. There are more than 100 different types of cancer. Most cancers are named for where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the cancer type and how advanced it is. Most treatment plans may include surgery, radiation, and/or chemotherapy. Some may involve hormone therapy, immunotherapy or other types of biological therapy, or stem cell transplantation.

Radiation Therapy

Also called: Brachytherapy, Radiotherapy

Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from spreading. About half of all cancer patients receive it. The radiation may be external, from special machines, or internal, from radioactive substances that a doctor places inside your body. The type of radiation therapy you receive depends on many factors, including:

• The type of cancer
• The size of the cancer
• Cancer's location in the body
• How close the cancer is to normal tissues that are sensitive to radiation
• How far into the body the radiation needs to travel
• Your general health and medical history
• Whether you will have other types of cancer treatment
• Other factors, such as your age and other medical conditions

Radiation therapy can damage normal cells as well as cancer cells. Treatment must be carefully planned to minimize side effects. Common side effects include skin changes and fatigue. Other side effects depend on the part of your body being treated.

Cancer Immunotherapy

Immunotherapy is a cancer treatment that helps your immune system fight cancer. It is a type of biological therapy. Biological therapy uses substances that are made from living organisms, or versions of these substances that are made in a lab.

Doctors don't yet use immunotherapy as often as other cancer treatments, such as surgery, chemotherapy, and radiation therapy. But they do use immunotherapy for some types of cancer, and researchers are doing clinical trials to see whether it also works for other types.

When you have cancer, some of your cells begin to multiply without stopping. They spread into the surrounding tissues. One reason that the cancer cells can keep growing and spreading is that they can hide from your immune system. Some immunotherapies can "mark" your cancer cells. This makes it easier for your immune system to find and destroy the cells. It is a type of targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells. Other types of immunotherapies work by boosting your immune system to work better against cancer.

You could get immunotherapy intravenously (by IV), in pills or capsules, or cream for your skin. For bladder cancer, they might place it directly into your bladder. You may have treatment every day, week, or month. Some immunotherapies are given in cycles. It depends on your type of cancer, how advanced it is, the type of immunotherapy you get, and how well it is working.

You may have side effects. The most common side effects are skin reactions at the needle site if you get it by IV. Other side effects may include flu-like symptoms, or rarely, severe reactions.

Stem Cells

Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair system for the body. There are two main types of stem cells: embryonic stem cells and adult stem cells.

Stem cells are different from other cells in the body in three ways:

• They can divide and renew themselves over a long time
• They are unspecialized, so they cannot do specific functions in the body
• They have the potential to become specialized cells, such as muscle cells, blood cells, and brain cells

Doctors and scientists are excited about stem cells because they could help in many different areas of health and medical research. Studying stem cells may help explain how serious conditions such as birth defects and cancer come about. Stem cells may one day be used to make cells and tissues for the therapy of many diseases. Examples include Parkinson's disease, Alzheimer's disease, spinal cord injury, heart disease, diabetes, and arthritis.