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What Is Cancer?

Understanding What Cancer Is and How Cancer Develops

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Updated July 01, 2014

What is Cancer?
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If someone asked you to define cancer, could you do it? We all have heard the word "cancer" many times, however very few people understand the disease and how it develops.

Cancer is term that encompasses a complex group of more than 100 different types of cancerous diseases. Cancer can affect just about every organ in the human body. Many people are surprised to learn that cancer can affect parts of the body like eyes and the heart.

Each type of cancer is unique with its own causes, symptoms, and methods of treatment. Like with all groups of disease, some types of cancer are more common than others. A-Z Index of Types of Cancer

How Does Cancer Develop?

The organs in our body are made up of cells. Cells divide and multiply as the body needs them. When these cells continue multiplying when the body doesn't need them, the result is a mass or growth, also called a tumor.

These growths are considered either benign or malignant. Benign is considered non-cancerous and malignant is cancerous. Benign tumors rarely are life threatening and do not spread to other parts of the body. They can often be removed.

Malignant tumors, however, often invade nearby tissue and organs, spreading the disease.
 

How Does Cancer Spread to Other Parts of the Body?

The cells within malignant tumors have the ability to invade neighboring tissues and organs, thus spreading the disease. It is also possible for cancerous cells to break free from the tumor site and enter the bloodstream, spreading the disease to other organs. This process of spreading is called metastasis.

When cancer has metastasized and has affected other areas of the body, the disease is still referred to the organ of origination. For example, if cervical cancer spreads to the lungs, it is still called cervical cancer, not lung cancer.

Although most cancers develop and spread this way -- via an organ - blood cancer like leukemia do not. They affect the blood and the organs that form blood and then invade nearby tissues.

Cancer Symptoms

Symptoms of cancer vary based on the type of cancer. As cancer progresses to an advanced stage, common symptoms can include weight loss, fever, and fatigue. These are very non-specific symptoms that are more likely related to other less serious illnesses than cancer.

Treatment of Cancer

There are four standard methods of treatment for cancer: surgery, chemotherapy, radiation therapy, and immunotherapy/biologic therapy. When initially diagnosed with cancer, a cancer specialist (called an oncologist) will provide the patient with cancer treatment options. He or she will recommend the best treatment plan based on the type of cancer, how far it has spread, and other important factors like age and general health.

Ultimately, it is the patient who makes the treatment decisions based on doctor's recommendations, possible second opinions, and other information gathered from qualified professionals.

Cancer Prevention

Most people don't realize that cancer is preventable in many cases. Learning what causes cancer and what the risk factors are is the first step in cancer prevention. Many cancer risk factors can be avoided, thus reducing the likelihood of developing cancer. Of course, some cancer risks like genetics cannot be avoided.

Smoking is the most significant cancer risk factor that we can reduce. It is responsible for not only lung cancer, but many other types of cancer. One of the best ways to prevent cancer is to quit smoking or never start. As soon as you quit, and it's never too late, your body reaps the benefits of being tobacco-free. More Cancer Prevention Tips

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