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Cancer

What is cancer?

Cancer is not just one disease but many diseases. Cancer begins in your cells, which are the building blocks of your body. Usually, your body forms new cells as needed, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should. These extra cells can form a mass called a tumor.

Tumors can be benign or malignant. Benign tumors aren't cancer, while malignant ones are. Cells from malignant tumors can invade nearby tissues. They can also break away and spread to other parts of your body. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the type of cancer and how advanced it is.

What are the types of cancer?

There are more than 100 different types of cancer. Cancer can start almost anywhere in your body. Most cancers are named for where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast.

Cancer may also be described by the type of cell that formed it, such as sarcoma if cancer begins in your bone and soft tissue. Carcinoma is the most common type of cancer. It is formed by epithelial cells, the cells that cover the inside and outside surfaces of your body.

How does cancer develop?

Cancer is a genetic disease. That means changes in your genes cause it. Changes in your genes are also called gene variants or mutations. Genes are parts of DNA in your cells that you inherit from your parents. However, only some cancers are caused by genes passed down from your parents.

Genetic changes can occur to your genes over your lifetime that affect how your cells function. Usually, your body gets rid of damaged cells before they turn cancerous, but this ability goes down as you age. Other factors that may affect your risk of developing cancer can include:

What are the symptoms of cancer?

Cancer symptoms depend on the type of cancer. For example, some of the symptoms that cancer may cause can include:

Cancer may cause various symptoms but often doesn't cause pain. Don't wait until you're having pain before seeing your health care provider. See your provider if you have symptoms that don't get better in a few weeks.

How is cancer diagnosed?

There is no single test that can diagnose cancer. The tests ordered are usually based on your symptoms. Your provider may:

To find out if you have cancer, your provider may order a biopsy. A biopsy is the procedure of removing and examining tissue, cells, or fluids from your body.

What are the treatments for cancer?

Treatment depends on the type of cancer 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.

Can cancer be prevented?

It's usually not possible to know exactly why cancer develops in some people but not others. There are some things that you can't control which may increase or decrease your risk of getting cancer, such as inheriting certain genes or your age. But some lifestyle habits may increase your risk of certain types of cancer. Avoid or reduce lifestyle habits such as:

NIH: National Cancer Institute

Lung Cancer

What is lung cancer?

Lung cancer is cancer that forms in tissues of the lung, usually in the cells that line the air passages. It is the leading cause of cancer death in both men and women.

There are two main types: small cell lung cancer and non-small cell lung cancer. These two types grow differently and are treated differently. Non-small cell lung cancer is the more common type.

Who more likely to develop lung cancer?

Anyone can develop lung cancer, but certain factors raise your risk of getting it:

What are the symptoms of lung cancer?

Lung cancer may not cause any signs or symptoms until the cancer is advanced. Sometimes the cancer is found during a chest x-ray done for another condition.

The symptoms of lung cancer may include:

How is lung cancer diagnosed?

To find out if you have lung cancer, your health care provider:

If you do have lung cancer, your provider will do other tests to find out if it has spread through the lungs, lymph nodes, and the rest of the body. This is called staging. Knowing the type and stage of lung cancer you have helps your provider decide what kind of treatment you need.

If you have small-cell lung cancer, your provider may also do genetic testing to look for certain gene changes (variants) in your cancer cells. The results of the testing may help guide treatment.

What are the treatments for lung cancer?

For most patients with lung cancer, current treatments do not cure the cancer.

Your treatment will depend on which type of lung cancer you have, how far it has spread, your overall health, and other factors. You may get more than one type of treatment.

The treatments for small cell lung cancer may include:

The treatments for non-small cell lung cancer may include:

Can lung cancer be prevented?

Avoiding the risk factors may help prevent lung cancer. For example, you can:

NIH: National Cancer Institute

Skin Cancer

Skin cancer is the most common form of cancer in the United States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common.

Anyone can get skin cancer, but it is more common in people who :

You should have your doctor check any suspicious skin markings and any changes in the way your skin looks. Treatment is more likely to work well when cancer is found early. If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments include surgery, radiation therapy, chemotherapy, photodynamic therapy (PDT), and biologic therapy. PDT uses a drug and a type of laser light to kill cancer cells. Biologic therapy boosts your body's own ability to fight cancer.

NIH: National Cancer Institute

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