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What You Need To Know About™ Skin Cancer
    Posted: 07/30/2009
Understanding Skin Cancer

Skin cancer begins in cells, the building blocks that make up the skin. Normally, skin cells grow and divide to form new cells. Every day skin cells grow old and die, and new cells take their place.

Sometimes, this orderly process goes wrong. New cells form when the skin does not need them, and old or damaged cells do not die when they should. These extra cells can form a mass of tissue called a growth or tumor.

Growths or tumors can be benign or malignant:

  • Benign growths are not cancer:
    • Benign growths are rarely life-threatening.
    • Generally, benign growths can be removed. They usually do not grow back.
    • Cells from benign growths do not invade the tissues around them.
    • Cells from benign growths do not spread to other parts of the body.
  • Malignant growths are cancer:
    • Malignant growths are generally more serious than benign growths. They may be life-threatening. However, the two most common types of skin cancer cause only about one out of every thousand deaths from cancer.
    • Malignant growths often can be removed. But sometimes they grow back.
    • Cells from malignant growths can invade and damage nearby tissues and organs.
    • Cells from some malignant growths can spread to other parts of the body. The spread of cancer is called metastasis.

Types of Skin Cancer

Skin cancers are named for the type of cells that become cancerous.

The two most common types of skin cancer are basal cell cancer and squamous cell cancer. These cancers usually form on the head, face, neck, hands, and arms. These areas are exposed to the sun. But skin cancer can occur anywhere.

  • Basal cell skin cancer grows slowly. It usually occurs on areas of the skin that have been in the sun. It is most common on the face. Basal cell cancer rarely spreads to other parts of the body.
  • Squamous cell skin cancer also occurs on parts of the skin that have been in the sun. But it also may be in places that are not in the sun. Squamous cell cancer sometimes spreads to lymph nodes and organs inside the body.

If skin cancer spreads from its original place to another part of the body, the new growth has the same kind of abnormal cells and the same name as the primary growth. It is still called skin cancer.



Dictionary Terms

basal cell carcinoma (BAY-sul SEL KAR-sih-NOH-muh)
A type of skin cancer that arises from the basal cells, small round cells found in the lower part (or base) of the epidermis, the outer layer of the skin.
benign (beh-NINE)
Not cancerous. Benign tumors may grow larger but do not spread to other parts of the body. Also called nonmalignant.
lymph node (limf node)
A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.
malignant (muh-LIG-nunt)
Cancerous. Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body.
metastasis (meh-TAS-tuh-sis)
The spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor. The plural form of metastasis is metastases (meh-TAS-tuh-SEEZ).
primary tumor
The original tumor.
squamous cell carcinoma (SKWAY-mus sel KAR-sih-NOH-muh)
Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. Squamous cells are found in the tissue that forms the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts. Also called epidermoid carcinoma.
tissue (TISH-oo)
A group or layer of cells that work together to perform a specific function.
tumor (TOO-mer)
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.