Be Smart About the Sun

What is Melanoma/ Skin Cancer?

Anatomy of the skin, showing the epidermis, dermis, and subcutaneous tissue. Melanocytes are in the layer of basal cells at the deepest part of the epidermis. Photo from National Cancer Institute.

Melanoma is a cancer that begins in specific type of skin cell. The skin is the body’s largest organ, and it helps protect against, heat, sunlight, injury and infection. Your skin helps control body temperature as well as stores water, fat and vitamin D. With several layers, the epidermis and dermis are the two main ones.

The epidermis is made up of three cell types:

• Squamous cells – thin, flat cells making up majority of the epidermis
• Basal cells – round cells under the squamous cells
• Melanocytes – found throughout the lower part of epidermis and make melanin (the pigment giving skins its natural color)

The dermis contains blood and lymph vessels, hair follicles and glands.

The most common type of skin cancer is squamous cell carcinoma, which forms in the squamous cells and basal cell carcinoma. The basal cell carcinoma forms in the basal cells.  Squamous cell carcinoma and basal cell carcinoma are also called non-melanoma skin cancers and are the most common type of skin cancer in the United States. These non-melanoma skin cancers can usually be cured. Melanoma forms in the melanocytes and is a less common type of skin cancer. Melanoma is harder to cure because it tends to spread to nearby tissues and other parts of the body.

Skin cancer can occur anywhere on the body. It is most common in skin that is most often exposed to sunlight such as the face, neck, hands and arms.

Prevention

Not all melanoma can be prevented, but there are ways to help reduce your risk.

• Limit ultraviolet (UV) exposure
• Identify abnormal moles and have them removed
• Genetic counseling and testing

Early Detection

Many times, melanoma can be detected early. When it is found early, it is more likely that your cancer will be curable. Self-exams are important. You should check your skin once a month to see if there are any new moles or changes in moles already present. Perform these self-exams in a well-lit room with a hand-held mirror to look at those hard to see places, such as the backs of your thighs. Being examined for skin cancer by a health care professional should also be a part of your routine checkup.

Non-melanoma and Melanoma Cancer Risk Factors

Non-melanoma skin cancer

• Being exposed to natural or artificial sunlight (tanning beds) over long periods of time
• Fair skin, freckling and light hair
• Having actinic keratosis
• Past radiation treatment
• Weak immune system
• Men have a higher rate of non-melanoma skin cancer

Melanoma skin cancer

• Ultraviolet (UV) light exposure
• Moles
• Fair skin, freckling and light hair
• Family history of melanoma
• Personal history of melanoma
• Immune suppression
• Age
• Men have a higher rate of melanoma than women in the U.S.
• Xeroderma pigmentosum (a rare, inherited condition resulting from a defect in an enzyme that normally repairs damage to DNA)

Facing Diagnosis

If you find an abnormal area of skin that raises your suspicion for skin cancer, medical exams and tests may be used to indicate if it is melanoma, non-melanoma skin cancer or some other skin condition. If melanoma is found, you will undergo other tests to determine if the cancer has spread to other areas of the body. The following steps are those that you will take when facing a possible diagnosis:

• Meeting with your health care provider to discuss medical history and have a physical exam
• A biopsy is taken
• Biopsies of melanoma may be taken in order to determine if the cancer has spread
• Imaging tests are used to look for the possible spread of melanoma to lymph nodes or other organs in the body.

If you would like more information, please visit our Patient and Family Resource Center in The Vanderbilt Clinic.
Sources: National Cancer Institute and American Cancer Society