Alternate Names: Melanoma

Causes and Risks:

Malignant melanoma is the most deadly form of skin cancer. While less common than other types of skin cancer, the incidence of malignant melanoma is steadily increasing without a clear understanding of why. It is the leading cause of death from skin disease. In the year 2000, almost 50,000 cases of malignant melanoma were expected. The average lifetime risk of developing melanoma in the United States is approximately 1 in 85. The risk of melanoma increases with age, but frequently effects young, otherwise healthy people. Melanoma is the number one cause of cancer death in women aged 25 to 30.

Malignant melanoma involves cancerous changes to the skin cells that produce the skin’s pigment, melanin. Melanoma may appear on normal skin or arise from a nevius (moles) or other lesion that has changed in appearance. Some congenital nevi may develop into melanomas. Spitz Nevi are benign lesions in children that do not develop into melanoma, but can be sometimes difficult to distinguish from melanoma.

There are 4 major types of melanoma:

• Superficial spreading melanoma is the most common type of melanoma, accouting for approximately 70% of cases. It is usually flat and irregular in shape and color with varying shades of black and brown. It may occur at any age or site and is most common in Caucasians.
• Nodular melanoma usually starts as a raised lesion that is dark black-blue or bluish-red, however some can lack color. Nodular melanomas account for approximately 15% of cases.
• Lentigo maligna melanoma occurs in about 5% of cases, usually in the elderly. It is most common in sun damaged skin on the face, neck, and arms. The lesions are usually large, flat, and tan with intermixed areas of brown.
• Acral lentiginous melanoma is the least common form of melanoma. It usually occurs on the palms, soles, or under the nails. It is more common in African Americans.

Melanoma is related to sun exposure, particularly to sunburns during childhood, and is most common in those with fair skin, blue eyes, and light hair.

Prevention: Minimize sun exposure. Protect skin from the sun: wear protective clothing such as hats, long sleeved shirts, long skirts or pants. Sunlight is most intense at mid-day, so try to avoid exposure during these hours. Use high quality sunscreens, preferably with SPF (sun protection factor) ratings of at least 15. Apply sunscreen at least one-half hour before exposure, and reapply frequently. Use sunscreen for winter exposure also.

Examine the skin regularly for development of suspicious growths or changes in an existing skin lesion. A new growth that ulcerates or is slow to heal is suspicious. Suspicious changes in existing growths include change in color, size, texture, appearance, or development of pain, inflammation, bleeding or itching. A lesion that is asymmetrical, has irregular or diffuse borders, has multiple colors mixed in one lesion, or is larger than 6 millimeters in diameter is suspicious.

Symptoms: ALL FORMS

• skin lesion or growth
  • usually a papule (raised) or, less likely, a macule (flat)
  • color varying (brown, black, red or bluish)
  • mixture of colors in one lesion
  • irregular borders, often asymmetrical
  • a change in appearance over time in pigmented skin lesion
  • bleeding from a skin growth

• ABCDs

• Asymmetry: one half of the lesion is different than the other half
• Borders: irregular borders
• Color: varied from one area to another with shades of tan, brown or black and sometimes white, red, blue
• Diameter: usually (but not always) larger than 6mm in size (diameter of a pencil eraser)

SUPERFICIAL SPREADING MELANOMA

• possible ulceration and lack of healing
• ABCDs

NODULAR MELANOMA

• nodules, bumps
• color usually ranges from dark black-blue to bluish-red
• possible ulceration and lack of healing

ACRAL LENTIGINOUS MELANOMA

• skin lesion or growth
  • dark color: usually tan, brown or black
  • usually on the palms, soles or under nails
  • possible ulceration and lack of healing

• skin lesion or growth
  • irregular borders
  • large
  • brownish color with darker speckles
  • usually on skin that has been overexposed to the sun

Signs and Tests: The appearance of the skin lesion may indicate malignant melanoma.

A skin biopsy and examination can confirm the diagnosis. An X-ray, CT scan, MRI, or other procedures may be indicated to determine if spreading (metastasis) has occurred.

Treatment:

The goal of treatment is to cure the cancer.

Surgical removal of the tumor, with a margin of normal skin also removed, is usually required. Surgical removal of nearby lymph nodes or a procedure called a "sentinel lymph node biopsy" may accompany removal of the tumor.

For patients with tumors with a depth greater than 4mm or with lymph nodes involved (these tumors have a relatively high risk of recurring elsewhere in the body), inteferon may be recommended following surgery. While the data have been somewhat conflicting, it appears that giving inteferon for one year improves the overall chance of cure by approximately 10%. However, inteferon has many side effects and is a very difficult therapy to tolerate. Patients with high risk melanomas should consider enrolling in clinical trials.

For patients with melanoma that has spread beyond the skin and lymph nodes to other organs (metastatic melanoma), treatment is more difficult. Metastatic melanoma is usually not cureable except in a small percentage of patients (occasionally in patients with isolated metastases, surgical removal of these metastases will result in cure). Treatment is usually directed and shrinking tumor and improving symptoms. Both chemotherapy and use of immunologic agents such as inteferon and interleukin may be used. These patients also should consider enrollment into clinical trials.

Support Groups: The stress of illness can often be helped by joining a support group where members share common experiences and problems. See cancer - support group.

Prognosis: The depth (thickness) of the tumor is the single most important factor in determining prognosis (expected outcome).

The vast majority of malignant melanomas are cured if treated early. The risk of recurrence increases as the depth of the tumor increases and when lymph nodes are involved. When tumor has spread to other organs, the likelihood of cure is small and most patients die of their disease.

Complications:

• spread to deep tissues with damage to structure or function
• metastasis of tumor to other locations within the body

Call your health care provider if symptoms indicate that malignant melanoma may be present; if any existing skin lesion changes in color, size, texture, or appearance; or if you develop pain, inflammation, bleeding or itching of an existing skin lesion.