Melanoma is the most serious type of skin cancer. It begins in skin cells called melanocytes, which produce melanin, the pigment that gives skin its natural color. When skin is exposed to ultraviolet light from the sun or artificial sources (such as tanning beds), melanocytes produce more pigment causing the skin to darken.

If the skin receives too much ultraviolet light, the melanocytes may begin to grow abnormally and become cancerous. This condition is called melanoma. Melanomas can appear anywhere on the skin.

The chance of getting melanoma increases as you get older, but individuals of any age can develop melanoma.

If melanoma is found and treated in its early stages, the chances of recovery are good. If it is not found early, melanoma can grow deeper into the skin, spread to other parts of the body, and produce malignant tumors in different organs such as lungs, liver, etc.

• Superficial spreading melanoma. The most common form of skin melanoma in Caucasians. It tends to occur on sun-exposed skin, especially on the backs of men and lower limbs of women. The average age at diagnosis is between 50 and 60 years of age.
• Nodular melanoma. The most aggressive form of melanoma. It grows very fast and deep in the skin in a vertical direction from the surface of the skin. It initially presents as a small black or pink (amelanotic) nodule that enlarges and tends to bleed.
• Acral lentiginous melanoma (also known as subungual melanoma). Does not appear to be linked to sun exposure. It is typically observed on the palms of the hands, soles of the feet, and under the nails. This is the most common form of melanoma in Asians and Blacks, but it can also occur in Caucasians. The average age at diagnosis is between 60 and 70 years of age but it is also observed in younger persons.
• Lentigo maligna. Consists of cancer cells but does not display an invasive growth in the skin. It typically progresses very slowly and can remain in a non-invasive (superficial) form for years. The development of a bumpy surface on the skin marks the transition to true melanoma. It is normally found in the elderly on skin areas with high levels of sun exposure such as the face and forearms.

Melanoma is often painless and may exhibit the following signs:

• A change in the shape, color, or size of an existing mole
• The appearance as a new growth or mole on the skin

When performing self examinations, one should keep in mind the ABCD guide regarding suspicious moles and growths on the skin:

• Asymmetry—the two halves of an existing growth or mole are shaped differently.
• Border irregular—the edges of the growth or mole are ragged or uneven.
• Color varied—melanomas may be multi-colored, e.g., black with brown and tan, or even speckled with a number of other colors.
• Diameter—measured across, the diameter of the growth or mole is larger than a pencil eraser.

A biopsy (removal of an area of the suspicious growth) is the only certain way of diagnosing melanoma. Once the tissue sample is removed, a specialist examines it for cancer cells under a microscope.

The type of biopsy depends on the size of the skin growth and its location on the body. Several types of biopsy can be done when the doctor suspects a patient may have melanoma:

• An excisional biopsy cuts away the growth and some of the normal surrounding skin
• An incisional biopsy, or core biopsy, removes only a sample of the growth
• A punch biopsy removes a small, cylindrical shaped sample of skin
• A saucerization biopsy lifts the entire lesion from underneath
• A fine-needle aspiration biopsy is done with a very thin needle inserted in lymph nodes or an internal organ to collect cancer cells and determine if the melanoma has spread from the skin to these organs