Melanoma, also known as malignant melanoma and cutaneous melanoma, is a cancer that usually appears in a certain type of skin cells called melanocytes, the cells that color the skin.

Melanomas can be classified into four major categories: Superficial spreading melanoma and lentigo maligna melanoma, which remain superficial for an extended time; acral lentiginous melanoma, which develops on the soles or palms; and nodular melanoma, which tends to be invasive.

The precise cause of all melanomas is not yet fully determined, but the risk of developing melanoma can be traced to exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds. Factors which could contribute to increasing the risk of having melanoma could include a family or personal history of melanoma and other cancers, and having many moles.

This kind of cancer occurs when mutations triggered by UV radiation causes DNA damage to skin cells that fail to repair; these mutations encourage rapid multiplying of skin cells. Melanoma usually occurs in five stages.

The first noticed signs and symptoms of melanoma are changing of the appearance of already existing mole and emerging of a new pigmented growth on the skin.

Different features are used to distinguish whether the noticed growth is melanoma or a mole; these features include asymmetry, border, color, diameter, and evolving of the noticed growth.

An excisional biopsy can be used to diagnose melanoma and to examine melanoma's thickness. CT scans or other types of X-rays may be conducted to see if the tumor has spread to other regions once melanoma is positively diagnosed.

Removing the melanoma by a surgical procedure might be the only treatment needed for people with early-stage melanomas. Other treatments for melanoma include Lymphadenectomy, immunotherapy, targeted therapy, chemotherapy, and radiation therapy. Other supportive treatment options that may be recommended in case of melanoma include adoptive T-cell therapy, palliative care, and vaccine therapy.

Melanoma has the potential to reach other body parts very quickly.

It remains unclear how melanoma can be prevented completely. There is a variety of measures that can be taken in order to lower the risk of having melanoma. These measures include restricting the exposure to ultraviolet rays, awareness of abnormal moles, and avoidance of weakening of the immune system, if possible.

The annual increase in the incidence rate of melanoma for Caucasians worldwide has been approximately 3–7%. It is extremely rare to detect melanoma among black populations in Africa. However, most cases of melanoma among black populations tend to be of the acral lentiginous subtype. In most cases, melanomas affect men on the back, while in women, it is found mostly on the legs.

Melanoma is a tumor that usually begins in the skin. The cells that color the skin, melanocytes, are the cells where melanoma cancers begin. Most melanomas continue to produce melanin giving the cancer a black or brown color. However, some melanomas cannot produce melanin and appear pink or white.

Melanomas can be classified into four major categories:

• Superficial spreading melanoma: This is the most common type of melanoma. It is seen mostly in young people. This type of melanoma starts at the top layer of the skin as a flat growth irregular in shape and color. This type remains superficial for quite a while before penetrating the deep layers of skin.
• Lentigo maligna: This type has similar features to superficial spreading melanoma in the way that it stays close to the skin surface for a fairly long time. It appears on chronically sun-exposed skin, mostly on the face, arms, ears, and upper trunk as a large, flat, and tan area of abnormal skin. This type of melanoma is seen mostly in the elderly.
• Acral lentiginous melanoma: It is known to spread superficially before penetrating deep into the skin, similar to the first two types. This type is thought to be the most common type of melanoma affecting dark-skinned people. It is characterized by black or brown discoloration under the nails or on the soles of the feet or palms of the hands. This type is able to develop more quickly than superficial spreading melanoma and lentigo maligna.
• Nodular melanoma: This type usually starts as raised area colored black, but sometimes it appears blue, gray, white, brown, red or skin tone. It tends to be invasive at the time it is first diagnosed.

The precise cause of all melanomas is not yet fully determined, but the risk of developing melanoma can be traced to exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds.

Skin damage made by the sun is the main risk factor which can lead to a melanoma. Other factors that could contribute to increasing the risk of having melanoma include:

• A family history of melanoma: If a person’s close blood relative develops melanoma, then the risk of that person is approximately doubled.
• Moles: People with many moles, or moles that are irregular in shape, color or size, are at an increased risk of having melanoma.
• History of cancer: Getting a second melanoma is possible in people who have had a melanoma before. In addition, the risk of melanoma increases if the person had any other type of cancer.
• Place of birth: Relatively pale skinned people born in countries with a hot climate, such as Australia, are at an increased risk of exposure to the sun in their early years of life when the skin is most sensitive, which increases the chance of developing melanoma.
• Using UV emitting machines: These include sunbeds or similar tanning devices that rely on UV rays. People with red hair, freckles, or young people under the age of 20 are more at risk of developing melanoma when using sunbeds and similar machines.
• Weak immune system: A weakened immune system increases the risk of melanoma because the immune system helps fight cancer. The immune system may be weakened by medical conditions, such as HIV, or by using immunosuppressive medications in case of organ transplant, for example.

Melanoma occurs when the DNA of pigment-producing melanocytes in the basal layer of the epidermis is damaged by UV radiation and is not repaired. This damage leads to mutations that encourage rapid multiplying of skin cells to form malignant cancers. Some melanomas develop from moles and can often resemble moles. The stages of melanoma are :

• Stage 0 (in situ): The tumor is limited to the epidermis, the top layer of skin.
• Stage I: Although the tumor has grown thicker, up to 1.0 millimeter, it is still limited to the skin.
• Stage II: The thickness of the tumor is increased and may range from 1.01 millimeters to greater than 4.0 millimeters.
• Stage III: The tumor has reached either nearby skin or nearby lymph nodes.
• Stage IV: The tumor has reached an internal organ, or has spread to lymph nodes or skin distant from the original melanoma.

Usually, the first signs and symptoms of melanoma are the changing of the appearance of already existing mole, or the emerging of a new pigmented or remarkable growth on the skin. Additionally, melanoma can cause the following symptoms:

• Pain, itches, and bleeding.
• A persistent mole that does not heal.
• Swelling outside the border of a mole.
• Pigment in the mole spreads to nearby skin.

To distinguish between melanomas and normal moles, the healthcare provider studies certain features that may help spot a melanoma. These features are abbreviated as ABCDE and include:

• Asymmetry: Often, melanoma is seen as an uneven and asymmetrical growth, different from moles which are seemingly round and even.
• Border: Melanoma is known to have blurred, ragged, or notched borders or edges. Moles usually have a smooth, well-defined border.
• Color: Different shades or colors is a main feature of melanoma. Therefore, there may be 2-3 shades of brown or black in a single growth. A mole typically has one uniform color.
• Diameter: Melanoma’s size can be greater than 6 mm and it is able to continue to grow further. However, it can sometimes be smaller than this.
• Evolving: Melanoma can change dramatically in color, size, and shape in addition to the appearance of a new symptom such as bleeding, itching or crusting.

An excisional biopsy might be recommended by the healthcare provider once melanoma is suspected. In order to obtain the biopsy, a local anesthetic is injected and minor operation is conducted to remove the entire abnormal area of skin; then, the tissue will be analyzed carefully under the microscope to:

• Help confirm the diagnosis by observing abnormal melanoma cells.

Examine the thickness of melanoma by observing how deep it has spread into the skin.CT scans or other types of X-rays may be suggested to see if the tumor has spread to other regions once melanoma is positively diagnosed.

The size and stage of cancer and the overall health and personal preferences of the patient will determine the best treatment option for each case. Treatment option may include:

• Surgery: Removing the melanoma through surgery may be the only treatment needed for people with early-stage melanomas.

• Lymphadenectomy: A surgical procedure to remove lymph nodes to where cancer has spread.

• Immunotherapy: Treatment that supports the immune system of the patient to fight the cancer by using its own defense mechanisms.
• Targeted therapy: The use of drugs that temporarily shrink the cancer. Some patients appear to be fully cured when using this method of treatment. Vemurafenib, trametinib, and dabrafenib are commonly used targeted therapy drugs to treat advanced melanoma.

• Chemotherapy: This treatment is able to eliminate cancer cells, but also affects some normal cells, which is why it causes multiple side effects.
• Radiation therapy: This type of cancer therapy is done by using certain X-rays that are able to eliminate cancer cells, but also affects some normal cells.

Other treatment options that may be recommended in case of melanoma include:

• Clinical trials: It is the clinical attempts to uncover new possible medications or other treatment. A healthcare provider might advise a clinical trial when the treatment being studied have the potential to treat a patient.
• Vaccines for melanoma: Vaccine treatment is still unavailable in large scale because it is still under testing. Usually, it is only given as part of a clinical trial.
• Adoptive T-cell therapy: Another kind of treatment that encourages the immune system of the patient to fight the cancer.
• Palliative care: This kind of care revolves around improving quality of life of the patient and relieving associated symptoms.

Melanoma has the potential to reach other body parts very quickly. Various side effects, including pain, nausea, fatigue, hair loss, appetite loss are associated with melanoma treatment, especially chemotherapy and radiation therapy.

It is still unclear how to prevent melanoma completely because of many involved risk factors, such as family history, are uncontrollable. However, a variety of measures that help lower the risk include:

• Awareness of abnormal moles.
• Avoiding the weakening of the immune system.
• Restricting exposure to UV rays by:

• Seeking shade from the sun.
• Using sunscreen with a sun protection factor of 15 or more.
• Avoiding the use of tanning beds and sunlamps.
• Wearing covering clothes and a wide-brimmed hat when out in the sun.

It is especially important to protect children from the sun because they usually spend more time outdoors and can burn more easily.

The outlook for a patient with melanoma has been showing improvement over that past 25 years. The majority of people who had surgically removed a melanoma will have no further problems. Amongst all types of cancer, patients with melanoma currently have one of the most positive outlook.

It is still unknown why survival rate is slightly better for women than it is for men, but it may be because it is possible for women to report their case to a doctor at an earlier stage.

Age can play a role in the prognosis of melanomas; younger people have a better prognosis than older ones.

According to a study published in the Expert Review of Anticancer Therapy, the annual increase in the incidence rate of melanoma for Caucasians worldwide has been approximately 3–7% per year. The highest incidence rate of melanoma in the globe is in Australia. Melanoma remains extremely rare among black populations and most cases tend to be of the acral lentiginous subtype.

A study published in the UK journal Annals of Oncology shows that the incidence of malignant melanoma in Europe varies from 3 to 5 per 100,000 per year in Mediterranean countries and from 12 to 25 (and rising) in Nordic countries.

According to the American Cancer Society, the average age of people when melanoma is diagnosed is 63. The risk of melanoma increases as people advance in age. However, melanoma is common even among young people who are less than 30 years old. Melanoma is one of the most common cancers in young adults, particularly young women.