Melanoma is a type of cancer that develops in the melanocytes, which are the pigment cells present in the skin. Melanoma is more serious/aggressive type of cancer. It can also occur in the eyes and in rare instances, within internal organs. Melanomas are most likely to occur on the chest and back in men and on the legs in women. Neck and face are the other common sites of occurrence for this type of cancer. Melanomas often resemble moles; some develop from moles. The majority of melanomas are black or brown, but they can also be skin-coloured, pink, red, purple, blue or white.
The exact cause of all melanomas isn't clear, but exposure to ultraviolet (UV) rays from sunlight or tanning lamps and beds increases the risk of developing melanoma. Limiting the exposure to UV rays can help reduce your risk of melanoma.
The risk of melanoma seems to be increasing in people under 40, especially women. Knowing the warning signs of skin cancer can help ensure that cancerous changes are detected and treated before the cancer has spread. Melanoma can be treated successfully if it is detected early.
Melanomas can develop anywhere on the body. They most often develop in areas that have had exposure to the sun, such as your back, legs, arms and face. Melanomas can also occur in areas that don't receive much sun exposure, such as the soles of your feet, palms of your hands and fingernail beds. These hidden melanomas are more common in people with darker skin. Sudden occurrence of moles, sores, lumps or marks on the skin may be a key sign of melanoma or other types of skin cancer.
common or early signs of melanoma are:
- A change in an existing mole
- Development of new pigmented skin
- Unusual looking growth on the skin
- Pigments that spread from the border of a spot into the surrounding skin
Melanoma doesn't always begin as a mole. It can also occur on otherwise normal-appearing skin. Normal moles have a uniform colour — be it tan, brown or black — with a distinct border separating the mole from the surrounding skin. They're usually shaped oval or round and are smaller than 1/4 inch. Most people have around 10-45 moles many of which develop much later in life, around the age of 50. Many moles may change appearance over time and few may even disappear as a person ages. Unusual moles may indicate melanoma. Below are the ABCDEs of Melanoma:
- A – Asymmetry: In an asymmetrical mole, if a line is drawn through the middle, the two halves will not match. These are a warning sign for melanoma.
- B – Border: A benign mole has smooth, even borders, unlike melanomas. The borders of an early melanoma tend to be uneven. The edges may be scalloped or notched.
- C – Colour: Most benign moles are all one colour — often a single shade of brown. Having a variety of colours is another warning signal. A number of different shades of brown, tan or black could appear. A melanoma may also become red, white or blue.
- D – Diameter: Benign moles usually have a smaller diameter than malignant ones.
- E – Evolving: Common, benign moles look the same over time. Be on the alert when a mole starts to evolve or change in any way. When a mole is evolving, see a doctor. Any change — in size, shape, colour, elevation, or another trait, or any new symptom such as bleeding, itching or crusting — points to danger.
Melanomas can also develop in areas of the body that have little or no exposure to the sun, such as between the toes and on the palms, soles, scalp or genitals. These are sometimes referred to as hidden melanomas because they occur in places most people wouldn't think to check. Hidden melanomas include:
- Melanoma under a nail. Acral-lentiginous melanoma is a rare form of melanoma that can occur under a fingernail or toenail. It can also be found on the palms of the hands or the soles of the feet.
- Melanoma in the mouth, digestive tract, urinary tract or vagina. Mucosal melanoma develops in the mucous membrane that lines the nose, mouth, oesophagus, anus, urinary tract and vagina. Mucosal melanomas are especially difficult to detect because they can easily be mistaken for other far more common conditions.
- Melanoma in the eye. Eye melanoma, also called ocular melanoma, most often occurs in the uvea — the layer beneath the white of the eye (sclera). An eye melanoma may cause vision changes and may be diagnosed during an eye exam.
The skin cells develop in a controlled manner where the healthy newer cells push older cells toward your skin's surface. The older cells on the surface die and eventually fall off. However, when some cells develop DNA damage, new cells may begin to grow out of control and can eventually form a mass of cancerous cells. What damages the DNA in skin cells and how this leads to melanoma isn't clear. It's most likely a combination of factors which includes environmental and genetic factors. Doctors believe exposure to ultraviolet (UV) radiation from the sun and from tanning lamps and beds is the leading cause of melanoma. While UV radiation could be the case, it doesn't cause all melanomas, especially hidden melanomas. This indicates that other factors may contribute to your risk of melanoma.
Some of the risk factors are:
- Fair skin: Having less melanin in the skin means there is lesser protection from damaging UV radiation. This increases the chances of getting melanoma
- A history of sunburn: One or more severe, blistering sunburns can increase your risk of melanoma.
- Excessive UV exposure: Exposure to UV radiation, which comes from the sun and from tanning lights and beds, can increase the risk of skin cancer, including melanoma.
- Living closer to the equator or at a higher elevation: People living closer to the earth's equator, where the sun's rays are more direct, experience higher amounts of UV radiation than do those living in higher latitudes. In addition, if you live at a high elevation, you're exposed to more UV radiation.
- Having many moles or unusual moles: Having more than 50 ordinary moles on your body indicates an increased risk of melanoma. Also, having an unusual type of mole increases the risk of melanoma. Known medically as dysplastic nevi, these tend to be larger than normal moles and have irregular borders and a mixture of colours.
- Family history of melanoma
- Weak immune system
Sometimes melanoma can be detected simply by looking/examining the skin however, the only way to accurately diagnose melanoma is through a biopsy. In this procedure, all or part of the suspicious mole or growth is removed and a pathologist analyses the sample. The biopsy procedures to diagnose melanoma are:
- Punch Biopsy: During a punch biopsy, your doctor uses a tool with a circular blade. The blade is pressed into the skin around a suspicious mole, and a round piece of skin is removed.
- Excisional Biopsy: In this procedure, the entire mole or growth is removed along with a small border of normal-appearing skin.
- Incisional Biopsy: With an incisional biopsy, only the most irregular part of a mole or growth is taken for laboratory analysis.
Usually doctors prefer punch or excisional biopsy however, in cases where the suspected mole/growth is too large, an incisional biopsy may be done.
Treatment plans are suggested based on the stage of cancer and other factors and the options include:
- Surgery: The surgeon may remove the mole/growth and some surrounding healthy tissue. If the melanoma has spread to nearby lymph nodes, the surgeon may remove the affected nodes. Additional treatments before or after surgery also may be recommended.
- Chemotherapy: Chemotherapy uses drugs to destroy cancer cells. Chemotherapy can be given intravenously, in pill form or both so that it travels throughout your body. Chemotherapy can also be given in a vein in your arm or leg in a procedure called isolated limb perfusion. During this procedure, blood in the arm or leg isn't allowed to travel to other areas of your body for a short time so that the chemotherapy drugs travel directly to the area around the melanoma and don't affect other parts of your body.
- Radiation therapy: This treatment uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy may be recommended after surgery to remove the lymph nodes. It's sometimes used to help relieve symptoms of melanoma that has spread to another area of the body.
- Immunotherapy: It aims to boosts the immune system to help the body fight cancer. These treatments are designed of substances produced by the body or similar substances produced in a laboratory. Side effects of these treatments are similar to those of the flu, including chills, fatigue, fever, headache and muscle aches.
- Targeted therapy: Targeted therapy uses medications designed to target specific vulnerabilities in cancer cells. Side effects of targeted therapies vary, but tend to include skin problems, fever, chills and dehydration.