Melanoma is a cancer of melanocytes present in the skin that produces the pigment melanin. Most melanomas appear on the skin, but it may also develop in almost any organ of the body, including the eye, brain, and lymph nodes. It is a type of skin cancer that can spread to other organs in the body. It rarely appears in internal organs, such as intestines. It is more serious forms of skin cancer because it tends to spread to other organs of the body that may lead to serious illness and even death.
The stages of Melanoma depend on the thickness, ulceration, lymph node involvement, and the presence of distant metastasis.
Stages 1 and 2 – the cancerous growth is limited to the skin only.
Stage 3- the skin cancer is spread to the local areas through the lymphatic drainage.
Stage 4- the cancerous cells have traveled to distant areas to other organs, usually through the bloodstream.
The typical sign of melanoma is the presence of a new mole or a change in an existing mole that can appear anywhere on the body. Its commonest site is back in males and the legs in females. It rarely appears in sun-protected areas such as the buttocks and the scalp. In most cases, its characteristic features can be understood by following ABCDE criteria-
A stands for asymmetrical shape- moles are irregular in shapes, such as two very different-looking halves.
B stands for irregular border-moles have irregular, notched, or scalloped border.
C stands for changes in color- they have many colors with an uneven distribution of color.
D stands for diameter- the mole has a diameter of more than 1/4 inch (about 6 millimeters).
E stands for evolving- the moles may exhibit new signs and symptoms, like new itchiness or bleeding.
DNA damage in the skin cells causes out of control growth of these cells. It can eventually grow to form a mass of cancerous cells.
Other causes of melanomas are-
Combination of environmental and genetic factors
Exposure to ultraviolet (UV) radiation from the sun
From tanning lamps and beds
Factors that may increase the risk of melanoma are
Caucasian (white) race
Fair skin, light complexion, light hair, and light-colored eyes
A history of sun exposure, especially in childhood
A large number of moles (more than 100)
Large, irregular shaped or "funny looking" moles
History of melanoma in Close blood relatives
Weak immune system
In most cases, melanoma is diagnosed with the help of the biopsy. In this procedure, the suspicious mole is removed and is studied in the laboratory to examine its cancerous nature under a microscope.
Another test is recommended when there is doubt that melanoma is spread to the lymph nodes. It is called a sentinel node biopsy.
The primary treatment for melanoma is the surgical excision of the mole. But it depends depend on age, shape & size, the stage during diagnosis and extent of its spread. If it is detected in the early stage, it is treated successfully with surgery. If it has spread to lymph nodes, then surgical removal of nearby lymph nodes is recommended.
If melanoma is diagnosed after it has progressed to an advanced stage, then treatment is focused on slowing down the spread of cancer and reduce symptoms. More in-depth and more advanced cancers may require more extensive surgery to get treated.
The treatment focuses on the reduction of symptoms, usually involves medicines that target specific genetic alterations in melanoma, like BRAF inhibitors, etc. Medicines are selected that can boost the immune responses of the body to the cancerous growths (so-called checkpoint therapies). Some treatments using immunotherapy or chemotherapy are often selected.