Melanoma is a malignant tumor that develops from melanocytes, cells of the epidermis which produce melanin, the pigment that colors human skin, hair, and eyes. These cells are located near the network of blood vessels that supply the dermis; they can easily go into the bloodstream and spread anywhere in the body to lead to the formation of metastases. This is why melanoma skin cancer tends to be aggressive. Early therapies are essential to avoid fetal complication. For more info, please see melanoma treatment.

Melanoma is account for a minority of skin cancers, but it is increasing in Western countries (United States, Canada, United Kingdom…) where sun exposure is more common. The highest rates are observed in the countries closest to the equator, except in Europe where the highest rates are found in the Nordic countries. In Western countries, melanoma incidence has doubled every decade for at least 30 years. Currently, it affects 7 out of 100,000 of individuals worldwide, corresponding to 10% of skin cancers and 1% of all cancers.

But this incidence varies considerably depending on the geographic area and race. For instance, in certain countries of Northern Europe the incidence is less than 5 per 100,000, while in Queensland, Australia the rates are 56 new cases per year for men and 43 for women per 100,000 individuals. African is rarely affected by it comparably to white people. For information on USA and incidence and other races, please see melanoma skin cancer statistics.

Types of Melanoma

There are four main types of melanoma skin cancer: superficial spreading melanoma; lentigo maligna melanoma; nodular melanoma; and acral lentiginous melanoma, which is the rarest form. Superficial spreading, nodular and lentigno maligna melanomas account for up to 90% of melanoma cases.

Melanoma signs can be detected early. The tumor develops first at the skin surface before continuing deeper. In some cases, the starting point is a mole (nevus) that turns into cancerous if no treatment is used to stop it. But it is estimated that about 80% of cases, the tumor is manifested by the appearance of a pigmented patch on healthy skin that looks like a mole. That is, any abnormal skin development should not be neglected. See melanoma signs and symptoms

Although the rarest of skin cancers, melanoma is also the more serious the fact it tends to rapidly spread from the initial site and invade other organs to form metastases. However, when detected and treated very early in its development stage, the tumor can be cured. See melanoma treatment for more info.

Are All Moles Cause Skin Cancer?

Moles in large numbers, large and irregular sizes, predispose to the occurrence of melanoma skin cancer. However, the risk of progression to cancer is about 25% or less and the vast majority of melanomas occur outside of a mole. It is therefore not recommended to anyone to remove moles which have normal aspect as prevention or precaution. Only medical professionals can perform diagnostic procedures to determine if a mole is precancerous or cancerous.

After the growth is confirmed to be malignant, the choice of the melanoma treatment is personalized and tailored depending on each situation. Usually, several physicians from different specialties meet in multidisciplinary team meetings (MDT’s) to discuss the best treatment options which will bring a better solution in the fight against the cancer.


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  4.  types and statistics of melanoma skin cancer   
  5. World Cancer Report 2014. World Health Organization. 2014. pp. Chapter 5.14. ISBN 9283204298.
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