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
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
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
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.
Stern RS. Prevalence of a history of
skin cancer in 2007: results of an incidence-based model. Arch Dermatol. 2010
Rogers, HW, Weinstock, MA, Harris,
AR, et al. Incidence estimate of nonmelanoma skin cancer in the United States, 2006. Arch Dermatol
Cancer Report 2014.
World Health Organization. 2014. pp. Chapter 5.14. ISBN 9283204298.
Melanoma of the Skin, Cancer Fact
Sheets, National Cancer Institute, SEER database, 2007. http://seer.cancer.gov
SC; Lange, JR (October 2014). "Epidemiology, risk factors, prevention, and early detection of
melanoma.". The Surgical clinics of North America
94 (5): 945–62, vii. PMID 25245960.