Introduction
A mole, known in medicine as a nevus, is a benign proliferation of pigment-forming cells called melanocytes. Liver spots are common and can be found in almost all people. The majority of liver spots are acquired, i.e. they only develop in the course of life.
Liver spots that have existed since birth, i.e. are congenital, are rarer. Congenital liver spots can also be called birthmarks. Moles can change in shape and color in the course of time but can also regress completely.
The majority of liver spots are harmless new formations which do not require any therapy. However, certain forms of liver spots carry the risk of malignant degeneration. This means that some moles can develop into a malignant cancer, the so-called malignant melanoma (black skin cancer).
In order to be able to recognize and treat the process of malignant degeneration at an early stage, it is important to have liver spots checked by a dermatologist (dermatologist) at regular intervals, for example if a liver spot itches. In particular, liver spots that change in color (e.g. a black discoloration) and shape (e.g. a growing or an unevenly growing mole) should be checked regularly. In addition, itching, weeping, aching, stinging, burning and bleeding moles can indicate the development of a malignant melanoma. Moles that show signs of malignant degeneration are surgically removed by a dermatologist at an early stage.
Cause
Liver spots are caused by an increase in pigment-producing cells, the melanocytes. Why these cells multiply has not yet been conclusively clarified. It is suspected that genetically modified precursor cells of the pigment-producing melanocytes migrate into the skin, multiply there, then accumulate in the form of nests and thus form a liver spot.
Melanocytes are able to produce a brown dye, melanin, which makes the mole look brown or black. On the other hand, there are clearly identified influencing factors that can promote the appearance of liver spots. These influencing factors play a major role, especially in the case of acquired liver spots, i.e. those that develop in the course of life.
They include UV radiation (for example, when sunbathing in summer), hormonal changes (for example, during puberty or in the form of skin changes during pregnancy), family history or a weakened immune system (for example, in the presence of an infection). Especially the influencing factor UV radiation can also cause pathological changes in already existing liver spots. A distinction is made between acquired liver spots and congenital liver spots that are already present at birth.
In this case, a familial disposition is suspected above all. Furthermore, there are various clinical pictures (for example neurofibromatosis), in which, in addition to other symptoms, the mutation of the melanocytes can lead to the appearance of numerous liver spots. Changes in already existing liver spots can have different causes.
Often, changes in liver spots are not caused by pathological processes. For example, very dry skin can cause severe itching of the skin, which also affects the liver spots, so that the liver spot also itches. Severe scratching of itchy skin and itchy liver spots can lead to bleeding and the liver spot can also bleed. Nevertheless, changes in liver spots, such as a change in shape, size or color, as well as the sudden appearance of itching, weeping, pain, stinging and burning, and bleeding in liver spots should always be taken seriously, as in the worst case they can indicate the development of a malignant cancer, malignant melanoma. Malignant melanoma requires immediate treatment.
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