Nevuses – are lesions of the skin and mucous membranes resulting from the abnormal development of melanocytes. There are many types of nevi that differ in clinical and dermatoscopic characteristics.
In most cases, the nature of such pigmented lesions is benign. These forms of moles are harmless and remain unchanged throughout the patient’s life, unless the conditions are suddenly created that can induce carcinogenic phenomena and favor the transformation of benign to malignant forms.
Causes of nevi
The reasons why the above proliferative process occurs are not yet fully disclosed and studied. However, there are a number of factors that have a definite effect, these are:
- genetic predisposition;
- immune status;
- exposure to ultraviolet radiation;
- certain pharmacological preparations;
- Phototype 1 (fair skin and eyes).
Some of the nevi can become more visible during puberty and pregnancy, showing a certain degree of sensitivity to hormones.
Symptoms of malignant nevus
Malignant nevi have various clinical characteristics. Their degree of pigmentation, as well as sizes and shapes may vary. As a rule, these lesions look like papules or nodules, partially elevated or flat. They occur, as a rule, on the skin, but are also able to affect the mucous membranes of the mouth, genitals, conjunctiva and sclera.
Чтобы как можно раньше распознать угрозу злокачественного перерождения, чрезвычайно важно обращать внимание на изменения формы, цвета, внешнего вида и количества родинок.
In order to recognize the threat of malignant transformation as early as possible, it is extremely important to pay attention to changes in the shape, color, appearance and number of moles.
At risk are moles with an irregular and asymmetric shape with serrated edges. An increase in the diameter of the nevus (more than 6 mm) and its thickness can serve as evidence of malignant evolution, especially if such changes occur in a short period of time. The color of the nevus does not bode well, if it is not homogeneous within the same formation and becomes very dark or has reddish-brown, white, or blue shades.
Malignant nevi change their consistency, they soften or harden, become hardened or tend to“crumble”, surrounded by a reddish pattern.
Other warning signs of malignant nevus are: inflammation of the surrounding skin, itching, pain, bleeding, effusion, desquamation, ulceration.
Possible consequences of nevi
The most serious evolution of malignant nevus is skin cancer, including melanoma. This neoplastic disease is extremely aggressive, as it manages to spread both in depth and in length, reaching the lymph nodes and organs far from the place of origin, which leads to the occurrence of metastases very quickly.
You should be aware that nevi do not necessarily lead to melanoma or other malignant skin epitheliomas, but they should be kept under the constant supervision of a dermatologist. After dermatoscopy, the doctor will determine whether it is advisable to perform surgical removal of the lesion with histological examination of the tissue, or whether it is better to plan a new follow-up visit in a few months.
Dermatoscopy in the «Bogoliuby MC » is carried out with a digital dermatoscope DERMASKOPE polarizer HR 200, made in the Netherlands, and the removal of nevi is carried out by radio wave coagulation using the «Surgitron »apparatus.
