Mastocytosis (synonym: mastopathy) is a skin disease manifested by the formation of spontaneous rashes that have typical signs of a proliferative process in the skin. Mastocytoses can be both benign and malignant (a benign disease has a longer lifespan and is more likely to survive with such a diagnosis, while a malignant disease more often leads to death). Any new or changed moles or formations are subject to mandatory examination by a doctor. Mast cells (mast cells) perform one of the important functions in the body - they regulate the immune system. If the body does not give visible allergic reactions to the interaction of the immune system with parasites and other external factors, then this is entirely due to these cells. The average human body contains up to seventy thousand of these mast cells in various parts of the body. They are activated by allergens and other substances, releasing histamine and other beneficial components for the body. As mentioned above, negative features of the functioning of mast cells include their accumulation in the intercellular space of the connective tissue of the dermis (skin, joints, mucous membranes and connective tissues). Mast cells are concentrated in the layers of the epidermis, blood vessels (especially in the microvasculature), myocardium, liver, lungs, spleen, bone marrow, etc.