Introduction
Lipomas are benign tumors consisting of fat cells, which are mostly located in the subcutaneous fatty tissue, more rarely also in internal organs or within muscles. They are among the more frequent benign tumors, although the exact cause has not yet been clarified. About 16 percent of people can detect a lipoma, and both sexes are equally affected. However, the incidence is higher between the fourth and fifth decade of life, as well as in certain hereditary diseases such as lipomatosis dolorosa or neurofibromatosis. Preferably lipomas occur on the trunk and in the head and neck area, less frequently they are found on the extremities.
Symptoms
Lipomas are tumors that are rich in fat cells and blood vessels. They usually have a soft consistency and are easily palpable in the subcutaneous fatty tissue. However, if they have a high proportion of connective tissue (e.g. in fibrolipomas), they can also impress as a somewhat harder node under the skin.
As lipomas in most cases do not cause any complaints, they are often only discovered by chance as a palpable finding. As a rule, they grow very slowly and can therefore only be noticed for the first time years later. Their size is very variable, so that diameters between 1 and 10 cm and more can be present.
Smaller lipomas in the subcutaneous fatty tissue are therefore often only noticeable as small, shifting, soft, compressible nodes under the skin, which can only be felt by targeted palpation, as otherwise they do not cause any symptoms. Larger lipomas, on the other hand, are visible to the naked eye as a distinct bulge under the skin. Complaints and symptoms generally only occur with lipomas when they compress surrounding structures such as nerves or vessels and organs due to their position or size.
For example, if they are located in the subcutaneous fatty tissue directly in the area of joints, they can be compressed during movements, which can lead to restricted movement or an unpleasant feeling of pressure or even pain. In general, lipomas that are in close proximity to nerves and which push them off due to growth in size or during movement can become noticeable for the first time through pain. However, a close location in the vicinity of larger vessels can also lead to symptoms, for example if a slightly larger lipoma on the neck leads to a compression of the carotid artery or to movement restrictions in the neck muscles.
Deeper located lipomas near, in or on internal organs are rare (1-2%), but they can lead to various symptoms, which are caused by organ dysfunction within the scope of their space requirement. Much more frequent and harmless are lipomas of the trunk of the body, which occur preferably on the back, the abdomen, the chest, the shoulder or the upper arm and thigh, as they only rarely lead to serious complaints, but rather represent a cosmetic problem. On the back, lipomas above a certain size can on the one hand create a diffuse feeling of pressure (especially when lying down), but on the other hand, they can also lead to nerve pain, numbness or sensory disturbances in the surrounding skin area or to pressure-related pain in the back muscles or tendons when the surrounding area is compressed.
