Lipoma

What is a Lipoma

Lipoma represents not only the most common form of benign tumor of adipose tissue, but also the most common non-cancerous neoplastic condition among all soft tissues.

Lipoma is caused by abnormal and excessive development of lipid cells (fat cells), which are surrounded by fibrous capsules.

Incidence

Lipomas can develop in any area of ​​the body and occur in both sexes, but more frequently in men than in women.
Furthermore, the formation of these benign tumors appears to be more frequent in patients over the age of fifty.
Statistics reveal that 1% of the population is affected by various forms of lipoma: in children, cancers of the lipid tissue usually occur in conjunction with Bannayan-Zonana disease (genetic pathology characterized by the development of multiple hemangiomas and lipomas, associated with macroencephaly).

Features

Lipomas represent palpable subcutaneous reliefs. They appear as accumulations of fat, usually surrounded by a kind of fibrous tissue capsule. They are usually soft, move with finger pressure and are not painful to the touch. If they are not removed, they can remain in situ for many years.
Usually, these benign formations occur most frequently in the shoulders, neck, arms, abdomen, back and thighs and involve the subcutaneous fatty tissue. However, in some cases, lipomas can occur even deeper in internal organs such as the kidneys or intestines.
Typically, lipomas expand up to 15 centimeters, but in some people these growths can evolve into grotesque shapes (giant lipoma) and weigh even 5 kilos.

Classification

The types of lipomas currently known are many and can be classified according to different factors.

For example, they can be divided according to the appearance of the cells that compose them and according to the type of tissues involved. In fact, there are variants of lipoma which - in addition to being made up of fat - are also made up of other types of tissues. In this regard, we can remember:

• The conventional lipoma (consisting of the so-called "white fat").
• Hibernoma (otherwise known as glandular lipoma), which is a rare benign tumor that develops in the neck, armpits and mediastinum and affects brown fatty tissue.
• Angiolipoma, consisting of fatty tissue and blood vessels.
• Angiolipoleiomyoma, which is a circumscribed subcutaneous tumor, characterized by smooth muscle cells, blood vessels, lipid and connective tissue.
• Myelolipoma, which is a type of lipoma consisting of adipose tissue and hematopoietic tissue.
• The racemous lipoma which - unlike all the others - is not surrounded by any capsule.

Another classification of lipomas can be made on the basis of the area of ​​the body in which they occur. In this case, we can distinguish:

• Superficial subcutaneous lipoma: the most common form of lipoma, which occurs just below the surface of the epidermis. It can develop in any area of ​​the body that has fat, but there is a greater incidence in the trunk, thighs and arms.
• Palmar lipomas: lipoma that affects the hand.
• Intestinal lipoma: is a benign form of lipoma located in the intestine. It can lead to bleeding.
• Cardiac lipoma: Located near the heart, the lipoma, although benign, could be dangerous. If it increases in size, in fact, there is a risk that the lipoma occludes the heart valves.
• Sacral lipomas: lipoma that affects the sacral region.
• Meningeal lipomas: lipoma that occurs at the level of the meningeal sheaths that could cause neuronal damage.
• Intramural lipomas: Lipoma that affects the colon.

Again, lipomas can be classified into:

• Solitary lipomas: circumscribed lipomas, which could however be multiple.
• Multiple lipomas: Benign lipomas that are not sharply circumscribed like solitary lipomas.

Causes

The etiopathological picture underlying the formation of the lipoma has not yet been fully clarified.
However, some researchers believe that genetic predisposition is one of the main factors involved.
Other scholars believe more reliable the theory according to which a trauma of a relatively large entity would represent the main cause of the lipoma; in the event that the neoplasm is already in progress, a traumatic event could potentiate its progression (post-traumatic lipoma).
Another theory, on the other hand, relates the lipoma to the alteration of the obesity genes, but even in this case there is a lack of scientific evidence.

Symptoms

For further information: Lipoma Symptoms

Apart from the formation of a subcutaneous relief with a soft and mobile texture to the touch, lipomas - as a rule - do not cause other symptoms. Often and willingly, they are not even visible and remain unchanged and asymptomatic for the duration of the patient's life.

Still others, however, may grow causing concern because - depending on the area in which they occur and depending on the "extent of" volume increase - they could become dangerous putting the patient's health at serious risk (just think, for example, of lipomas meningeal or cardiac).
Finally, lipomas may cause pain if, as they grow, they compress nerve endings. In the worst - and fortunately rarer - of cases, however, pain could be the sign of conversion into a malignant form of cancer.

Complications

As mentioned, although it is a rare event, it is not impossible that a lipoma can evolve and become complicated, leading to the formation of a malignant tumor.
When this occurs it is referred to as liposarcoma. It is a type of cancer that occurs anywhere in the body. It can metastasize giving rise to all the consequences of the case.

When to be alarmed?

Since the transformation into a malignant tumor cannot be completely excluded, it is always good to keep the lipoma under control, in order to identify any changes or alterations of its characteristics that could represent a bell from the weapon.
In detail, it is necessary to consult the doctor if the lipoma:

• It becomes a hard and / or painful mass;
• It increases in volume very quickly;
• It also grows back after surgical removal;
• It undergoes alterations of any kind.

Diagnosis

The diagnosis of lipoma can be made by the doctor with a simple visual examination. It will then have to evaluate all the symptoms presented by the patient, in order to exclude any other pathologies.
In some cases - to confirm the diagnosis, thus ascertaining the true nature of the subcutaneous relief - it may be useful to perform a biopsy of the lipoma, or perform instrumental analyzes such as CT or magnetic resonance imaging.
As for the lipomas that develop in correspondence of internal organs (such as, for example, those that are formed in the gastrointestinal tract), instead, in order to perform a correct diagnosis, it is useful to resort to an "endoscopy.

Treatment

It is not always essential to adopt resolving methods for lipoma. In fact, as repeatedly reiterated in the course of the article, in most cases the lipoma is asymptomatic and remains a benign form. In fact, it is true that it sometimes regresses spontaneously.
However, the removal of the tumor is recommended when the lipomas become a real aesthetic problem, which compromises the image of the person: in fact, the lipomas can increase in size, become painful or annoying, become inflamed or hinder movement. circumstances, the surgeon may encourage the patient to undergo certain interventions, such as:

• Surgical excision.
• Liposuction.
• Laser treatment.
• Innovative technique that induces lipolysis: a substance is injected into the lipoma (usually steroids or phosphatidylcholine) which favors tumor lipolysis.

To conclude, the lipoma represents one of the least dangerous neoplastic forms and the subject may not even notice its presence. However, the lipoma may remain in the same area where it originated, cause no symptoms and regress spontaneously.

Summary

To fix the concepts ...

Illness Lipoma: most common form of benign tumor of adipose tissue Features It can expand up to 15 cm in diameter and can reach a weight of 5 kg (rare form). Generally lipomas represent subcutaneous reliefs that are palpable, soft and painless to the touch. They appear as accumulations of fat and, if not removed, can remain in situ for many years. Incidence It affects 1% of the population and in most cases does not create problems. Areas of interest They can develop in any area of ​​the body characterized by adipose tissue. Eziopathological picture Doubtful origin. Etiological hypotheses:

• Genetic predisposition
• Consequence of trauma
• Possible connection with obesity genes

Symptoms Formation of one or more subcutaneous reliefs, generally asymptomatic.
Pain can be felt if the lipoma compresses the nerve endings, or if it transforms into liposarcoma. Classification Lipomas can be classified according to the appearance of the cells and the type of tissues that constitute them:

• Conventional lipoma
• Hibernation (affects brown adipose tissue)
• Angiolipoma
• Angiolipoleiomyoma (circumscribed tumor consisting of smooth muscle cells, connective tissue, fat and blood vessels)
• Myelolipoma
• Racemous lipoma

Alternatively, lipomas can be classified according to the area in which they occur:

• Superficial subcutaneous lipoma (most common form)
• Palmar lipomas
• Intestinal lipoma
• Heart lipoma (can obstruct heart valves)
• Liposarcoma (malignant lipoma)
• sacral lipomas
• Meningeal lipomas
• Intramural (colon) lipomas

Or, they can be classified into:

• Solitary lipomas (circumscribed)
• Multiple lipomas

Diagnosis Physical examination, instrumental examinations (CT, magnetic resonance) and biopsy.
For lipomas that develop in internal organs, an adequate endoscopy is useful. Remedies

• Surgical excision
• Liposuction
• Laser treatment
• Innovative technique that induces lipolysis: a substance (usually steroids or phosphatidylcholine) is injected into the lipoma which promotes lipolysis of the lipoma