Lentigo Malignant Basics

Acronyms Medical

Lentigo maligna is a diffuse, flat, brown-black discoloration of the skin caused by atypical melanocytes. This phenomenon is caused by exposure to the sun and corresponds to a preliminary stage of malignant melanoma. The affected skin area is surgically completely removed.

What is lentigo maligna?

Signs of lentigo maligna should always be checked by a dermatologist . Since the skin changes are a precursor to skin cancer, an early diagnosis can save the patient’s life.┬áSee AbbreviationFinder for abbreviations related to Lentigo Malignant.

In lentigo maligna, accumulations of atypical melanocytes form in the epidermis. The melanocytes are the cells in the skin that produce the pigment and deliver it to the surrounding skin cells. Lentigo maligna is a process of degeneration of the pigment-producing cells that takes place in the epidermis of the skin. Degenerate melanocytes are also known as melanomas.

Since the melanocytes in lentigo malignant have not yet become actual cancer cells, but only appear atypical, the disease can also be referred to as melanoma in situ. The peak of this disease is around 50 years of age. Slightly more women suffer from the phenomenon. Many sources assume that the risk of degeneration of atypical cells is more than 50 percent. Some even suspect that atypical melanocytes almost always develop into a malignant melanoma. However, this development can take several decades.


As a precursor to melanoma, lentigo maligna is an in situ stage of black skin cancer. So far, this disease has mainly been associated with UV radiation. Since the disease has increased in some families, however, science assumes a genetic disposition as the basis. In this case, the genetic disposition relates primarily to the color of the skin. Thus, well-pigmented people are much less likely to be affected by melanoma than people with genetically light skin.

This is due to the filtering effect of the brown-black melanin. This dark type of melanin is one of two different types of pigment found in human skin. The skin color of every human being results from the genetically determined combination of light and dark pigment components. In pigmented people, there is more of the dark dye present. Studies have shown that this substance renders solar energy harmless to a high percentage.

Symptoms, Ailments & Signs

Lentigo maligna occurs primarily on skin in the armpits, face, neck and forearms or lower legs. As a rule, the affected skin area is damaged by radiation, i.e. it was already involved in sunburn. Brown to black pigmented and inhomogeneous discolorations of the epidermis become visible on these skin areas.

As a rule, these spots are only diffusely limited and not raised, but flat. In rare cases, lentigo maligna can also affect the eye. In this context, the phenomenon also occurs in pigmented people, since the skin in their eyes is not pigmented. The discolouration is probably related to damage in the DNA of the melanocytes caused by exposure to the sun. In this way, a malignant cell clone of the melanocytes can form in the epidermis. Normally, lentigo maligna does not cause pain, itching or other symptoms.

Diagnosis & course of disease

The first suspicion of lentigo maligna arises in the context of anamnesis and visual diagnostics. The suspicion is confirmed histopathologically. In the differential diagnosis, the doctor must primarily consider age spots, but also an already mature melanoma that is spreading superficially. The prognosis for lentigo maligna promises a nearly 100 percent chance of recovery. Even if a lentigo maligna melanoma has already developed, the chances of recovery are still good.


Lentigo maligna usually requires treatment. Without this, the complaint can develop into skin cancer, which in the worst case can be fatal for the patient. As a rule, with this disease there are various brown regions on the skin. These regions must therefore be completely removed by surgery.

In many cases, those affected are ashamed of the symptoms and feel uncomfortable with the spots or suffer from reduced self-esteem. Furthermore, this disease can also occur in the eye of the patient and lead to various visual problems and limitations in everyday life. It is not uncommon for those affected to suffer from pain on the skin or itching due to lentigo maligna.

These usually only get worse if the person concerned scratches the area in question. This can also lead to bleeding and scars on the skin. There are usually no complications during the treatment itself. The affected areas are removed, after which the patient is still dependent on radiation. Furthermore, there is usually no reduction in the life expectancy of the patient.

When should you go to the doctor?

Signs of lentigo maligna should always be checked by a dermatologist . Since the skin changes are a precursor to skin cancer, an early diagnosis can save the patient’s life. Warning signs such as black discoloration on damaged areas of skin therefore always require a comprehensive medical examination. If the skin suddenly changes, this must also be clarified quickly. Any bleeding or scarring should also be reported to a doctor. Lentigo maligno occurs mainly in people with light skin.

Those who belong to this risk group must ensure adequate sun protection. Should a sunburn nevertheless occur, the affected skin area must be monitored by a doctor. If the skin changes mentioned occur, the dermatologist should be consulted. Depending on the cause and severity of the symptoms, the doctor may consult an internist. If mental problems arise as a result of the skin change, this must be discussed with a therapist or in a self-help group.

Treatment & Therapy

In lentigo maligna, the affected area is usually completely removed. This process takes place as part of an excision. The affected skin tissue is surgically cut out. Not only are the discolorations completely removed, but also the edges of the adjacent skin areas. Sometimes there is talk of a safety distance. The procedure takes place either under local anesthesia or general anesthesia.

As a rule, only limited areas of skin are affected by lentigo maligna. If large areas of skin show discoloration, the defects may be covered with full-thickness skin. If the lentigo maligna is in an inaccessible position, laser therapy may be preferred. Radiation therapy does not usually take place, since this stage is not yet actual cancer.

X-ray irradiation can theoretically be carried out, but should take place with a maximum dose of 100 Gy and only be used in areas that are difficult to access. After the operation, the patients come to follow-up appointments in which the recurrence of the skin changes is ruled out. Sometimes patients choose not to have the discolored areas removed.

This procedure is not recommended because of the high risk of degeneration of atypical melanocytes. A melanoma does not develop for years or even decades, but the sooner the atypical cells are removed, the safer it is. For example, areas of skin that are difficult to reach can hardly be removed after they have degenerated into a lentigo maligna melanoma, since neither laser treatments nor X-rays should take place at this stage.

Outlook & Forecast

If left untreated, lentigo maligna shows an unfavorable course of the disease. As it develops, skin cancer develops. This endangers the life of the person concerned. If no medical help is sought despite the increase in symptoms, the patient dies from the cancer.

With an early diagnosis, an individual treatment plan is drawn up. This provides for the complete removal of the skin changes. The procedure is associated with complications and side effects. Nevertheless, it is the only possibility that brings with it the prospect of freedom from symptoms. If the operation proceeds without further disturbances and incidents, the lentigo maligna is considered to have healed. Nevertheless, the patient must take part in regular check-ups in the long term in order to be able to take immediate treatment measures if the symptoms return.

Due to the optical changes, secondary diseases can occur. There is a state of heightened emotional distress. This can lead to the development of a mental disorder. When making the prognosis, the possibility of secondary diseases must be pointed out, as these contribute significantly to a worsening of the outlook. The prognosis is also worse in patients in whom the skin abnormalities occur in areas of skin that are particularly difficult to access. Removal in these areas of the body is more complex and may result in not removing all of the diseased tissue.


Lentigo maligna can be prevented by avoiding direct exposure to the sun, especially on sensitive skin areas.


As part of the follow-up care, it is important to keep the affected skin areas clean and to avoid skin irritation from clothing or excessive touching if possible. In general, after consultation with the doctor, a healing ointment with the active ingredient panthenol can be applied to accelerate the regeneration of the skin. Products containing cortisone should not be used, as these would abolish the desired inflammatory process that is necessary for the treatment of lentigo maligna.

If the skin changes are removed with the help of cryotherapy or surgically, small wounds also remain, which must be protected from contamination and kept dry until they have healed. The most important aftercare measure is lifelong sun protection of the endangered skin areas with the help of appropriate clothing and sunscreen.

In order to protect the particularly sensitive scalp and facial skin, those affected should always wear a sun hat or cap when the sun is shining. Regular self-checks of the skin and six-monthly to annual checks by the dermatologist ensure that newly occurring lentigo maligna can be treated at an early stage.

You can do that yourself

Individuals found to have lentigo maligna should undergo excision. Careful wound care must be ensured after such an operation, as there is an increased risk of infections and wound healing disorders. Should such complications arise, the doctor must be informed. Otherwise, the lentigo maligna can form recurrences and possibly even cause cancer.

In addition, sufferers should pay careful attention to other, mostly non-specific symptoms. Pain in the affected area indicates a malignant disease. Regular check-ups should be carried out after surgery to ensure that the skin changes do not recur. Patients who choose not to have the diseased skin area removed should have regular cancer screening, as there is a relatively high risk of degeneration.

In some cases, the discolored areas can be treated with alternative remedies. Citrus acid, for example, has proven its worth and, if used regularly, lightens the skin. Homeopathic remedies can also be tried in consultation with the doctor. As a rule, however, the doctor will recommend conservative treatment, which can be supported by those affected by rest and strict hygiene in the affected areas.