As the Dermatologist – Venereologist Dr. Amalia Tsiatoura explains “melanoma comes from the melanin cells of the skin and it is possible to appear either in a pre-existing mole, or “de novo”, i.e. in an area that was previously healthy. Although it has a lower incidence rate than other forms of skin cancer, it is extremely dangerous because it most often metastasises to other organs or tissues.
Most often, it occurs in areas that have been chronically exposed to the sun, as it has been observed that in almost half of the cases melanoma is found in the upper or lower limbs. Several times it is also found on the head, mainly on the face or ears. However, melanoma can also occur in non-exposed areas such as the palms, soles and perineum.
Melanoma looks like a nevus or papule with a different morphology than usual. Its colour can vary from black, blue, dark brown or grey and in more advanced lesions it may start to swell and become thicker. Symptoms that may accompany it are itching, bleeding and epithelialisation (crusting).
Melanoma of the skin can occur at any age, with a higher incidence in people aged 40-60 years. However, in recent years there has been an increase in cases in younger people. As the factors that favour its development are skin type and exposure to sunlight, people with fair skin, freckles, nevus, a family history of melanoma and people who are frequently exposed to the sun or have received radiation therapy are at increased risk of developing it.
The incidence of melanoma is particularly high in countries with increased solar radiation, such as Greece. Often, melanoma occurs in people with immunodeficiency or people who have undergone chemotherapy.
Clinically suspicious signs of melanoma are the following:
- Change in shape, colour and/or size of a lesion
- Asymmetry or abnormal boundaries of the area
- Bleeding or crusting
- Change in colour or appearance of several colours within a single nevus
- Area diameter greater than 6mm
- Existence of an overgrown area on a previously flat nevus
- Ulceration and itching may indicate malignant exudation
Due to the aggressiveness and rapid growth of this neoplasm, it is very important to detect it as soon as possible. For this reason, moles (olives) should be examined by a qualified Dermatologist at least once a year and he will judge whether Dermoscopy or Mole Mapping is required, in order to have a detailed follow-up.
Melanoma can be diagnosed by removing part or all of the skin lesion and examining its cells under a microscope (biopsy). Often the histological differential diagnosis of the lesion requires immunohistochemistry with special stains applied by the pathologist to distinguish the neoplastic cells. Histological examination is the basis for the diagnosis and treatment of melanoma.
If melanoma is suspected, the lesion should be removed surgically, in its entirety and as soon as possible, and a biopsy (microscopic examination) should be performed. These lesions should not be treated with laser or other methods (e.g. transthermal coagulation or cryotherapy) because this destroys the tissue and valuable information for the diagnosis of the neoplasm, its depth and staging is lost.
In which parts of the body does melanoma occur?
Melanoma in men occurs most often on the trunk, head and neck. In women, it occurs mainly on the arms or shins. In addition to the skin, melanoma occurs less frequently in the mucous membranes (mouth, vagina) and in the eye. Although it occurs more frequently in people of the white race, the occurrence of melanoma in people of the black race cannot be excluded, with the palms and soles being the most frequent sites of occurrence.
What are the types of melanoma?
Intraepidermal Epidermotropic Metastatic Melanoma: It usually appears as a melanotic spot on the skin of the body. It occurs mainly in young people and the face is the most common site. It is considered an early form of in situ melanoma.
Lentigo Maligna Melanoma: Its occurrence is more common in older people and in places that have been exposed to sunlight for years. It appears as a flat melanchromatic lesion, which increases in size over time. Initially it extends horizontally, and at a later stage it begins to extend vertically. At this stage it forms the malignant invasive melanoma. It can take on colourations from white or grey, to dark brown or black.
Superficial Spreading Melanoma: The initial appearance of this melanoma is a flat spot that slowly turns into a papule. It is characterised by the formation of nodules as it expands into the deeper layers of the skin and the appearance of a brown, black, grey or white colour. It has an irregular periphery and extends horizontally.
Nodular Melanoma: It starts as a papule and turns into a nodule and subsequently, it progresses and bleeds. It appears on the skin in the form of a shiny, usually black lump and mainly affects men. It should be diagnosed quickly because in the nodule stage, it already starts to metastasize.
Malignant melanoma of the extremities: It is seen on the feet (mainly the soles), on the palms or under the nails (subcutaneous melanoma). The clinical picture is characterised by the appearance of a black irregular line under the nail and redness and swelling near the skin (Hutchinson’s sign). On the palms and soles it looks like a nevus. During the progression of this melanoma, the person may experience pain, or notice ulceration and bleeding.
Desmoplastic Melanoma: It is the rarest form of melanoma and occurs mostly in older people. It occurs due to the formation and accumulation of nodules or plaque. It mainly affects the face and neck. Unfortunately, it is the most difficult form of melanoma to treat, as most of the time, once it appears, it cannot be cured.
Amelanotic Malignant Melanoma: It may resemble a scar, pyogenic granuloma or hemangioma and is usually colorless, although in some cases it shows a characteristic pinkish tint.
What are the stages of melanoma?
By staging we mean the process that is followed to determine the extent of the disease and is a crucial stage in the treatment of the disease. According to Clark’s classification, melanomas are divided into five levels of infiltration, depending on the depth of the skin to which the melanoma has spread. These stages are as follows:
- Stage 1: the melanoma is localized to the membrane of the epidermis, at the junction of the epidermis and the dermis.
- Stage 2: the melanoma extends into the papillary layer of the chorion.
- Stage 3: extension of the melanoma to the boundary between the papillary and reticular layers of the chorion.
- Stage 4: infiltration of the reticular layer.
- Stage 5: infiltration of subcutaneous tissue, including adipose tissue.
Melanomas that are in stage 1 are almost always curable by surgical removal. At stage 2, the chance of recurrence is 60%, while melanomas detected at stage 3 or 4 have been shown to recur in 85% of cases. The treatment of melanoma is mainly surgical. Treatment should be immediate as it expands relatively quickly and metastasizes in a short time. Surgical removal of melanoma should include removal of at least 2 cm of healthy tissue peripherally.
How is melanoma treated?
If melanoma is suspected, the lesion should be surgically removed as soon as possible and then examined under a microscope (biopsy).
These lesions should not be treated with laser or other destructive methods (e.g. transthermal coagulation or cryotherapy) because this way the tissue is destroyed and valuable information for the diagnosis of the neoplasm, its depth and staging is lost.
In addition to surgical removal of the melanoma, sometimes the following are also indicated:
- Radiotherapy: for large lesions, especially in older people, or in local metastases to relieve symptoms.
- Cryosurgery: to treat secondary skin metastases.
- Chemotherapy: with specific chemotherapeutic drugs.
- Immunotherapy: with specific agents targeting the immune system.
- Thermotherapy: a type of cancer treatment in which skin tissues are exposed to high temperatures. The presence of high temperatures can “kill” cancer cells and fight the affected tissues. It is a particularly effective method of fighting melanoma.
After removal of the melanoma, what comes next?
After the treatment and removal of the melanoma, the patient must visit the dermatologist at regular intervals. Regular follow up every 3 months is recommended for at least 3 years after removal.
Who has an increased risk of developing melanoma?
People at high risk should have their moles checked regularly. Risk factors for developing melanoma are:
- Light-skinned people (Phototype I)
- Existence of multiple (>50) or dysplastic – malformed nevus on the skin
- Existence of congenital nevus
- History of malignant melanoma in the family
- Multiple papules or freckles on the skin of the face, hands and body
- Intense intermittent sun exposure (e.g. in the summer months)
- History of sunburn during childhood
- Intense exposure to artificial sources of UV radiation (e.g. tanning beds)
What happens in case of a positive biopsy for melanoma?
If the result of the biopsy is positive, there is an additional wider surgical resection of the neoplasm, lymph node examination and staging of the tumor. In some cases, radiotherapy and chemotherapy may be required.
Superficial Spreading Melanoma and Nodular Melanoma are the most aggressive types of melanoma. Early diagnosis of small superficial lesions may also lead to complete cure, while advanced tumors with metastases may limit the average survival time to 6-9 months.
Is there a chance that the melanoma will reappear?
The treatment of melanoma depends on the stage it is in. In the early stages of melanoma, surgical removal has a fairly high rate of complete cure, up to 98%. However, once the melanoma has reached a depth or has spread sufficiently, there is a risk that it will recur. For this reason, after surgery, the patient is given chemotherapy drugs.
In any case, people who have developed melanoma have an increased risk of developing another melanoma. For this reason, regular monitoring by a dermatologist is recommended.
How can I protect myself from melanoma?
Although the occurrence of melanoma is unpredictable, a person should pay great attention to prevention. Keeping in mind that solar radiation is largely responsible, the person should avoid prolonged exposure to the sun. Furthermore, when exposed to solar radiation, sun creams, hats and sunglasses should be used.
Is melanoma hereditary?
It has been shown that the occurrence of skin cancer, in addition to external factors, is also due to hereditary causes. More specifically, people whose parents or siblings have developed skin cancer are more likely to develop it themselves. The same applies to melanoma. In this case, you should not be alarmed, but be more alert in case you spot a worrying sign.
Is melanoma always malignant?
Melanoma is a type of cancer and is therefore always malignant. In many cases, however, it is the mutation of a benign nevus (mole).