The most common malignant tumor of melanocytic origin in the white population, characterized by its early-stage development, spreading along the surface of the skin. Superficially spreading melanoma accounts for 70% of melanoma cases among the white population and 60% of all melanoma types. The disease typically occurs between the ages of 30 and 50 and is more common in women.

On apparently unchanged skin, a spot (or a flat papule) appears with a diameter of 2-3 mm, gradually increases in size. The affected area becomes oval or irregular in shape, often with one or more depressions. Gradually, thickening occurs, forming an asymmetrical plaque with clear borders, evenly raised above the surface of the skin. The average diameter is 8-12 mm, with early formations ranging from 5 to 8 mm and more advanced ones from 10 to 25 mm.

As the tumor grows, the surface of the affected area becomes uneven, bumpy, crusted, easily injured, bleeding, and nodules may develop. The coloration includes a combination of brown, dark brown, blue, black and red colors, with areas of regression appearing gray or bluish gray.

It can occur anywhere on the body. The most common site is the upper back in both men and women, with the shin area in women and the front of the thighs and torso in men. The tumor takes 1-2 years to develop.

It occurs in about half of cases in people over the age of 65 and is most common in European people with skin types I, II, and III. It accounts for 5-10% of all cutaneous melanoma cases.

Lentigo maligna, which serves as a precursor to lentigo melanoma, initially appears as a single, flat spot with uneven color in various shades of brown and black. The appearance of papules or nodules on the surface of the spot indicates the invasion of tumor cells into the dermis and the progression of the condition to the next stage - lentigo melanoma. This process can take several years, sometimes up to 10-20 years.

The affected area takes on an irregular shape, resembling a geographic map with "peninsulas" with irregular borders ranging in size from 3 to 20 cm or more. Papules or nodules of dark brown, black, and sometimes pinkish or white-gray regression areas are observed on the surface of the flat spot, along with blue patches (accumulations of melanocytes in the dermis).

This new growth is most commonly found on exposed areas of the skin such as the face, neck, forearms, backs of the hands, and shins.

Nodular melanoma accounts for about 14 to 20% of all melanoma cases. It primarily affects Europeans in middle age. Development of the tumor on clear skin or from a pigmented nevus takes between 6 and 18 months.

Nodular melanoma begins its development immediately with the vertical growth phase. The tumor is uniformly elevated above the skin surface and appears as a thick plaque. In cases of exophytic growth, it forms a protruding round nodule resembling a "blueberry" or a polyp. Typically, the color is uniform, dark blue or bluish black, although polypoid growths can sometimes be pink (non-pigmented) with a brownish coating.

In early stages, the affected area measures 1-3 cm, but it can grow over time. The melanoma has a regular, oval, or circular shape with clear borders. Over time, surface of the tumor may become ulcerated and covered with a bloody crust. Black nodules (metastatic foci) often appear around the melanoma.

It is most often found on parts of the body that are relatively less exposed to sunlight. In women, it is often found on the shins.

Acral melanoma manifests on the palms, soles, and fingers. It is characterized by a slowly growing, irregularly shaped spots with clear or blurred borders, uneven coloring in shades of brown, black, and blue, and a size of up to 8-12 cm. Areas of regression (light gray areas) may also be observed.

Subungual melanoma occurs in the nail bed and develops from the nail matrix. It is found in people between the ages of 20 and 80 (with an average age of 55). It accounts for approximately 2.5 to 3.5% of skin melanomas.

Fingers are twice as likely to be affected as toes, with the thumb involved in 80% of cases, possibly due to increased susceptibility to trauma and exposure to ultraviolet radiation. On the soles, subungual melanoma is also predominantly localized on the thumb, less frequently on the II and III digits.

It is characterized by a subungual spot or longitudinal brown or dark-blue stripes associated with pigmentation of the cuticle. Gradually, the nail plate in the pigmented area deteriorates and separates. In its place there is rapid growth of granulations, sometimes mushroom-shaped, bluish-black in color, with infiltration of the underlying and surrounding tissues. A pathognomonic sign associated with the late stage of melanoma is Hutchinson's sign (pigmentation in the area of the posterior eponychium).

The course of melanoma on the toes is generally less aggressive than on the fingers.

Oral melanoma accounts for 2.5% of all melanomas. It is four times more common in men than in women. In the radial growth phase, the tumor appears as an irregularly shaped dark brown or black spot, while in the vertical growth phase it develops into a solid nodule. There are no established risk factors for this tumor. The most common sites of involvement are the hard palate, buccal mucosa, and less commonly the lips and gums.

Ocular melanoma is the second most common type after cutaneous melanoma and the most common primary intraocular malignancy in adults. It includes the most common form, uveal melanoma, which involves the iris, ciliary body, or choroid, and the rarer conjunctival melanoma. Clinically, there is an irregularly shaped dark brown or black spot in the iris or conjunctiva. It often metastasizes and the five-year survival rate is approximately 15%.

A very rare form of melanoma, accounting for 0.9% of all melanomas. The primary focus is typically localized on the glans or distal part of the penile head in the form of irregularly shaped patches and plaques, dark brown or black in color. It rapidly metastasizes to the inguinal and pelvic lymph nodes.

Vulvar melanoma accounts for 3 to 6% of all melanomas. It more commonly occurs in women over 60 years old but can also be found in young women and girls. Predisposing factors include tissue atrophy, degeneration, dystrophy, disceratosis, scleroatrophic lichen, melanocytic nevi, and trauma. Clinically, it presents as flat irregularly shaped spots, papules, nodules, dark brown, or black in color. The most common sites are the labia minora and clitoris, less commonly the labia majora and vaginal vestibule.

The incidence of anorectal melanoma is 1.0 to 1.5% of all melanomas and 0.25 to 1.8% of all malignancies at this site. It occurs in various age groups, but is more common in individuals between the ages of 40 and 70. Symptoms are non-specific, with the most common being blood in the stool and pain in the anal region. Clinically, anorectal and perianal melanomas present as flat, irregularly shaped spots, papules, or nodules that are dark brown or black in color, occasionally cherry red. Depigmented areas and nonpigmented forms are often observed. This type is characterized by early lymphatic and hematogenous metastasis to the inguinal lymph nodes, liver, lungs, bones, and distant areas of the body.

An amelanotic melanoma, a malignant melanocytic tumor with an absence of melanin. Frequency - 1.8%. It occurs in 65-70% of cases in women over the age of 50. It may begin as a pink papule that rapidly increases in size. It presents as a dense, amelanotic, lightly pigmented, reddish-blue or pinkish-blue nodule. As it breaks down, it forms an ulcer with firm, raised edges and a papillomatous base. It can occur anywhere, but is more common on the fingers, soles, and heels.

Desmoplastic melanoma is a malignant melanocytic tumor that clinically resembles amelanotic melanoma but has distinctive histological features. Desmoplastic melanoma may arise from lentigo maligna, less commonly from acral lentiginous or superficial spreading melanoma. It occurs in people between the ages of 30 and 90 (average age 56), more often in women with skin phototypes I, II, and III. The growth is slow. In its early stages it appears as an unevenly pigmented spot resembling lentigo, sometimes with tiny bluish-grey nodules on its background. In its later stages, it becomes a firm, typically amelanotic or lightly pigmented nodule. In 85% of cases it is found on the head and neck, most commonly on the face, occasionally on the trunk, hands and feet.

Neurotropic melanoma is a malignant melanocytic tumor associated with pathologic changes in the nerve trunks. It is clinically indistinguishable from desmoplastic melanoma, but shows signs of neuropathy when it spreads significantly, typically affecting cranial nerves, especially the trigeminal and facial nerves.

Childhood melanoma is categorized into infantile melanoma (from birth to one year of age), childhood melanoma (from one year to the onset of puberty), and adolescent melanoma (from 13 to 16 years of age).

In 50-92% of cases, childhood melanoma develops at the site of congenital giant melanocytic nevi during the first five years of life, with an estimated lifetime risk of developing melanoma of 6-7%.

In healthy skin, melanoma in children practically does not develop. In some cases, tumors may develop in children with dysplastic melanocytic nevi, a family history of melanoma, pigmentary xeroderma, or after immunosuppression. Familial cases account for approximately 10% of cases and tend to develop at an earlier age. Intense exposure to ultraviolet radiation plays a significant role in the development of melanoma.

Childhood melanoma is rare, accounting for 0.3% of cases in children with other malignancies. It is most commonly observed in children between the ages of 4-6 and 11-15 years. The male to female ratio is approximately 1:1.5.

Melanomas that develop before the age of 16 are most common on the trunk (50%), followed by the lower extremities (20%), head and neck (15%), and upper extremities (15%). Their size can vary from 0.5 to 7 cm or more, especially in melanomas growing from giant pigmented nevi. The appearance of these neoplasms is variable. In 95% of cases, melanomas have a broad base, with colors ranging from black to normal skin tone.

A very rare form of melanoma can develop in three ways: in infants born to mothers with metastatic melanoma (transplacental transmission), primary melanoma arising from a nevus, primary melanoma arising in utero. In addition to skin involvement, it is characterized by metastasis to the liver and brain.

A malignant melanocytic tumor with clinical and pathomorphologic features similar to Spitz nevi, but with an aggressive potential for tumor spread beyond the regional lymph nodes. It typically appears after the age of 30-40 years.

A rare variant of melanoma that is more common in men in the sixth decade of life. Clinically, it is characterized by a dome-shaped papule with a papillomatous surface, larger than 1 cm, resembling intradermal nevi, seborrheic keratosis, and acrochordon. It is often found on the trunk and extremities.

A rare subtype of cutaneous melanoma, but a common form of melanoma in the gastrointestinal tract. It is considered a variant of nodular melanoma. It is characterized by slow radial growth and rapid vertical growth, forming a perpendicular nodular shape on a peduncle ranging in color from pink to dark brown, set against a background of irregularly colored, irregularly shaped patches. The surface of the neoplasm is often crusted and may bleed.

Metastases and recurrences of melanoma can occur in distant areas of the skin as well as in the graft used to cover a defect after removal of the primary tumor. The primary melanoma may be located in the eye, cervix, or oral mucosa. Metastasis of melanoma from an undetected primary site is not uncommon. Metastases are usually nodular and may be single or multiple. They are typically dark in color, but unpigmented forms are also seen.