Melanoma

What is melanoma?

Melanoma is a cancer that develops from melanocytes, the cells that produce melanin, a pigment contributing to the colour of the skin, hair and eyes. In the skin, melanocytes are mainly found in the deepest part of the epidermis. Changes affecting how these cells grow can lead to melanoma.

A mole, or melanocytic naevus, is usually a benign growth. Melanoma can develop within an existing mole, but it can also appear on skin where no lesion was previously visible. Checking only familiar moles is therefore not enough: new spots and skin growths also deserve attention.

Where can it develop?

Most melanomas develop in the skin and are called cutaneous melanomas. They can occur on the trunk, limbs, face and scalp, as well as less easily inspected areas such as the soles, palms and nail unit.

Less commonly, melanoma starts in a mucous membrane or the eye. Exceptionally rare primary melanomas of the central nervous system have also been described. These are different from metastases: melanoma that spreads from the skin to another organ remains metastatic melanoma, rather than a new cancer arising from that organ.

The site matters. Cutaneous, mucosal and ocular melanomas have different biological features and specialist care pathways. Their relationship with ultraviolet radiation also differs. A suspicious lesion cannot be dismissed simply because that area receives little sunlight.

Changes that need assessment

A lesion that changes in shape, colour, size or elevation deserves attention. This may be an existing mole or a new growth that looks different from others. Not all melanomas are dark: some have little pigment and may appear pink or reddish.

The ABCDE rule highlights asymmetry, border, colour, diameter and evolution. It is an observation aid, not a diagnostic test. Melanoma can be smaller than 6 mm and may not show every feature. A growing lesion, spontaneous bleeding, persistent itching or a spot unlike your other moles also warrants attention.

If you notice a change, seek medical assessment without waiting for several warning signs to appear together. Photographs can help document changes, but comparing your skin with pictures online cannot establish whether a lesion is benign.

Who can develop melanoma and what affects risk?

Melanoma can affect people of any skin colour. It is rare in children and becomes more common with age, while also being important among younger adults. Fair skin, light eyes, red or blond hair and a tendency to burn are associated with increased risk, but none is required for melanoma to occur.

Relevant factors include natural or artificial UV exposure, sunburns, numerous or atypical moles, a previous melanoma and family history. Immunosuppression can also increase risk. A doctor considers these factors together when planning appropriate surveillance.

As a dated epidemiological reference, AIRC reports approximately 12,700 new diagnoses in Italy in 2023. This estimate describes that year and population. It is neither an automatically updated figure nor a measure of an individual person’s risk.

From examination to diagnosis: why timing matters

Finding melanoma while it remains localised may allow surgery with curative intent. However, a lesion that looks “superficial” to the naked eye is not necessarily shallow: depth is assessed under a microscope. Individual outcomes depend on tumour features and extent, not simply its appearance.

Assessment includes personal and family history, a skin examination and dermoscopy when appropriate. A suspicious lesion may need a biopsy, often complete removal where feasible. Histology establishes the diagnosis and describes features such as Breslow thickness and ulceration.

The frequency of appointments and any photographic monitoring are tailored to the person. Not every mole needs removal or the same surveillance schedule. If melanoma is confirmed, further investigations are selected according to the clinical situation.

BRAF, molecular research and treatment

Molecular research has changed how melanoma is understood and treated. BRAF is one of the genes involved in signals controlling cell growth. Some cutaneous melanomas have activating mutations in this gene. Among variants at position 600, V600E means that valine is replaced by glutamic acid; other variants include V600K.

Not all melanomas have a BRAF mutation. When the result could guide treatment, the care team may request testing of tumour tissue. Molecular testing does not replace histological diagnosis, and results must be interpreted in their clinical context.

Vemurafenib, mentioned in earlier versions of this page, is a BRAF-targeted drug. Treatment options now include combinations of BRAF and MEK inhibitors in suitable cases, as well as immunotherapy. Surgery, systemic treatments and other interventions have different roles depending on stage, tumour biology and the person’s health. There is no single treatment appropriate for everyone.

Skin protection and check-ups

Limiting excessive UV exposure is a practical preventive measure. Seek shade, wear protective clothing, a hat and sunglasses, and apply broad-spectrum sunscreen according to the product instructions. Sunscreen does not make prolonged exposure safe and should be combined with other protection. Avoid tanning lamps and sunbeds.

Knowing your skin helps you notice changes, including in less visible areas. Self-examination complements medical assessment rather than replacing it. Sun protection reduces an important risk factor but cannot eliminate every possibility of melanoma. Prevention and attention to changes therefore belong together.

Types of melanoma: finding your way through the site

Melanoma includes different forms. The main cutaneous types include superficial spreading melanoma, nodular melanoma, lentigo maligna melanoma and acral lentiginous melanoma. Some names mainly describe a body site, while others describe clinical or microscopic features. They are not all equivalent categories.

For example, “amelanotic” refers to little or no pigment, whereas “metastatic” describes spread of the disease, not a form identifiable by colour alone. The type is not the same as the stage. The site provides three collections for further reading: common types, rare variants and forms affecting particular sites.

• Common types
• Rare variants
• Particular sites and types