Melanoma

What is melanoma?

Melanoma is a cancer of melanocytes, the pigment producing cells of the skin. It is far less common than other skin cancers but causes the majority of skin cancer deaths because it can spread early. Caught while thin and confined to the skin, it is usually curable by excision alone, which makes early recognition genuinely life saving.

Causes

• Ultraviolet damage to melanocyte DNA
• Intense intermittent sun exposure and sunburn
• Sunbed use
• Genetic mutations including CDKN2A in familial cases
• Large numbers of atypical moles

Symptoms

• A new mole or a change in an existing one
• Asymmetry of shape
• Irregular or poorly defined border
• Uneven colour with several shades
• Diameter usually over 6 millimetres
• Evolution in size, shape, colour or sensation
• Itching, bleeding or crusting of a lesion
• A dark streak under a nail

Risk factors

• Fair skin that burns easily
• History of severe or blistering sunburn
• Many moles or atypical moles
• Family history of melanoma
• Sunbed use, particularly before age 35
• Immunosuppression
• Previous skin cancer

Diagnosis

• ABCDE assessment of suspicious lesions
• Dermoscopy by a trained clinician
• Excision biopsy with histological Breslow thickness
• Sentinel lymph node biopsy for staging in selected cases
• CT or PET imaging for advanced disease
• BRAF mutation testing to guide therapy

Treatment

• Wide local excision, curative for most early melanoma
• Sentinel node biopsy and lymph node management
• Immunotherapy with checkpoint inhibitors for advanced disease
• BRAF and MEK targeted therapy where mutations are present
• Radiotherapy in selected situations
• Long term skin surveillance and self examination
• Rigorous sun protection and avoidance of sunbeds

Self care

• Check your skin monthly and photograph moles to track change
• Use the ABCDE guide for suspicious lesions
• Use broad spectrum SPF 30 or higher daily and reapply
• Avoid sunbeds entirely
• Seek shade between 11am and 3pm
• Attend all surveillance appointments after treatment
• Ask a partner to check areas you cannot see

When to see a doctor

Book an appointment if:

• A new mole or one that is changing
• A mole that looks different from your others
• Itching, bleeding or crusting of a mole
• A dark streak appearing under a nail
• A sore that will not heal
• Family history of melanoma, to arrange surveillance

Some symptoms need emergency care rather than an appointment. See the warning signs listed above.

Prevention

• Avoid sunburn, particularly in childhood
• Never use sunbeds
• Use sunscreen and protective clothing consistently
• Check skin regularly and know your own moles
• Attend surveillance if you have many atypical moles
• Be vigilant if you have a personal or family history

Outlook

Melanoma caught early while thin and confined to the skin is usually cured by excision alone, with five year survival above 95 percent. Prognosis falls substantially once it spreads to lymph nodes or distant organs, though immunotherapy and targeted therapy have transformed outcomes in advanced disease over the past decade.

Related conditions

Common questions