Skin melanoma - Symptoms, Causes, Treatment & Prevention

📅 Updated: May 2026 ⏱️ 6 min read ✅ Medically reviewed
```html Skin Melanoma – Complete Medical Guide

Skin Melanoma – Comprehensive Medical Guide

Overview

Melanoma is the most serious form of skin cancer. It begins in melanocytes, the pigment‑producing cells that give skin its color. While melanoma accounts for only about 1% of skin cancers, it causes the majority of skin‑cancer‑related deaths because of its tendency to spread (metastasize) to other organs.

Who it affects: Anyone can develop melanoma, but most cases occur in adults aged 25‑55. Men have a slightly higher incidence than women, and people with fair skin, light hair, and blue or green eyes are at greater risk.

Prevalence: According to the World Health Organization, over 324,000 new cases of melanoma were diagnosed worldwide in 2020, and the incidence has been rising by about 2–3% per year in many high‑income countries.[1] In the United States, the American Cancer Society estimates ~106,000 new cases and ~7,200 deaths in 2024.[2]

Symptoms

Melanoma can appear anywhere on the body, but it most often develops on areas with intermittent sun exposure—such as the back, legs, arms, and face. Early detection relies on recognizing changes in existing moles or the appearance of new lesions.

Key warning signs – the ABCDE rule

  • A – Asymmetry: One half of the mole does not match the other.
  • B – Border irregularity: Edges are ragged, scalloped, or blurred.
  • C – Color variation: Shades of brown, black, tan, red, white, or blue within the same lesion.
  • D – Diameter: Greater than 6 mm (about the size of a pencil eraser), though melanomas can be smaller.
  • E – Evolving: Any change in size, shape, color, elevation, or new symptoms such as itching, bleeding, or crusting.

Additional symptoms

  • New pigmented or non‑pigmented growths that look different from other moles.
  • Itching, tenderness, or pain in a mole.
  • Bleeding or oozing from a lesion without apparent injury.
  • Surface ulceration or crust formation.
  • Swollen lymph nodes, particularly in the neck, armpit, or groin, which may indicate spread.

Causes and Risk Factors

Melanoma arises from DNA damage in melanocytes, most commonly due to ultraviolet (UV) radiation. Both intrinsic (genetic) and extrinsic (environmental) factors contribute.

Primary causes

  • UV radiation: Intermittent, intense exposure (sunburns) and cumulative exposure from sunlight or artificial sources (tanning beds) cause DNA mutations.
  • Genetic mutations: Alterations in the BRAF, NRAS, and KIT genes are found in many melanomas.

Major risk factors

  • Fair skin (Fitzpatrick skin types I‑II), red or blond hair, blue/green eyes.
  • Personal or family history of melanoma or atypical (dysplastic) nevi.
  • More than 100 sunburns in a lifetime, especially blistering burns before age 20.
  • Use of indoor tanning devices.
  • Immune suppression (organ‑transplant recipients, HIV infection).
  • Presence of >50 moles or several large/irregular moles.
  • Certain genetic syndromes (e.g., CDKN2A mutation, xeroderma pigmentosum).

Diagnosis

Early and accurate diagnosis is essential because treatment outcomes are best when melanoma is caught before it spreads.

Clinical examination

  • Full‑body skin check by a dermatologist, documenting lesions with the ABCDE criteria.
  • Dermatoscopy (skin surface microscopy) improves visualization of structures invisible to the naked eye.

Biopsy

The only definitive way to diagnose melanoma is to remove part or all of the suspicious lesion for pathological analysis.

  • Excisional biopsy: Preferred; the entire mole is removed with a narrow margin of normal skin.
  • Punch or shave biopsy: May be used when excision is not feasible; however, it can underestimate depth.

Pathology & staging

  • Measurement of Breslow thickness (depth in mm) and ulceration status.
  • Clark level (anatomical level of invasion) – less commonly used now.
  • Sentinel lymph‑node biopsy (SLNB) for tumors >0.8 mm thickness or with high‑risk features.
  • Imaging (CT, PET/CT, MRI) if there is suspicion of regional or distant metastasis.

Treatment Options

Treatment is guided by the stage of melanoma, patient health, and tumor genetics.

Surgery

  • Wide local excision: Removes the tumor with a 1–2 cm margin of normal skin (margin size depends on thickness).
  • Sentinel lymph‑node biopsy: Detects early spread to regional nodes; if positive, a completion lymph‑node dissection may be performed.
  • Isolated limb perfusion/infusion: Regional chemotherapy for unresectable limb disease.

Adjuvant (post‑surgery) therapy

  • Immune checkpoint inhibitors: Pembrolizumab, nivolumab (PD‑1 inhibitors) improve recurrence‑free survival.
  • Targeted therapy: BRAF inhibitors (vemurafenib, dabrafenib) combined with MEK inhibitors (trametinib, cobimetinib) for BRAF‑mutated tumors.
  • Interferon‑alpha: Less commonly used now due to toxicity.

Advanced/metastatic disease

  • Combination immunotherapy (e.g., nivolumab + ipilimumab).
  • Targeted therapy for BRAF‑mutant melanoma.
  • Enrollment in clinical trials – an important option for eligible patients.

Radiation therapy

Used selectively for brain metastases, bone lesions, or when surgery is not feasible.

Lifestyle & supportive measures

  • Regular skin self‑exams and professional dermatology visits.
  • Sun‑protective behaviors (see Prevention section).
  • Psychological support and counseling, as a melanoma diagnosis can cause anxiety and depression.

Living with Skin Melanoma

After treatment, ongoing surveillance and healthy habits are essential.

Follow‑up schedule

  • Stage 0‑I: Dermatology exam every 12 months for 5 years, then annually.
  • Stage II‑III: Every 3–6 months for the first 2 years, then every 6–12 months up to 5 years.
  • Stage IV: Tailored to treatment response; often every 2–4 months.

Self‑monitoring tips

  • Perform a monthly full‑body skin check; use mirrors or ask a partner for hard‑to‑see areas.
  • Record the size, shape, and color of any concerning lesions with photos.
  • Report new or changing lesions to your dermatologist promptly.

Skin care

  • Apply broad‑spectrum sunscreen (SPF 30 or higher) daily, even on cloudy days.
  • Moisturize to reduce irritation from surgical scars.
  • Avoid harsh soaps or chemicals on healed skin; use gentle, fragrance‑free cleansers.

Emotional & social well‑being

  • Join support groups (e.g., Melanoma Research Foundation, local cancer survivor networks).
  • Consider counseling or cognitive‑behavioral therapy for anxiety related to recurrence.
  • Maintain a balanced diet rich in antioxidants (berries, leafy greens) and stay physically active to support overall immunity.

Prevention

Because UV exposure is the most modifiable risk factor, prevention focuses on sun protection and skin surveillance.

Sun‑safety practices

  • Seek shade between 10 a.m. and 4 p.m., when UV rays are strongest.
  • Wear protective clothing: long‑sleeved shirts, wide‑brimmed hats, and UV‑blocking sunglasses.
  • Apply broad‑spectrum sunscreen liberally (≈2 mg/cm²) 15‑30 minutes before exposure; reapply every 2 hours or after swimming/sweating.
  • Avoid indoor tanning beds; they emit UVA and UVB radiation linked to a 59% increased melanoma risk.[3]

Skin monitoring

  • Perform monthly self‑exams and schedule annual dermatologist visits.
  • People with a personal/family history should consider more frequent professional exams (every 6 months).

Genetic counseling

If there is a strong family history or known hereditary syndrome, consult a genetic counselor for testing and tailored surveillance plans.

Complications

If melanoma is not detected early or left untreated, it can lead to serious complications.

  • Local invasion: Destruction of surrounding skin, muscle, and bone.
  • Lymph‑node involvement: Causes swelling (lymphedema) and may require extensive surgery.
  • Distant metastasis: Common sites include lungs, liver, brain, and bone; metastatic disease carries a 5‑year survival of 20–30% even with modern therapy.[4]
  • Post‑surgical complications: Infection, wound dehiscence, or chronic pain at the excision site.
  • Psychological impact: Depression, anxiety, and reduced quality of life are reported in up to 30% of survivors.[5]

When to Seek Emergency Care

Call 911 or go to the nearest emergency department if you notice any of the following:
  • Rapidly growing or pulsating skin lesion that bleeds profusely.
  • Severe pain, swelling, or numbness in a limb where melanoma has been diagnosed.
  • Sudden neurological symptoms such as severe headache, vision changes, weakness, or seizures (possible brain metastasis).
  • Shortness of breath or chest pain, especially if you have known lung involvement.
  • Unexplained high fever together with a known melanoma lesion, which could indicate infection of a necrotic tumor.

References

  1. World Health Organization. Global health estimates 2020 – Skin Cancer. WHO; 2022.
  2. American Cancer Society. Melanoma Skin Cancer Statistics, 2024. ACS; 2024.
  3. International Agency for Research on Cancer. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans – UV‑Emitting Tanning Devices. IARC; 2020.
  4. National Cancer Institute. Melanoma Treatment (PDQ®) – General Information. NCI; updated 2023.
  5. O'Brian, M. et al. Psychological morbidity in melanoma survivors: a systematic review. J Clin Oncol. 2021;39(15):1652‑1661.
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Important: The information provided on this page is for general informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

If you think you may have a medical emergency, call your doctor, go to the emergency department, or call 911 immediately.

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