Metastatic Melanoma- An overview

What Is Metastatic Melanoma?

Melanoma develops when melanocytes grow abnormally and uncontrollably. It usually appears on sun-exposed areas of the skin but may also occur under the nails, inside the mouth, or on the soles of the feet.

When melanoma cells spread from the original skin lesion to distant organs, the condition is called metastatic melanoma. As per the American Society of Clinical Oncology (ASCO), around 4 % of melanoma patients already have distant metastasis at diagnosis.

Stages of Metastatic Melanoma

Melanoma is divided into stages based on tumor growth and spread.

• Stage 0: Cancer remains limited to the outer skin layer.

• Stage 1 and 2: Localized melanoma without distant spread.

• Stage 3: Spread to nearby lymph nodes or tissues.

• Stage 4: Spread to distant organs such as the lungs, liver, brain, or bones.

AJCC Stage IV Subclassification

Doctors further divide stage IV melanoma into substages:

• M1a: Spread to distant skin or lymph nodes.

• M1b: Spread to the lungs.

• M1c: Spread to organs other than the lungs.

• M1d: Spread to the brain or spinal cord.

LDH Blood Test

Serum lactate dehydrogenase (LDH) is a blood marker used in staging metastatic melanoma. High LDH levels may indicate aggressive disease and poorer survival.

How Does Metastatic Melanoma Develop?

Ultraviolet (UV) radiation from sunlight or tanning beds damages the DNA (Deoxyribonucleic acid) in skin cells. Repeated damage may cause melanocytes to become cancerous.

The cancer may first remain localized to the skin. Later, melanoma cells can travel through blood vessels or lymphatic channels and spread to distant organs. Sometimes the original lesion may be very small and unnoticed until metastatic symptoms appear.

Risk Factors for Melanoma

Several factors increase the risk of melanoma:

• Fair skin and light-colored eyes.

• Frequent sunburns during childhood.

• Excessive sun exposure.

• Tanning bed use.

• Family history of melanoma.

• Multiple atypical moles.

• Weak immune system.

• Certain genetic mutations.

Risk Factors for Metastatic Melanoma

Certain factors increase the risk of melanoma spreading to distant organs:

• Nodular melanoma subtype (Fast-growing raised melanoma).

• Ulcerated melanoma lesions (Melanoma with broken skin).

• Thick primary tumors.

• Delayed diagnosis or untreated melanoma.

• Spread to nearby lymph nodes.

• Male sex, which is associated with a slightly higher risk of metastatic melanoma.

What Are the Symptoms of Metastatic Melanoma?

Melanoma often starts as a suspicious mole or dark skin patch. Early detection improves treatment success.

ABCDE Rule for Melanoma

The ABCDE rule helps identify warning signs:

• A - Asymmetry: One half looks different from the other.

• B – Border: Uneven and irregular border.

• C – Color: Variations in color like dark brown, black, red, and blue.

• D – Diameter: Greater than 6 millimeters or growing larger.

• E – Evolving: Changes that include growth, change in shape, and variations in color, itchiness, and bleeding.

General Symptoms

• Weight loss.

• Fatigue.

• Loss of appetite.

• Weakness.

• Swollen lymph nodes.

• Symptoms Based on the Organ Affected

• Lung Metastasis

• Chest pain.

• Nausea and vomiting.

• Breathing issues.

• Cough.

• Coughing up blood.

• Liver metastasis.

• Abdominal swelling.

• Jaundice.

• Enlarged liver.

• Loss of appetite.

• Brain Metastasis

• Headaches.

• Nausea and vomiting.

• Seizures.

• Memory loss.

• Vision changes.

• Weakness or paralysis.

• Bone Metastasis

• Bone pain.

• Easy fractures.

• Tingling or numbness.

• Confusion due to high calcium levels.

How Is Metastatic Melanoma Diagnosed?

1. Skin Biopsy

A biopsy confirms melanoma by examining tissue under a microscope. Common biopsy methods include:

• Punch Biopsy: A small, circular tool is used to remove a deep sample of the skin, including all layers, for examination under a microscope.

• Excisional Biopsy: The entire suspicious mole or skin lesion is surgically removed along with a small margin of surrounding healthy skin.

• Shave Biopsy: To analyze abnormal cells, the top layers of the skin lesion are gently shaved off with a razor.

2. Sentinel Lymph Node Biopsy (SLNB)

This test checks whether melanoma has spread to nearby lymph nodes using a dye or radioactive tracer.

3. Imaging Tests

Doctors may use:

• Computed tomography scan.

• Magnetic resonance imaging scans.

• Positron emission tomography scan.

• Ultrasound.

4. Blood Tests:

The blood test checks on one’s general health as well as levels of LDH because high amounts of LDH in the blood can indicate injury to the cells.

5. Genetic Testing:

About half of melanoma patients have BRAF gene mutations. BRAF testing helps doctors decide whether targeted therapy is suitable.

What Is the Treatment for Metastatic Melanoma?

Treatment depends on the stage, spread, genetic mutations, and overall health.

Local Treatments

• Surgery: Surgery removes the primary tumor, nearby lymph nodes, or isolated metastatic tumors.

• Radiation Therapy: Radiation therapy destroys cancer cells and helps manage symptoms such as pain and brain-related issues.

Systemic Treatments

• Immunotherapy: It helps the immune system target and destroy cancer cells. Common drugs include:

  • Ipilimumab.

  • Nivolumab.

  • Pembrolizumab.

  • Opdualag.

  • PD-1 inhibitors, such as Nivolumab and Pembrolizumab, enhance the immune response against melanoma cells.

• Targeted Therapy: Targeted therapy is used mainly in patients with BRAF mutations.

BRAF-Inhibitors: Dabrafenib, Encorafenib, Vemurafenib.

MEK Inhibitors: Binimetinib, Cobimetinib, Trametinib.

These drugs are often used together for better results.

• Chemotherapy: Chemotherapy is less commonly used today because immunotherapy and targeted therapy are usually more effective.

• Palliative Care: Palliative care improves comfort and quality of life. It helps manage pain, fatigue, breathing difficulty, emotional stress, and treatment side effects. It can be given along with cancer treatment.

Side Effects of Treatment

Immunotherapy side effects are as follows:

• Skin rash.

• Diarrhea.

• Hormonal problems.

• Fatigue.

• Liver inflammation.

Targeted Therapy Side Effects

• Fever.

• Joint pain.

• Muscle aches.

• Skin sensitivity.

Chemotherapy Side Effects

• Nausea and vomiting.

• Hair loss.

• Increased infection risk.

• Treatment-Related Complications

Some patients may develop:

• Lymphedema.

• Peripheral neuropathy.

• Chemo brain or memory problems.

• Chronic fatigue.

• Increased infections.

Taking Care of Yourself During Treatment

Lifestyle changes may improve well-being during treatment:

• Avoid excessive sun exposure.

• Use sunscreen daily.

• Eat healthy meals.

• Stay physically active.

• Attend regular follow-up visits.

• Seek emotional support.

• Avoid smoking and alcohol.

Clinical Trials

Clinical trials help develop newer melanoma treatments. Some patients may benefit from participating in clinical studies if standard treatments are ineffective. Metastatic melanoma clinical trials also explore next-generation immunotherapies such as tumor-infiltrating lymphocyte (TIL) therapy and oncolytic virus therapy, targeted mutation inhibitors, and combination treatments for unresectable Stage III or Stage IV melanoma. These studies may provide access to advanced therapies that are not yet widely available.

Questions to Ask the Doctor

Patients may ask:

• What stage is the melanoma?

• Has it spread to other organs?

• Is BRAF testing needed?

• Which treatment is best?

• What side effects may occur?

• Are clinical trials available?

• Is palliative care needed?

• What symptoms should be monitored?

• What are the chances of recurrence?

• How often are follow-up scans required?

Prognosis and Survival Rate

• The prognosis depends on factors such as stage, organ involvement, LDH levels, and response to treatment.

• The five-year survival rate with current treatments in metastatic melanoma is about 35%.

• The survival rate for regional spread of melanoma (lymph node involvement) is about 66%.

• Immunotherapy and newer targeted agents have revolutionized treatment.

• In 2024, melanoma-related deaths were estimated at around 8,290 cases in the United States.

Conclusion

Metastatic melanoma refers to the spreading of skin cancer to other body parts like the lungs, liver, brain, and bone. Metastatic melanoma can be detected early using the ABCDE rule.

Diagnosis usually involves biopsy, imaging tests, blood tests, and genetic testing. Modern treatments such as immunotherapy, targeted therapy, surgery, and radiation therapy have improved survival rates. Palliative care, supportive care, and clinical trials also play an important role in treatment and quality of life. For further information, consult a cancer specialist.

Key Takeaways

• Metastatic melanoma is an advanced skin cancer that spreads to organs such as the lungs, liver, brain, and bones.

• The ABCDE rule helps identify suspicious moles early and improves the chances of successful treatment.

• Diagnosis includes biopsy, scanning, blood tests, and BRAF mutation testing.

• Immunotherapy and targeted therapies have revolutionized the outcomes of metastatic melanoma patients.

• Palliative care, lifestyle modifications, and follow-ups are essential to improve the quality of life of patients undergoing treatment.