Melanoma

Melanoma is a skin cancer that can spread to other parts of the body. Most cases are found early. Early disease is highly treatable.¹ This guide explains the types and stages. It can help you see where a diagnosis fits and what care may follow.

Key points

• The cancer may sit in the top skin layer, grow deeper, or spread. These stages need different care.
• Most early cases are cured with surgery. Disease that has spread may need drugs from a cancer team.²
• Stage helps predict the outlook. A new or changing mole is a warning sign.

What is melanoma?

Melanoma starts in the cells that give skin its color, called melanocytes. It may start in a mole or as a new spot. It can grow anywhere, even on the soles, palms, or under a nail. Sunlight and tanning beds raise the risk. So do many moles, fair skin, and a family history. It can spread, so a changing spot needs a check.

The melanoma family: where a diagnosis fits

The team checks how deep it has grown and whether it has spread. These findings set the stage:

• Melanoma in situ (Stage 0). Cancer cells sit only in the top skin layer. They cannot spread while they remain truly in situ. Surgery to clear the edges usually cures it. The melanoma in situ guide covers this. One type on skin with years of sun damage is lentigo maligna (see the lentigo maligna guide).
• Stage I–II. The cancer has grown deeper into the skin but has not spread to other sites. Depth and a break in the surface help set its stage. Surgery is the main treatment. Some high-risk cases also need drugs.
• Stage III–IV melanoma. Stage III means spread to nearby lymph nodes or nearby skin or lymph channels. Stage IV means spread to distant sites. Surgery may still play a role. Drug treatment depends on the stage and whether the cancer can be removed.³

There are also subtypes. Superficial spreading is the most common. Nodular types can grow down fast. Lentigo maligna melanoma is the invasive form that grows from lentigo maligna. Acral types grow on palms, soles, or under nails. Stage guides much of the treatment, but type and site also matter.

Warning signs: the ABCDEs

A new or changing mole is the most important clue. The ABCDE guide helps spot a worrisome mole:

• Asymmetry: one half does not match the other
• Border: edges are ragged, notched, or blurred
• Color: more than one color, or uneven color
• Diameter: larger than a pencil eraser (about 6 mm), though melanomas can be smaller
• Evolving: changing in size, shape, color, or feel, or a new spot

Another simple clue is the "ugly duckling": a mole that looks different from your others. Anything new, changing, bleeding, or itchy is worth getting checked.

How it is diagnosed and staged

The clinician checks the spot, often with a lighted lens. A suspicious spot needs a biopsy. The aim is to remove the whole spot with a small margin when practical. A large spot or one in a hard-to-reach site may need a sample of just part.²

If cancer is found, the report gives its Breslow thickness. This is its depth in millimeters. Thin tumors tend to have a better outlook. Thickness and a break in the surface (ulceration) help set the stage. The team also checks whether it has spread to lymph nodes, nearby skin, or distant sites. Stage guides treatment.⁴

Treatment, by stage

Treatment follows the stage. Here is the short version of each; the deeper guides cover the details.

Melanoma in situ

Stage 0 cancer is removed with a margin of skin. Clear edges usually mean a cure. For lentigo maligna, a specialist may offer a cream or radiation if surgery is not suitable or is declined. These need close checks. Proof of lasting cure is less certain than for surgery. The melanoma in situ guide covers this in full.

Invasive melanoma

For cancer that has grown deeper, surgery is the main treatment. The surgeon removes a margin of normal skin. Its width depends on the depth of the tumor.⁵⁶

Some people need care beyond surgery. An oncology team may offer drug treatment after surgery for high-risk stage II disease, even when no lymph nodes are involved. For stage III–IV disease, the team chooses care based on where the cancer is and whether it can be removed.³ Other options in selected settings include:

• Radiation can be added after surgery in certain higher-risk situations, used when surgery is not a good option, or given to ease symptoms.²
• Neoadjuvant immunotherapy means immunotherapy given before surgery, for higher-risk melanoma that can still be removed. It is used in selected patients.⁷
• Intralesional or limb-directed therapy uses an injection into the tumor, or treatment delivered to an affected arm or leg. These approaches may be used for cancer in nearby skin or lymph channels ("in-transit" disease). The options depend on whether it can be removed.⁸³

Checking the lymph nodes

For thicker melanomas, a sentinel lymph node biopsy may be offered. This checks the first lymph node the melanoma would drain to. It is mainly a staging tool. The result helps predict outlook and decide whether to discuss more treatment.⁹ The trial did not show a clear survival gain for the whole group. If that node has melanoma, doctors now often watch the area with ultrasound rather than removing all the nodes, because removing them did not improve survival in a large trial.¹⁰

Advanced melanoma

For stage III–IV melanoma, the plan may include surgery, drug treatment, or both. An oncology team coordinates the drugs:

• Immunotherapy helps the immune system attack the melanoma. After surgery for higher-risk disease it lowers the chance of return, and for spread melanoma it has meaningfully improved long-term survival.¹¹¹²
• Targeted pills (BRAF/MEK inhibitors) are an option for the roughly half of melanomas that carry a BRAF gene change, found by gene testing.¹³

This care is coordinated by referral to a medical oncologist.

Other options patients ask about

Black salve or Cansema. Do not use these to remove a mole or melanoma. They can kill healthy skin while leaving cancer behind. A scab or a flat scar does not prove a cure. Tissue studies show harm and cancer that remained after use.¹⁴¹⁵

Home mole removal. Do not cut, burn, freeze, or use acids on a mole. Even vinegar has caused burns when used this way. A biopsy lets the team find out if a spot is melanoma and measure its depth. Home removal can damage the tissue needed for that test.¹⁶²

Natural cures, diets, herbs, or supplements. None has been shown to cure melanoma. Some products interact with cancer drugs. Tell your care team what you use. Support for pain, stress, or nutrition can help during treatment, but should not replace care that treats the cancer.¹⁷

Creams instead of surgery. An off-label cream is sometimes used for lentigo maligna when surgery is not suitable. This does not make it a treatment for invasive melanoma. No home cream can show how deep a melanoma is. Ask which type you have before weighing treatment choices.²

Waiting or declining care. Melanoma can spread, so do not wait for a changing spot to hurt. Arrange a prompt check. If treatment feels too hard because of other illness, cost, or fear, tell the team. A plan can weigh treatment, symptom relief, and your goals. Leaving a suspected melanoma unchecked is not a safe substitute for that discussion.³

Lowering your risk and catching it early

Sunlight and tanning beds raise risk. Use shade, protective clothes, and sunscreen. One trial follow-up found fewer melanomas with daily sunscreen, but the overall result was uncertain. The result was clearer for invasive disease. It was not clear for in situ disease.¹⁸ Know your skin. Have a new or changing spot checked.