Stage 4 melanoma doesn’t have one single appearance. By definition, it means melanoma has spread beyond the original skin site to distant parts of the body, so what you see and feel depends on where those metastases land. The original mole or lesion may still be visible on the skin, but the defining feature of stage 4 is what’s happening beneath the surface: cancer in the lungs, liver, brain, bones, or distant skin and soft tissue.
What the Original Skin Lesion Looks Like
The primary melanoma, the spot where the cancer started, often follows the familiar ABCDE warning signs: asymmetry, irregular borders, multiple colors, a diameter larger than a pencil eraser, and evolution in size or shape over time. But by the time melanoma reaches stage 4, the original lesion may have been surgically removed months or years earlier. In some cases it’s still present and may appear ulcerated, meaning the skin over the tumor has broken down, leaving a raw or crusted surface that can bleed.
About 15% of melanomas are the nodular type, which is particularly aggressive. Nodular melanoma often looks like a raised dome-shaped bump rather than a flat, spreading mole. It’s typically dark brown to black, and can resemble a blood blister or blood vessel growth. Roughly 5% of nodular melanomas have no pigment at all, appearing pink or skin-colored, which makes them easy to miss or mistake for a benign bump.
Skin Metastases You Can See and Feel
One of the visible hallmarks of advanced melanoma is the appearance of new lumps on or under the skin, sometimes far from the original site. These are distant skin metastases, small, firm, rounded nodules that sit in the fat layer just beneath the skin. On imaging, they appear as discrete rounded densities in the subcutaneous fat, and they can be subtle because of their small size and location near the body’s surface.
You might notice these as painless lumps that are dark, bluish, or sometimes skin-colored. They can show up anywhere on the body. Satellite lesions (small tumors that develop very close to the primary site) and in-transit metastases (tumors that appear between the original melanoma and the nearest lymph nodes) are classified as stage 3, not stage 4. Stage 4 specifically means the cancer has traveled to distant organs or distant areas of skin well beyond the regional lymph nodes.
How Stage 4 Is Classified
Doctors categorize stage 4 melanoma based on where it has spread. The current staging system breaks it into subcategories:
- M1a: spread to distant skin, soft tissue, or distant lymph nodes
- M1b: spread to the lungs
- M1c: spread to organs other than the lungs or brain (liver, bone, gut)
- M1d: spread to the brain or central nervous system, with or without disease in other sites
Each subcategory also factors in a blood marker called LDH. When this enzyme is elevated, it generally signals a higher tumor burden and a less favorable outlook, regardless of where the metastases are located.
What Lung Metastases Feel Like
The lungs are one of the most common places melanoma spreads. You won’t see anything on the skin, but the symptoms can include persistent breathlessness, a cough that doesn’t go away, or coughing up blood. Many small lung metastases cause no symptoms at all and are only discovered on CT or PET scans during routine staging. PET/CT scans are particularly effective at detecting distant spread when the original melanoma was thicker than about 2.85 millimeters.
Symptoms of Brain Metastases
Brain involvement, now given its own staging designation (M1d) because of its distinct impact on prognosis, can cause headaches and nausea that tend to be worse first thing in the morning. Depending on which part of the brain is affected, you might also experience numbness or weakness in an arm or leg, difficulty with balance, changes in vision, personality shifts, or seizures. These symptoms can develop gradually or appear suddenly.
Signs of Liver and Bone Spread
When melanoma reaches the liver, you may feel discomfort or a dull ache under the ribs on the right side of your abdomen. Nausea is common. In some cases, the liver becomes enlarged enough that a doctor can feel it during a physical exam, though this is often detected earlier on imaging.
Bone metastases cause deep, persistent bone pain that doesn’t improve with rest. If the cancer spreads to the spine, it can compress the spinal cord, a serious complication that produces back or neck pain (sometimes described as a band-like sensation around the chest or abdomen), weakness or numbness in the legs, and in severe cases, loss of bladder or bowel control. Spinal cord compression requires urgent treatment.
How Survival Has Changed
Stage 4 melanoma carries the most serious prognosis of any melanoma stage. About 5% of melanoma cases are diagnosed after the cancer has already spread to distant sites. According to SEER data from 2016 to 2022, the five-year relative survival rate for distant-stage melanoma is 34%. That number reflects a significant improvement over earlier decades, driven largely by immunotherapy and targeted therapy drugs that became standard treatments in the 2010s. Before those options existed, the five-year survival rate was in the single digits.
Prognosis varies widely within stage 4. Someone with a single small metastasis in distant skin has a different outlook than someone with widespread brain involvement and elevated LDH. Treatment response also matters enormously: a subset of patients on newer immunotherapies achieve durable remissions lasting years.
What to Actually Look For
If you’re examining your own skin, the most concerning changes are new lumps or nodules that appear firm and grow steadily, especially if you have a history of melanoma. A mole that changes shape, color, or size, or one that begins to bleed or ulcerate, warrants prompt evaluation. Keep in mind that some melanomas lack pigment entirely, so a persistent pink or flesh-colored bump that doesn’t heal can be just as significant as a dark one.
For people already diagnosed with melanoma, new or unexplained symptoms like persistent cough, unexplained headaches, bone pain, or abdominal discomfort should be reported to your care team. Stage 4 melanoma is often detected on surveillance imaging before symptoms appear, which is one reason regular follow-up scans are part of the long-term monitoring plan after a melanoma diagnosis.