Is melanoma fast or slow growing?
Sarah Smith
Published Jan 15, 2026
Melanoma can grow very quickly. It can become life-threatening in as little as 6 weeks and, if untreated, it can spread to other parts of the body. Melanoma can appear on skin not normally exposed to the sun. Nodular melanoma is a highly dangerous form of melanoma that looks different from common melanomas.
Can melanoma be slow growing?
Lentigo maligna melanoma
It might slowly get bigger over several years and might change shape or colour. If it becomes a lentigo maligna melanoma, it starts to grow down into the deeper layers of the skin and may form lumps (nodules). Between 5 and 15 out of every 100 melanomas (5 to 15%) are this type.
What does fast growing melanoma look like?
According to Australian researchers, rapidly growing melanomas are thicker, symmetrical, or elevated, have regular borders, and often itch or bleed. They do not fit the ABCD rule for melanoma, which stands for asymmetry, border irregularity, color irregularity, large diameter, the team notes.
How can you tell if a spot is melanoma?
Spread of pigment from the border of a spot into surrounding skin. Redness or a new swelling beyond the border of the mole. Change in sensation, such as itchiness, tenderness, or pain. Change in the surface of a mole – scaliness, oozing, bleeding, or the appearance of a lump or bump.
What does Stage 1 melanoma look like?
Stage IA Melanoma: The melanoma tumor is less than 1.0 millimeter thick (less than the size of a sharpened pencil point) with or without ulceration (broken skin) when viewed under the microscope. Stage IB Melanoma: The melanoma tumor is more than 1.0 millimeter and less than 2.0 millimeters thick without ulceration.
27 related questions foundAre fast growing moles cancerous?
They can be anywhere on your body, alone or in groups. Almost all moles are benign (noncancerous). But new moles in an adult are more likely to become cancerous than old moles. If a new mole appears when you're older, or if a mole changes in appearance, you should see a dermatologist to make sure it's not cancerous.
How fast does lentigo maligna melanoma grow?
It grows slowly in diameter over 5 to 20 years or longer. Lentigo maligna melanoma is diagnosed when the melanoma cells have invaded into the dermis and deeper layers of skin. Lentigo maligna has a lower rate of transformation to invasive melanoma than the other forms of melanoma in situ (under 5% overall).
Does melanoma spread fast?
How fast does melanoma spread and grow to local lymph nodes and other organs? “Melanoma can grow extremely quickly and can become life-threatening in as little as six weeks,” noted Dr. Duncanson. “If left untreated, melanoma begins to spread, advancing its stage and worsening the prognosis.”
How long can you live with melanoma without knowing?
How long can you have melanoma and not know it? It depends on the type of melanoma. For example, nodular melanoma grows rapidly over a matter of weeks, while a radial melanoma can slowly spread over the span of a decade. Like a cavity, a melanoma may grow for years before producing any significant symptoms.
How long can melanoma go untreated?
Melanoma is less common than basal and squamous cell carcinoma, but it is far more dangerous. The biggest reason for this is its ability to spread rapidly to other organs if not treated early. Melanoma can put a patient's life at risk in as little as six weeks if left to grow untreated.
Can a melanoma appear overnight?
Melanomas may appear suddenly and without warning. They are found most frequently on the face and neck, upper back and legs, but can occur anywhere on the body.
How often does lentigo maligna turn into melanoma?
The percentage of lentigo maligna that progress to lentigo maligna melanoma remains unknown, but estimates of the lifetime risk of developing lentigo maligna melanoma in patients diagnosed with lentigo maligna at age 45 years appears to be 5%.
What does Stage 1 melanoma mean?
Stage I Melanoma
This is a noninvasive stage, which is also called melanoma “in situ,” meaning “in its original place.” With stage I melanoma, the tumor's thickness is 1mm or less. This tumor may or may not have ulcerated, and it isn't yet believed to have spread beyond the original site.
What is the stage before melanoma?
Doctors also use a cancer's stage when talking about survival statistics. The earliest stage melanomas are stage 0 (melanoma in situ), and then range from stages I (1) through IV (4). Some stages are split further, using capital letters (A, B, etc.). As a rule, the lower the number, the less the cancer has spread.
Can a fast growing mole be benign?
Congenital mole
Congenital moles, or birthmarks, are present at birth. Congenital moles can vary drastically in size with some being quite large. While these moles are usually benign, having a congenital mole, especially one that is very large, can slightly increase a person's risk of developing melanoma.
Does melanoma always grow in size?
Color that is uneven: Shades of black, brown, and tan may be present. Areas of white, gray, red, pink, or blue may also be seen. Diameter: There is a change in size, usually an increase. Melanomas can be tiny, but most are larger than the size of a pea (larger than 6 millimeters or about 1/4 inch).
Is a melanoma raised or flat?
The most common type of melanoma usually appears as a flat or barely raised lesion with irregular edges and different colours. Fifty per cent of these melanomas occur in preexisting moles.
What can be mistaken for melanoma?
Top 5 Conditions Often Mistaken For Skin Cancer
- Psoriasis. Psoriasis is a skin condition that is believed to be related to an immune system problem, which causes T cells to attack healthy skin cells by accident. ...
- Seborrheic Keratoses (Benign tumour) ...
- Sebaceous hyperplasia. ...
- Nevus (mole) ...
- Cherry angioma.
Are cancerous moles hard or soft?
A mole that is asymmetric and/or has uneven edges can be a sign of melanoma. It may feel bumpy and/or rough to the touch – or you may feel a hard lump.
Is there a difference between melanoma and malignant melanoma?
Melanoma is a cancer that begins in the melanocytes. Other names for this cancer include malignant melanoma and cutaneous melanoma. Most melanoma cells still make melanin, so melanoma tumors are usually brown or black. But some melanomas do not make melanin and can appear pink, tan, or even white.
What is the difference between lentigo and lentigo maligna?
Lentigo maligna presents as a slowly growing or changing patch of discoloured skin. At first, it often resembles a freckle or benign lentigo. It becomes more distinctive and atypical in time, often growing to several centimetres over several years or even decades.
Should lentigo maligna be removed?
As Lentigo Maligna is a pre-cancerous condition, which can be cured by surgery, no medical follow up is necessary. However, although these pre- cancerous cells are unlikely to come back, there is a small risk they can return and therefore, we will advise you to check your operation site monthly for any skin changes.
Is lentigo maligna melanoma cancerous?
Lentigo maligna (LM) and lentigo maligna melanoma (LMM) are types of skin cancer. They begin when the melanocytes in the skin grow out of control and form tumors. Melanocytes are the cells responsible for making melanin, the pigment that determines the color of the skin.
How can you tell if a spot is cancerous?
The edges are irregular, ragged, notched, or blurred. The color is not the same all over and may include shades of brown or black, sometimes with patches of pink, red, white, or blue. The spot is larger than ¼ inch across – about the size of a pencil eraser – although melanomas can sometimes be smaller than this.
Is a melanoma itchy?
While skin cancers are often asymptomatic, meaning they don't show symptoms, they can be itchy. For instance, basal cell skin cancer can appear as a raised reddish patch that itches, and melanoma can take the form of itchy dark spots or moles.