We all have moles or other small lumps and bumps that are a different color to the rest of our skin. This is perfectly normal and usually nothing to worry about. It is only rarely skin cancer.
Skin cancer comes in different forms. The main types are (malignant) melanoma, basal cell cancer (BCC) and squamous cell cancer (SCC).
Basal cell cancer and squamous cell cancer are sometimes grouped together and referred to as non-melanoma skin cancer. Melanoma often looks like a very dark mole.
It is usually removed surgically. If melanoma is already at a more advanced stage, other treatments such as medication or radiation may be needed.
A typical melanoma looks like an irregularly shaped mole. It is usually dark reddish-brown or black in color, and the color is patchy. The size, shape and color can change over time.
Aside from these changes in the skin, melanoma doesn't cause any symptoms at first. People often don’t notice it, or think it's something harmless. Symptoms such as pain or bleeding generally only occur when the melanoma starts growing into the surrounding tissue or spreading to other parts of the body. So melanoma may already have reached an advanced stage by the time it is detected.
Melanoma sometimes develops inside an older mole, but it is often an entirely new skin growth.
Causes and risk factors
There are a number of different factors that can increase your likelihood of developing melanoma. These include exposure to sunlight, certain skin types, your genes and your age.
Around the world, more and more people are being diagnosed with melanomas. In Germany, about 28 out of 100,000 men and 25 out of 100,000 women developed melanomas in 2014. A total of 21,000 people were diagnosed with melanoma in 2014.
There are different types of melanoma, and each progresses in a different way. Some only grow on the surface of the skin for quite a long time and can be removed in a simple procedure. Others grow into deeper layers of skin and surrounding tissue after a shorter amount of time. They are more likely to spread through the bloodstream or lymphatic system and then form metastatic (secondary) tumors in other parts of the body. If left untreated, these kinds can be fatal within a few months.
In Germany, more than half of all melanomas are detected at an early stage. Most people with this kind of skin cancer survive it. About 11 out of 100 men and 6 out of 100 women die of melanoma within ten years of it being diagnosed.
Doctors can often tell whether an irregular-looking spot or blemish on the skin could be skin cancer just by looking at it. They can take a closer look at it using a dermatoscope. This instrument is like a strong magnifying glass with a light on it.
If the doctor thinks that someone has melanoma, it is usually removed completely – including some of the skin around the abnormal area. The removed tissue is then examined under a microscope to find out whether it really is melanoma or something else.
If it is thought that the melanoma may have already reached a more advanced stage, other examinations are carried out. For instance, nearby lymph nodes are removed and checked for cancer cells, or they are examined using ultrasound. Other imaging techniques might be used too, such as computed tomography (CT scan) or magnetic resonance imaging (MRI scan). Further laboratory tests may be needed as well.
Skin cancer screening is meant for people who don't have any symptoms. In Germany, statutory health insurers pay for skin cancer screening every two years in people aged 35 and over. The idea is to detect melanoma or other types of skin cancer before they grow deeper into the tissue or spread to other parts of the body (metastasis), with the aim of being able to provide better treatment and increase the chances of a full recovery.
In skin cancer screening, the doctor closely inspects all of your skin with their naked eye, from head to toe. For the examination to be thorough, they should also look at skin folds and mucous membranes.
You can also look out for any changes in your skin yourself, and see a doctor if you notice anything unusual.
There is no surefire way to prevent melanoma skin cancer. It is generally sensible to avoid overexposure to ultraviolet (UV) light. This mainly means not spending too much time in the sun without protection and not using tanning beds.
After melanoma is diagnosed, the first step is usually to try to remove it surgically. In advanced melanoma, the tumor has already grown into deeper layers of skin or metastatic tumors have developed elsewhere.
If surgical removal is no longer possible or not effective enough at that stage, other treatments such as radiation or medication might be used. Different medications are used for different types and stages of melanoma.
You can find information about using tanning beds on the website of the German Federal Office for Radiation Protection (Bundesamt für Strahlenschutz, or BfS).
When people are ill or need medical advice, they usually go to see their family doctor first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.
Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF), Deutsche Krebsgesellschaft (DKG), Deutsche Krebshilfe (DKH). S3-Leitlinie zur Diagnostik, Therapie und Nachsorge des Melanoms. AWMF-Registernr.: 032-024OL. July 2018. (Leitlinienprogramm Onkologie).
Bundesamt für Strahlenschutz (BfS). Optische Strahlung: Hinweise für Solariennutzer. August 03, 2018.
Dellavalle R. Skin cancer, moles, and actinic keratosis. In: Williams H, Bigby M, Herxheimer A, Naldi L, Rzany B, Dellavalle R (Ed). Edvidence-based dermatology. London: BMJ Books; 2014. S. 223-319.
Deutsche Gesellschaft für Hämatologie und Medizinische Onkologie (DGHO). Leitlinie Melanom. October 2014.
National Institute for Health and Clinical Excellence (NICE). Melanoma: assessment and management. July 2015. (NICE Guidelines; Volume 14).
Rivers JK. Is there more than one road to melanoma? Lancet 2004; 363(9410): 728-730.
Robert Koch-Institut (RKI), Gesellschaft der epidemiologischen Krebsregister in Deutschland (GEKID). Krebs in Deutschland für 2013/2014. 2017.
Walter FM, Birt L, Cavers D, Scott S, Emery J, Burrows N. 'This isn't what mine looked like': a qualitative study of symptom appraisal and help seeking in people recently diagnosed with melanoma. BMJ Open 2014; 4(7): e005566.
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