Skin cancer is an uncontrolled division of cells in the skin. This results in a change on the skin, such as a rough spot that doesn’t go away, a wound that doesn’t heal or a change in color or size of an already existing skin defect. There are three types of skin cancer: basal cell carcinoma, squamous cell carcinoma and melanoma.
In most cases, skin cancer is caused by too much exposure to UV radiation, for example by excessive sunbathing. However, the sun is not the only source of UV radiation. A sunbed or sunlamp also generates UV radiation. Particularly exposure to UV radiation in childhood and frequent sunburn increase the risk of skin cancer. Skin cancer can also be hereditary. Using drugs that suppress the immune system can also increase the chance of developing skin cancer (in particular squamous cell carcinoma).
Other risk factors for skin cancer are:
- Age above fifty years.
- (Many) moles and/or freckles.
- A light complexion.
Known signs and symptoms of skin cancer are itch, bleeding, ulcers and color changes. New skin defects can emerge for no reason or existing skin defects can suddenly change.
Every type of skin cancer looks different:
- Basal cell carcinoma (BCC) is most common in the face and neck, but can also occur at other places. A basal cell carcinoma usually looks like a smooth, glassy lump. Sores and scabs may emerge on and around the lump. Basal cell carcinoma rarely spreads and grows slowly.
- Squamous cell carcinoma (SCC) is common in the face, but can also occur on the hands or back. A squamous cell carcinoma is often pale pink in color with a central white, flaky spot. It feels rough. Squamous cell carcinoma grows rapidly and can spread.
- Melanoma is the most malignant type of skin cancer. A melanoma usually develops from a mole, but this need not necessarily be the case. In women, melanoma is often located on the torso and legs. In men, on the torso, head and neck. One can recognize a melanoma as a mole thickens, changes color and/or begins to have an irregular shape. Often, such a mole itches too. In a more advanced stage, a scab or sore may emerge on the mole or it can start bleeding. Melanomas grow rapidly and may already spread in a relatively early stage to lymph nodes and other organs. If that happens, it's very difficult to treat.
The general practitioner will assess the change in the skin, may remove a small piece of tissue (biopsy), make a diagnosis and then immediately start treatment. The patient may also be referred to a specialist, such as a dermatologist or plastic surgeon. In some cases, no biopsy is taken but the doctor chooses to remove the entire tumor at once.
In case of skin cancer, there are several treatments possible:
- Surgery. The tumor is cut out of the body. The removed part is then examined in the laboratory to see if everything has actually been removed. If this is not the case, even more tissue must be removed.
- Radiation therapy. The cancer cells are destroyed by radioactive radiation. Cancer cells are less resistant against this radiation than healthy cells and thus die, while healthy cells remain alive. Radiation therapy is also used to kill metastases. Some side effects of radiation therapy are fatigue and skin discoloration around the irradiated area.
- Freezing. The tumor is frozen with liquid nitrogen, similar to the removal of warts. This treatment often leaves a scar.
- Burning (electrocoagulation). Under local anesthesia, the tumor cells are burned away using an electric current.
- Light therapy (photodynamic therapy). With a cream, the tumor cells are made sensitive to (red) light. If the spot is then illuminated with this light, the tumor cells break down. A disadvantage of this therapy is that it can hurt a lot.
- Chemotherapy. A cream is applied onto the tumor, which includes substances that will kill the tumor cells. This cream is applied with gloves or a cotton swab, because otherwise it also damages the cells at the fingers.
- Immunotherapy. This is also a cream, but it stimulates the individual’s immune system to get rid of cancer cells.
Which treatment ultimately will be chosen, depends on the type of skin cancer that a person has and how far the cancer has progressed. Sometimes, a combination of treatments is done in order to remove any metastases. After treatment, the patient often remains under control with the doctor for several years to see if the cancer doesn’t come back.
Skin cancer is the most common type of cancer that, with timely intervention, can be properly cured in most cases. Of patients with basal cell carcinoma, almost one hundred percent heals. In squamous cell carcinoma, the cure rate is over ninety percent. In melanoma, the chance of survival is high when the tumor is detected and treated early. In about eighty percent of the patients, the disease does not return within five years. In patients with metastases in the lymph node, the survival rate is lower.
When melanoma cells enter via the blood into other organs, the specialist examines whether treatment is an option. Treatment is then mainly focused on inhibiting the disease and/or reducing or preventing symptoms.
Always be careful in the sun:
- Don’t go sunbathing between 12 and 15 hours (daylight saving time). The sun is most powerful then.
- If you are frequently in the sun, wear a hat or sun visor. Also protect the skin by covering the arms and legs with clothing.
- When being in the sun, always use sunscreen with a high sun protection factor.
- In the fifth century BC, the Greek doctor Hippocrates was the first who made a description of a melanoma.
- The term ‘melanoma’ is derived from the Greek word melanoma, which is derived from melas (dark, black) and oma (tumor).
- The prevalence of skin cancer is 0.2%.