Skin cancer is a malignant growth on the skin, which can have many causes. Skin cancer generally develops in the epidermis (the outermost layer of skin), so a tumor is usually clearly visible. It is the most common form of human cancer. It develops primarily on areas of sun-exposed skin, including the scalp, face, lips, ears, neck, chest, arms and hands, and on the legs in women.
The most common warning sign of skin cancer is a change in the appearance of the skin, such as a new growth or a sore that will not heal.
The top layer of skin (the epidermis) provides a protective layer of skin cells that your body continually sheds. The epidermis contains three types of cells: a)Squamous cells that lie just below the outer surface, b) Basal cells which produce new skin cells and sit beneath the squamous cells, c) Melanocytes, which produce the pigment that gives skin its normal colour (melanin) and are located in the lower part of the epidermis.
People with certain risk factors are more likely to develop skin cancer. These risk factors can be listed as below:
- Lighter natural skin colour
- Family history of skin cancer
- Personal history of skin cancer
- Exposure to the sun
- A history of sunburns early in life
- Skin that burns, freckles, reddens easily, or becomes painful in the sun
- Blue or green eyes
- Blond or red hair
- Certain types and a large number of moles
The best known cause of skin cancer development is the ultraviolet (UV) radiation found in sunlight, commercial tanning lamps and tanning beds. Both ultraviolet A and ultraviolet B contribute to skin cancer. The best way to prevent skin cancer is the protection from the sun. The five easy options for sun protection:
- Seek shade, especially during midday hours (10:00 a.m.-4:00 p.m.), when UV rays are strongest and do the most damage.
- Cover up with clothing to protect exposed skin.
- Get a hat with a wide brim to shade the face, head, ears, and neck.
- Grab shades that wrap around and block as close to 100% of both UVA and UVB rays as possible.
- Rub on sunscreen with sun protective factor (SPF) 15 or higher, and both UVA and UVB protection.
The most common warning sign of skin cancer is a change on the skin, especially a new growth or a sore that doesn’t heal. The cancer may start as a small, smooth, shiny, pale, or waxy lump. Or it can appear as a firm red lump. Sometimes, the lump bleeds or develops a crust. Skin cancer can also start as a flat, red spot that is rough, dry, or scaly. Actinic keratosis, which appears as rough, red or brown scaly patches on the skin can sometimes turn into a squamous cell cancer. Like skin cancer, it usually appears on sun-exposed areas but can be found elsewhere.
Changes in the skin are not sure signs of cancer; however, it is important to see a doctor if any symptom lasts longer than 2 weeks. There are mainly three different forms of skin cancer.
- Basal cell carcinoma: This form makes up approximately 70-75 % of all. It is usually locally destructive and progress very slowly.
- Squamous cell carcinoma: While making about 25 % of all skin cancers, it can be more aggressive and rarely spread to local lymph nodes.
- Malignant melanoma: 1-5 %. It is a very aggressive tumours and very frequently seen with regional and/or distant metastasis.
When an area of skin does not look normal, the doctor check it thoroughly using dermatoscopy looking for signs of malignancy and may remove all or part of the growth, which is called a biopsy. This tissue is sent for a histopathologic examination to check for cancer cells. A biopsy is the only sure way to tell if the problem is cancer.
The skin cancer is usually a local disease and very rarely spreads beyond the skin, except for malignant melanoma. Only in very large and long lasting cancer may need regional and distant metastasis to decide on the stage of the disease.
In treating skin cancer, the main goal is to remove or destroy the cancer completely with as small a scar as possible. Best treatment option for everybody can change according to the location and size of the cancer, the risk of scarring, and the person’s age, general health, and medical history. Curettage and Electrodesiccation, cryotherapy, laser, topical medication and surgery are different treatment options for skin cancer. Choosing the right option depends on the severity and type of skin cancer.
For all cancers, a serious follow up on a regular basis is necessary for at least 3-5 years.