The annual skin cancer awareness month aims to raise awareness of the dangers of unprotected sun exposure. It also seeks to educate the public about ways to help prevent skin cancer.
Keep reading to know more about skin cancer and how to prevent it.
Skin cancer is an abnormal growth of skin cells — most often a malignant growth of the skin — that develop on areas exposed to the sun. This includes the scalp, face, ears, arms, hands and on the legs. It can also occur on areas of the skin not usually exposed to sunlight such as the palms, beneath your fingernails or toenails. Skin cancer affects basically every part of your body that has skin on it.
Skin cancer affects people of all colours and races, including those with darker complexions. When melanoma occurs in dark-skinned people, it is more likely to occur in areas not normally exposed to the sun. These parts include the palms of the hands and soles of the feet. Certain ethnicities are at higher risk for particular skin malignancies. Latinos, Chinese and Japanese Asians tend to develop basal cell carcinoma (BCC), the most common form of skin cancer. But the second most common, squamous cell carcinoma (SCC), is more frequent among African Americans and Asian Indians.
Skin cancers are generally not considered hereditary since they are mostly caused by ultraviolet light exposure. However, skin cancer is common among light-coloured individuals, and that skin colour is influenced by mostly the melanin pigment which is primarily determined by genetics. This fact supports the proposition that genetics to an extent does have a role to play.
Types of skin cancer
There are different types of skin cancers. The most common types are Basal cell carcinoma, Squamous cell carcinoma, and Melanoma. Other less common types of skin cancer include Kaposi sarcoma, Merkel cell carcinoma, Sebaceous gland carcinoma, Atypical fibroxanthoma, Cutaneous lymphoma, and Dermatofibrosarcoma.
1. Basal cell carcinoma (BCC)
Basal cell carcinoma is the most common skin cancer. It is likely to develop anywhere, usually in sun-exposed areas of your body such as your neck or face. There are several different variants of basal cell carcinoma. They include the superficial type, the nodular, and the morpheaform. BCCs often look like open sores, red patches, pink growths, shiny bumps, or scars. They are usually caused by a combination of cumulative and intense, occasional sun exposure.
2. Squamous cell carcinoma (SCC)
SCC is the second most common form of skin cancer. It is an uncontrolled growth of abnormal cells arising from the squamous cells in the epidermis, the skin’s outermost layer. SCCs may occur in all areas of the body, including the mucous membranes and genitals. However, they are most common in areas frequently exposed to the sun, such as the rim of the ear, lower lip, face, balding scalp, neck, hands, arms and leg.
SCC accounts for about 20% of all skin cancers, but it is more common in immunosuppressed people. People with darker skin are more likely to develop squamous cell carcinoma on areas that aren’t often exposed to the sun. SCCs often look like scaly red patches, open sores, warts or elevated growths with a central depression. They may also crust or bleed. Furthermore, they can become disfiguring and, sometimes, deadly if allowed to grow.
3. Melanoma
Melanoma is the most dangerous form of skin cancer originating from the pigment-producing skin cells (melanocytes) of the epidermis. But it is less common than the first two variants. The cancer is caused mainly by intense, occasional UV exposure from sunlight or tanning beds (frequently leading to sunburn), especially in those who are genetically predisposed to the disease.
Melanoma can develop anywhere on your body, in otherwise normal skin or in an existing mole that becomes cancerous. Melanoma most often appears on the face or the trunk of affected men. In women, this type of cancer most often develops on the lower legs. In both men and women, melanoma can occur on skin that has not been exposed to the sun. The majority of melanomas are black or brown, but they can also be skin-coloured, pink, red, purple, blue or white.
The chance of surviving melanoma is in early detection and treatment. If not, cancer can advance and spread to other parts of the body where it becomes difficult to treat and can be fatal or destructive. While it is not the most common of skin cancers, it causes the most deaths.
4. Kaposi sarcoma
This rare form of skin cancer develops in the skin’s blood vessels and causes red or purple patches on the skin or mucous membranes.
Kaposi sarcoma mainly occurs in people with weakened immune systems. This includes people with AIDS and people taking medications that suppress their natural immunity, such as those who have undergone organ transplants.
5. Merkel cell carcinoma
Merkel cell carcinoma causes firm, shiny nodules that occur on or just beneath the skin and in hair follicles. The cell carcinoma is most often found on the head, neck and trunk.
6. Sebaceous gland carcinoma
This uncommon and aggressive cancer originates in the oil glands in the skin. Sebaceous gland carcinomas — which usually appear as hard, painless nodules — can develop anywhere. However, most occur on the eyelid, where they’re frequently mistaken for other eyelid problems.
7. Atypical fibroxanthoma
Atypical fibroxanthoma (AFX) is a tumour that occurs primarily in older individuals after the skin of the head and neck has been damaged significantly by sun exposure and/or therapeutic radiation.
8. Cutaneous lymphoma
Cutaneous lymphoma is a rare subtype of non-Hodgkin lymphoma that starts in the skin. It is often not classified as a skin cancer because the cancer cells originate in white blood cells called lymphocytes. Whereas, skin cancers develop from other non-lymphoid cells.
9. Dermatofibrosarcoma protuberans
Dermatofibrosarcoma protuberans (DFSP) is a rare skin cancer. It begins in the middle layer of skin, the dermis. DFSP tends to grow slowly. It seldom spreads to other parts of the body.
Risk factors
It is not known why certain cells become cancerous. However, experts identified some risks factors for skin cancer. Most skin cancers arise from DNA mutations induced by ultraviolet light affecting cells of the epidermis. Most UV rays come from sunlight, but can also be from tanning beds. Sun exposure does not explain skin cancers that develop on skin not ordinarily exposed to sunlight. This indicates that other factors contribute to the risk of skin cancer. Many of these early cancers seem to be controlled by the natural immune system which, when compromised, may permit the development of malignant skin cells.
The most common risk factors for skin cancer are as follows.
1. Ultraviolet light exposure
Exposure to UV light either from the sun or from tanning beds can cause skin cancer regardless of skin colour. However, fair-skinned individuals, with hazel or blue eyes, and people with blond or red hair are particularly vulnerable. This is because having less melanin pigment in the skin provides less protection from the damaging UV light. The problem is worse in areas of high elevation or near the equator where sunlight exposure is more intense.
2. A weakened immune system
People with chronically suppressed immune system (immunosuppression) from underlying diseases such as HIV/AIDS infection or cancer, or from medications such as immunosuppressant drugs, have a high risk of skin cancer.
3.Exposure to radiation or certain substances
Exposure to ionising radiation (X-rays) or chemicals such as arsenic can predispose one to cancer.
4. A personal or family history of skin cancer
People who have a history of one skin cancer have a chance of developing a second skin cancer within the next two years. If one of your parents or a sibling has had skin cancer, you may have an increased risk of the disease.
5. Moles
People who have many moles or abnormal moles called dysplastic nevi have an increased risk of skin cancer. These abnormal moles look irregular and are generally larger than normal moles. They are more likely than others to become cancerous. If you have a history of abnormal moles, watch them regularly for changes.
6. Age
Elderly patients have more skin cancers.
Prevention of skin cancer
People can prevent most skin cancers by limiting or avoiding exposure to UV radiations and by avoiding triggers that cause the growth of a tumour. Prevention strategies include the following:
- Avoid the sun at the hottest hours of the day especially between the hours of 10 am to 4 pm.
- Avoid using tanning beds which are a major cause of UV light and a risk factor to skin cancer. Wear protective clothing that covers the arms and legs.
- More importantly, wear sunscreens all-round. Use a broad-spectrum sunscreen with an SPF of at least 30, even on cloudy days.
- Apply sunscreen generously, and reapply every two hours — or more often if you’re swimming or perspiring. Sunscreens do not filter out all harmful UV radiation, especially the radiation that can lead to melanoma. But they play a major role in an overall sun protection program.
- Limiting or avoiding exposure to ultraviolet (UV) radiation.
- Check your skin for suspicious changes can help detect skin cancer at its earliest stages. Early detection of the cancer gives you the greatest chance for successful skin cancer treatment.
- It is advisable to check for signs of skin cancer regularly throughout the year. Early detection improves the outlook of each type of skin cancer and can lead to better outcomes.
- Know your skin and if you have any moles or spots that are suspect, see a dermatologist for a skin cancer screening.
Awareness is key in identifying and treating skin cancers early.