What is Skin Cancer?
Cancer is the uncontrolled turnover of cells within the body. The body has mechanisms in place to control this growth of cells but if for some reason this is disrupted then the cells get out of control leading to what is described as cancer. The disruption of this controlling mechanism can be due to a number of factors including smoking for lung cancer and the sunlight in the case of skin cancer.
Since skin cancer generally develops in the epidermis, the outermost layer of skin, a tumour is usually clearly visible. This makes most skin cancers detectable in the early stages. However before a skin cancer is detectable it may have undergone a lot of changes and the time for these changes to produce a visible change in the skin is unknown.
Types of Skin Cancer
Three types of skin cancer account for nearly 100% of all diagnosed cases. Each of these three cancers begins in a different type of cell within the skin, and each cancer is named for the type of cell in which it begins. Skin cancers are divided into one of two classes - non-melanoma skin cancers and melanoma. Melanoma is the deadliest form of skin cancer.
The different types of skin cancer are:
Basal cell carcinoma (BCC):
The most common cancer in humans, BCC develops in more than 40,000 people every year in the UK alone. About 80% of all skin cancers are BCC, a cancer that develops in the basal cells - skin cells located in the lowest layer of the epidermis. BCC can take several forms. It can appear as a shiny translucent or pearly nodule, a sore that continuously heals and then re-opens, a pink slightly elevated growth, reddish irritated patches of skin, or a waxy scar. Most BCCs appear on skin with a history of exposure to the sun, such as the face, ears, scalp, and upper trunk. These tumours tend to grow slowly and can take years to reach ½ inch in size. While these tumours very rarely metastasize (cancer spreads to other parts of the body), dermatologists encourage early diagnosis and treatment to prevent extensive damage to surrounding tissue. Because there a lot of different forms of this type of cancer there are a number of different treatments available.
Dr Cliff, the company’s lead consultant, has a particular interest in the management of BCCs which include the use of Photodynamic therapy – PDT and topical therapy.
- Photodynamic Therapy (PDT) – Involves the use of a cream applied to the skin cancer and left in place for 3 hours followed by the application of a lamp to the area for 7 minutes – this results in a transient burning sensation during which time the skin cancer is ‘killed’. This treatment may need to be repeated a week later. The advantage of the technique is that it requires no surgery so no scars - the decision as to whether this is the best treatment for you can be decided with you following a consultation.
- Topical therapy – a number of treatments are now available for patients with certain forms of BCC which involve the application of a cream to the involved area for a period of time which results in the eradication of the growth. It is not suitable for all patients - however it is effective for certain patients.
- Surgical Removal – a large number of growth need to be removed by surgery – this may involve cutting the growth out, scraping it out (curette and cautery) or burning it out (liquid nitrogen_ - they all have advantages and disadvantages and these need to be explained to you before you can make an informed decision. The purpose of the consultation is to allow you to be informed of the diagnosis and the options available. However we have been treating these cancers for many years he will make a recommendation to you however the ultimate decision is yours.
Squamous Cell Carcinoma (SCC):
About 16% of diagnosed skin cancers are SCC. This cancer begins in the squamous cells, which are found in the upper layer of the epidermis. About 200,000 cases are diagnosed ever year. SCC tends to develop in fair-skinned middle-aged and elderly people who have had long-term sun exposure. It most often appears as a crusted or scaly area of skin with a red inflamed base that resembles a growing tumour, non-healing ulcer, or crusted-over patch of skin. While most commonly found on sun-exposed areas of the body, it can develop anywhere, including the inside of the mouth and the genitalia. SCC may arise from actinic keratoses, which are dry, scaly lesions that may be skin-coloured, reddish-brown or yellowish-black. SCC requires early treatment to prevent metastasis (spreading).
These precancerous growth (actinic keratosis) and Bowen’s disease have the potential risk to progress onto skin cancer (SCC) – to prevent this from happening a number of treatments are available to limit the risk by removing these growths. These include topical therapy, phototherapy and surgical options. To limit these from coming back once treated you should adequate amount of sun block of at least SPF 15 or more applied regularly.
Accounting for about 4% of all diagnosed skin cancers, melanoma begins in the melanocytes, cells within the epidermis that give skin its colour. Melanoma has been coined “the most lethal form of skin cancer” because it can rapidly spread to the lymph system and internal organs. With early detection and proper treatment, the cure rate for melanoma is about 95%. Once its spreads, the prognosis is poor. Melanoma most often develops in a pre-existing mole or looks like a new mole, which is why it is important for people to know what their moles look like and be able to detect changes to existing moles and spot new moles.
Sun exposure is the leading cause of skin cancer. According to the American Cancer Society, “Many of the more than 1 million skin cancers diagnosed each year could be prevented with protection from the sun’s rays.” Scientists now know that exposure to the sun’s ultraviolet (UV) rays damages DNA in the skin. The body can usually repair this damage before gene mutations occur and cancer develops. When a person’s body cannot repair the damaged DNA, which can occur with cumulative sun exposure, cancer develops.
In some cases, skin cancer is an inherited condition. Between 5% and 10% of melanomas develop in people with a family history of melanoma.
Who Gets Skin Cancer?
Skin cancer develops in people of all colours, from the palest to the darkest. However, skin cancer is most likely to occur in those who have fair skin, light-coloured eyes, blonde or red hair, a tendency to burn or freckle when exposed to the sun, and a history of sun exposure. Anyone with a family history of skin cancer also has an increased risk of developing skin cancer. In dark-skinned individuals, melanoma most often develops on non-sun-exposed areas, such as the foot, underneath nails, and on the mucous membranes of the mouth, nasal passages, or genitals. Those with fair skin also can have melanoma develop in these areas.
Prevention and Early Detection Key
Sun protection can significantly decrease a person’s risk of developing skin cancer. Sun protection practices include staying out of the sun between 10am and 4pm when the rays are strongest, applying a broad-spectrum (offers UVA and UVB protection) sunscreen with a Sun Protection Factor (SPF) of 15 or higher year-round to all exposed skin, and wearing a protective clothing, such as a wide-brimmed hat and sunglasses when outdoors.