There are three main types of skin cancer. All skin cancers can grow and spread, however some are less harmful than others.
- Basal cell carcinoma (non-melanoma)
- Squamous cell carcinoma (non-melanoma)
- Melanoma - the most dangerous form of skin cancer
Not all sun damaged cells become cancerous. Chronic sun damage can result in sun spots, a condition known as Actinic Keratoses (or Solar Keratoses). Sun spots are different to moles, freckles and age spots, as it is a condition that affects an area of skin rather than an individual spot. Sun spots can develop over a long period of time and may not be visible on the skin until many years later.
Anyone can develop sun spots. It is important to have these checked when noticed, because they may later develop into a skin cancer. Actinic Keratoses is usually treated with cryotherapy or topical therapy.
Basal Cell Carcinoma (BCC)
This is the most common and least dangerous form of skin cancer. BCCs account for about two thirds of all skin cancers and may have the following features:
- A slow growth rate, usually doubling in size over a period of twelve months
- Commonly occur on on the head, neck and upper torso
- May appear as a lump
- May appear as a red, patchy area that can be mistaken for psoriasis, eczema or tinea
- May appear pale or pearly in colour, as a poorly defined scar in sun damaged area
- May ulcerate as it grows, bleed when irritated or appear as a recurring sore that fails to heal
There are various treatment options, depending on the type of BCC you have been diagnosed with. For instance, some very small and superficial BCCs can be treated using a topical cream or gel. Larger BCCs embedded in skin, usually require surgical excision.
Squamous Cell Carcinoma (SCC)
SCCs are less common than BCC, accounting for about 30% of skin cancers. However, they are more dangerous than BCCs because they can grow rapidly and spread to other parts of the body if untreated. SCCs are more common on areas of skin most often exposed to the sun and may have the following features:
- May appear to be slowly expanding over the skin, but can also grow very rapidly
- Commonly occur on the hands, forearms, ears, lips, scalp, forehead and shins
- May be tender to touch or painful
- May appear as a red patch that can be mistaken for psoriasis or eczema
- May appear thick, crusty and keratinised
- May bleed easily and ulcerate.
There are various treatment options, depending on the type of SCC you have been diagnosed with. For instance, some very small and superficial SCCs can be treated using a topical cream or gel. More severe SCCs usually require surgical excision.
Melanoma accounts for about 3% of skin cancer and is the most dangerous by far. Melanoma can be life-threatening in as little as six weeks if left untreated, as it can spread to other parts of the body. Melanoma can be difficult to diagnose, because it is one of the smallest type of all cancers. It can also appear on skin not typically exposed to the sun, such as the inner thigh, underarm, between the toes, on the soles of feet and palms of hands, under the nails, and even internally. The Current Clinical Guidelines indicate that those with the highest risk of developing melanoma include people who:
- Have a fair complexion, with a tendency to burn rather than tan
- Have a family history of melanoma
- Had a high incidence of childhood sunburn
- Have a past history of BCCs or SCCs
- Are 30 years old or more, (over 50 years most at risk)
- Have a presence of ‘sun spots’ or ‘age spots:’ dark patches of skin caused by sun damage, otherwise known as solar lentigines
- Have numerous moles: multiple atypical or dysplastic naevi, otherwise known as dysplastic naves syndrome
The guidelines for diagnosis melanoma follow the ABCD rule. Your practitioner will be looking for any lesions that are asymmetrical, have irregular borders, uneven colour, and a diameter of 6mm or more. Melanoma will always need to be removed by surgical excision. Any skin cancer that is clearly excised has a 96% rate of cure. If a melanoma is not excised in a short time frame, or occur on areas of the body, such as the eye, nose and lips, they can become more aggressive and metastatic. This means that it will spread to other parts of the body. This is the type of skin cancer that can become fatal. If a melanoma metastasises, radiation therapy will be required.
All types of melanoma require surgical excision.