There are three main types of skin cancer: basal cell carcinoma (BBC) which is the most common one, squamous cell carcinoma (SCC) and melanoma. Patients who develop a basal cell or squamous cell carcinoma have a 30-50% chance of developing a second within 5 years. They also have an increased risk of developing melanoma. They should therefore be monitored at regular intervals.
- Basal cell carcinoma is quite common in people over 60 years of age and usually occurs in body areas that have been extensively exposed to the sun- especially on the face, ears, neck, head, shoulders and back. Sun damage (photoageing, actinic keratoses), repeated prior episodes of sunburn, fair skin patients with blue eyes and blond or red hair, contact with arsenic, ionising radiation, chronic skin conditions, burns, scars, and vaccines are risk factors. BCC is a locally invasive skin tumour and it rarely gives metastases. Sometimes basal cell carcinomas can resemble non-cancerous skin lesions, such as psoriasis or eczema. The diagnosis is made clinically with the help of dermoscopy, and confirmed by biopsy. It is treated by surgical removal.
- Squamous cell carcinoma is the second most common skin cancer and is usually found in more sun affected areas, such as the face, ears, lips and scalp. It presents as enlarging scaly or crusted lump, slightly sore and easily bleeding. Its size varies from a few millimetres to several centimetres in diameter. It grow over weeks to months and may ulcerate. SCC may occur de novo or within pre-existing pre-cancerous lesions such as actinic keratosis or Bowen’s disease. It is treated by surgical removal.
- Melanoma can rise from otherwise normal-appearing skin or from within a mole or freckle,. When there is a mark (a mole) that is brown or black, it should be periodically checked and observed for any change. If the lesion grows sharply, if the color darkens, bleeds, causes pain and generally if there is any change, we should seek the advice of a Dermatologist. Since melanoma can give metastases, early diagnosis is essential. It is the biopsy that will make the definitive diagnosis. All patients should be treated surgically. Melanoma and surrounding healthy skin should be excised.
The types of melanoma are as follows:
- Superficial Spreading Melanoma. Superficial melanoma is responsible for 70% of melanoma cases and occurs at any age. It appears as a small lesion with irregular borders. The color of the lesion can be red, white, blue or black-blue. It can occur anywhere on the body, but most commonly it occurs on the trunk or palms and hands.
- Nodular Melanoma. Nodular melanoma is the most aggressive type of melanoma. It appears as a firm, dense tumor anywhere on the skin. They are usually black, but can be blue, gray, white, brown, dusky, red or skin color. It can be ulcerated and not fully healed. Nodular melanomas account for 10-15% of melanoma cases. It occurs more often at the age of 50-60 and affects twice as many men than women. It usually occurs in the head, neck and chest.
- Acral Lentiginous Melanoma. This melanoma appears as dark lesions (spots or freckles) on the palms, toes, feet and mucous membranes. It accounts for 10% of melanoma cases.
- Lentigo maligna melanoma. It appears as a large brown spot with irregular shape and variable pigmentation located on the face or neck, particularly the nose and cheek. It accounts for about 5% of melanoma cases. It often affects the elderly and is associated with skin aging. A non-cancerous (benign) brown spot may appear many years before it becomes cancerous.
- Amelanotic Melanoma. Any subtype of melanoma can be amelanotic. Its characteristic feature is that it is has no pigment.