Skin cancer generally develops in the outermost layer of the skin (epidermis), so a tumour is usually clearly visible. This makes most skin cancers detectable in the early stages.

What is Skin Cancer?

Skin cancer is an abnormal growth of the skin cells.





Repeated exposure to the sun’s ultraviolet (UV) rays appears to be the most important risk factor. Other risk factors include:

• History of radiation given for treating other cancers

• Prolonged exposure to industrial chemicals

• Family history of skin cancer

• Fair or light skin complexion

• Large number of moles or atypical moles

• Weakened immune system due to drugs or diseases





Skin Cancer Types and Symptoms

The following are some of the more common malignant skin tumours.





Squamous Cell Carcinoma (SCC)













This appears as a firm irregular fleshy growth, usually on sun-exposed skin. The growth can increase in size giving rise to a large lump, which may sometimes break down to form an ulcer. If untreated, the cancer may spread to the surrounding lymph nodes. Squamous cell carcinoma usually appears in elderly patients. Chronic sun exposure is an important contributing factor in the development of this type of skin cancer. Some people who have had chronic arsenical exposure in the past may also develop these cancers later in life.





Basal Cell Carcinoma (BCC)













This is a slow-growing skin cancer. It is often painless. The cancer can look like a long-standing ulcer with a shiny or pearly raised margin. The cancer is often pigmented in Asian races. This cancer commonly appears on the face. If left untreated, it can slowly destroy the surrounding skin and underlying structures such as muscle and bone. Chronic sun exposure is also a predisposing factor in the development of basal cell carcinomas.





Malignant Melanoma













This is a cancer of the pigment cells (melanocytes) of the skin and is a dangerous type of skin cancer. It often appears as a dark brown or black skin growth or ulcer. It may look like an ordinary mole, but unlike the common mole:

• It grows more rapidly

• Its surface may have varying shades of colour

• Its surface may be thick and irregular

• Its margin may be irregular

• It may show features of change over time





Melanomas may occur spontaneously, or they may arise from a pre-existing “normal” mole. People born with large moles (giant congenital nevi) or have positive family histories of melanoma are at increased risk.





Melanoma is more common among Caucasians and less common in Asians and people with darker skin. It can occur on any site, including the palms and soles. Excessive exposure to the sun and a history of sunburns are predisposing factors.





Melanomas have a tendency to spread (metastasise) to surrounding lymph nodes or other parts of the body and can be fatal, so early detection and treatment of this condition is important.





Skin Cancer Diagnosis

Any skin lesion that is progressively growing could be a sign of skin cancer and should be examined by a doctor. Contrary to popular belief, malignant skin tumours do not always cause pain, so this symptom is not reliable.





If a skin cancer is suspected, your doctor may advise a biopsy under local anaesthetic for microscopic examination. Upon confirmation of a malignant skin tumour, the doctor can advise the best option for treatment. Alternatively, the entire lesion can be removed at the outset and sent for examination and confirmation of cancer. Rarely, a detailed evaluation may be needed to check whether the cancer has spread throughout the body.





Skin Cancer Complications

BCC may disfigure the face if it grows near the eyes, the ears or the nose. Apart from melanomas, other skin cancers are unlikely to spread to other parts of the body and are rarely fatal.





Skin Cancer Treatment

Skin cancers can be treated if detected early. All skin cancers should be destroyed or removed by surgery.

• Surgery is usually able to treat most skin cancers. Skin grafts are occasionally needed when larger tumours are removed. In certain unique cases, patients with SCC may also need surgery to remove the lymph nodes near the tumour.

• Radiotherapy may be required after surgery if cancer cells are still present or if skin cancers occur in areas that are difficult to treat with surgery. Radiotherapy is quite effective for SCC.

• Cryotherapy uses liquid nitrogen to freeze and destroy small and superficial skin cancers.

• Topical chemotherapy uses drugs in the form of a cream or liquid to be applied directly to the tumour to destroy the cancer cells. It is useful for treating some early SCCs and superficial BCCs.

• Immunotherapy uses creams to be applied directly on the affected areas to stimulate the immune system to attack the cancer cells. It is useful for treating some BCCs and SCCs.

• Photodynamic therapy uses a light-sensitive drug combined with a specific light source to destroy cancer cells. It is a newer treatment for skin cancer.





If cancer has spread to other parts of the body, chemotherapy may be used in combination with radiotherapy and surgery. Your doctor will decide on an appropriate combination of medications based on your medical history.





Skin Cancer Prevention

The risk of developing skin cancer can be reduced when sun protection measures are used consistently. Some measures to protect skin include:

• Avoiding the sun during the hottest part of the day

• Wearing long and protective clothing outdoors to protect the skin

• Wearing a wide-brimmed hat to protect your face and neck

• Using a sunscreen with a skin protection factor (SPF) of at least 15 daily

• Wearing sunglasses to protect your eyes









