Skin Cancer

what causes skin cancer?

Skin cancer happens when normal cells in the skin change into abnormal cells. The cause is complex and involves multiple factors including ultraviolet light exposure (sunlight, tanning beds), genetics and changes in genes (DNA) that control cell growth.

There are 2 main types of skin cancer :

• melanoma
• non-melanoma – “basal cell carcinoma” and “squamous cell carcinoma.”

Chronic sun exposure and sunburn are major contributing factors to skin cancer . The damaging effects of the sun build up over time. The more you are exposed to the sun (or to tanning beds) in your life, the higher your risk of skin cancer.

Non-melanoma skin cancer can occur anywhere on the skin, but is often found on the head, face, neck, back of the hands, arms, and legs. This is because those body parts are most exposed to the sun’s rays.

Most forms of non-melanoma skin cancer can be easily treated because they grow slowly. But if not treated, some non-melanoma skin cancers can become large or spread inside the body.

Basal Cell Carcinoma (BCC)

This is the most common cancer affecting human beings. It is a slow growing skin cancer. It is often painless. The majority of lesions appear on sun exposed skin .The cancer can present as a longstanding ulcer with a shiny or pink-  pearly raised  papules.. Sometimes, they may have a firm, scar like appearance with no symptoms. BCC rarely spreads to internal organs, but can be dangerous in that they can destroy important structures such as the eyelid, nose or lips.

Therapy includes surgical excision,PDT radiation therapy and in selected cases, use of creams that stimulate the immune system to destroy or shrink the tumor. The cure rate is over 95% if diagnosed and treated at an early stage.

Squamous Cell Carcinoma (SCC)

SCC usually appears in elderly patients due to cumulative chronic sun exposure It  favors sun exposed skin as well as skin that may have received radiation therapy or skin near a chronic wound such as an  ulcer. . They appear as growths that may be pink or flat or bumps with some red or pink color. They often have a rough, scaling, “dry” appearing surface and may be tender to the touch. Advanced SCC has the potential of spreading to internal tissues such as lymph nodes .This is why early diagnosis and treatment is crucial.

Therapy includes surgical excision, radiation therapy and injection of medication into the SCC. The cure rate for early SCC is very high but declines for more advanced tumors.

Malignant Melanoma

This is a cancer of the pigment cells (melanocytes) of the skin, and is a very dangerous  type of skin cancer. It often presents as a dark brown or black skin growth or ulcer.  It may look like an ordinary mole.  Unlike the common mole however, it grows more rapidly; its surface may have varying shades of colour; its surface may be thick and irregular; its margin may be irregular; and it may show features of change over time.

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

Melanoma is more common among Caucasians . 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 (metastasize) to surrounding lymph nodes or other parts of the body, leading to morbidity and mortality. Early detection and treatment of this condition is therefore  important.

Diagnosis of skin cancers

Any skin lesion that is progressively enlarging should be examined by a trained doctor.

If you notice any of these warning signs, see a doctor or dermatologist immediately: 

If a skin cancer is suspected, your doctor may advise a biopsy to be done under local anesthetic. Upon confirmation of a skin cancer, the doctor can assess and advise on the best option for treatment. The right treatment for you will depend  on the type of skin cancer you have, its size and location, as well as your  age and other health problems.

Treatment

The most common form of treatment of a malignant skin tumour is excision,  which involves removing the entire skin lesion. In certain situations whereby complete excision may not be feasible, other forms of therapy such as radiotherapy, photodynamic therapy or topical therapy may be used. If the cancer has spread to involve the lymph nodes or other organs then the patient may need to be managed jointly with an oncologist and/or surgeon.

Follow up

After removal of a  skin cancer,  patients will need to be followed up regularly by the doctor for a few years. This is to look out for any recurrences of the skin cancer  that may occur. It also gives the doctor a chance to assess whether new skin cancers have developed in other areas.