What is a basal cell carcinoma?
A basal cell carcinoma (BCC) is the commonest type of skin cancer. Although it is classified as a ‘cancer’, it almost never spread to other distant parts of the body as some cancers can do, but left untreated it will grow larger and can damage important structures, especially an area close to the eye.
What causes basal cell carcinomas?
The commonest cause of a basal cell carcinoma is too much exposure to ultraviolet (UV) light from the sun. Basal cell carcinomas can occur anywhere on your body, but are most common on areas that are exposed to the sun such as your face, head, neck and ears.
Basal cell carcinomas mainly affect fair skinned adults and are more common in men than women. Those with the highest risk of developing a basal cell carcinoma are:
- People with freckles or with pale skin and blond or red hair.
- Those who have had a lot of exposure to the sun, such as people with outdoor hobbies or who work outdoors and people who have lived in sunny climates.
- People who use sun beds.
- People who have previously had a basal cell carcinoma.
Are basal cell carcinomas hereditary?
Apart from a rare familial condition called Gorlin’s syndrome, basal cell carcinomas are not hereditary. However some of the things that increase the risk of getting one (eg a fair skin, a tendency to burn rather than tan and freckles) do run in families.
What are the symptoms of basal cell carcinomas?
Most basal cell carcinomas are painless. People often first become aware of them as a scab that bleeds occasionally and does not heal completely. Some basal cell carcinomas are very superficial and look like a scaly red flat mark. Others have a pearl-like rim surrounding a central crater. If left for years, the latter type can eventually erode the skin causing an ulcer. Other basal cell carcinomas are quite lumpy, with one or more shiny nodules crossed by small but easily seen blood vessels.
How will my basal cell carcinoma be diagnosed?
Sometimes the diagnosis is clear from its appearance. If further investigation is necessary, a small area of the abnormal skin (a biopsy) may be cut out and examined under the microscope. You will be given a local anaesthetic beforehand to numb the skin.
Can basal cell carcinomas be cured?
Basal cell carcinomas can be cured in almost every case, although treatment becomes complicated if they have been neglected for a very long time, or if they are in a sensitive place, such as near the eye.
How can a basal cell carcinoma be treated?
The commonest treatment for basal cell carcinoma is surgery, especially when the basal cell carcinoma occurs in an area like the eyelids. Usually, this means cutting away the basal cell carcinoma, along with some clear skin around it, using local anaesthetic to numb the skin. Surgery time varies from 30 minutes up to 2 hours. Most patients can have surgery as a day procedure. The removed basal cell carcinoma is then sent to the pathology laboratory to be checked to make sure it has all been removed, and the results from this come back after 24 – 48 hours. The results are provided to the patient at their follow-up appointment.
Alternatively, the basal cell carcinoma can be examined by a Pathologist at the time of removal, when it can be frozen, sliced up and examined under a microscope to give an answer within 30 – 45 minutes. This is called ‘frozen section’ and if the basal cell carcinoma is not completely removed, then more is removed to eliminate any left-over basal cell carcinoma during the same trip to hospital. This reduces the chances of having to go back to the hospital for a second operation if the basal cell carcinoma is not completely removed, and also reduces the chances of the basal cell carcinoma growing back in the future.
Another type of surgery to remove a basal cell carcinoma is called Mohs’ micrographic surgery. This involves the removal of the affected skin that is then thoroughly examined by a specially trained dermatologist under the microscope straight away to see if all the basal cell carcinoma has been removed. It differs from a ‘frozen section’ in that all of the cut surface is examined making the chance of any basal cell carcinoma being left behind extremely small. If any residual basal cell carcinoma is found at the edge of the excision, further skin is removed from that area and examined under the microscope and this process is continued until all the basal cell carcinoma is removed.
This is a time consuming process and only undertaken for certain basal cell carcinomas in difficult anatomical areas if simpler surgery is not suitable.
Other types of treatment are sometimes used for basal cell carcinoma, but these are rarely used for basal cell carcinomas around the eye. These treatments are usually given by dermatologists and include:
- Curettage and cautery: the basal cell carcinoma is scraped away (curettage) and the skin surface is sealed (cautery).
- Cryotherapy: freezing the basal cell carcinoma with a very cold substance (liquid nitrogen).
- Radiotherapy: directing x-rays onto the area containing the basal cell carcinoma.
- Creams: applying creams to the basal cell carcinoma. The two most commonly used are 5-fluorouracil (5-FU) and imiquimod (Aldara).
- Photodynamic therapy: a special cream is applied to the basal cell carcinoma which is taken up by the cells that are then destroyed by exposure to a specific wavelength of light.
- Drug therapy: very rarely, drugs can be used for very advanced basal cell carcinomas that are not able to be treated by other means.
Surgical removal is the preferred treatment but the choice of treatment depends on the site and size of the basal cell carcinoma, the condition of the surrounding skin and number of basal cell carcinomas to be treated (some people have many) as well as the overall state of health of each person to be treated.
How will my eyelid be repaired after the basal cell carcinoma is removed?
The main priority with surgery is to remove all of the basal cell carcinoma. Equally importantly, the eyelids should be repaired to make them look as much like they did before and to have them function as well as before, opening and closing like normal.
After the basal cell carcinoma is removed, smaller gaps in the eyelids or the skin around the eye can be repaired so that the eye will look and function much like it did before. However, for larger basal cell carcinomas the surgery to repair the eyelids may leave visible scars and the appearance of the eyelids will not be quite the same. For example, reconstructed eyelids will often not have eyelashes in the area where the eyelid has been reconstructed.
Sometimes skin is moved from next to a gap where a basal cell carcinoma has been removed (a skin flap), or skin can be transplanted from some other part of the body (such as behind the ear) to repair a gap in the skin (a skin graft). Because the eyelids also have a moist lining that sits against the eye, some repairs need to replace this lining as well. Extra lining can be taken from under the top eyelid or other places such as the lining of the mouth which has similar moist tissue that keeps the surface of the eye healthy. It is not always possible to predict how the eyelids or area around the eye will be repaired, because the amount of skin that has to be removed to get rid of the basal cell carcinoma completely is sometimes greater than was predicted at the time the basal cell carcinoma was first examined.
Will I get other basal cell carcinomas?
If you have one basal cell carcinoma there is a high chance you will either get one at some time in the future or that you may have another and perhaps be unaware of it. For these reasons, it is a good idea to have your skin properly examined by your GP or by a dermatologist.
What can I do?
Treatment will be much easier if your basal cell carcinoma is detected early. It is advisable to see your doctor if you have any marks or scabs on your skin which are growing, bleeding, never completely healing or changing appearance in any way.
Check your skin for changes once a month. A friend or family member can help you particularly with checking your back.
You can also take some simple precautions to help prevent a basal cell carcinoma appearing:
- Protect the skin with clothing, including a hat, t-shirt and UV protective sunglasses.
- Spend time in the shade between 11am and 3pm when it is sunny.
- Use a ‘high protection’ sunscreen e.g. SPF 30 which also has high UVA protection, and make sure you apply it generously and frequently when in the sun.
- Keep babies and young children completely out of direct sunlight.
