About Basal Cell Carcinoma
The most common skin cancer is the Basal Cell Carcinoma (BCC), it is also the most widespread form of all cancers. It accounts for about 66% of all skin cancers diagnosed in Australia.
Along with Squamous Cell Carcinomas (SCC) they are grouped as non-melanoma skin cancers. It is estimated that there are about 600,000 Basal Cell Carcinomas diagnosed and treated in Australia each year.
When the body’s basal cells undergo abnormal, uncontrolled growth, a Basal Cell Carcinoma will form. They often occur when DNA damage from exposure to ultraviolet (UV) radiation from the sun or indoor tanning, for example, triggers changes in basal cells. This happens in the epidermis, the outermost layer of skin.
The Basal Cell Carcinoma may not develop directly after sun exposure, in fact a Basal Cell Carcinoma usually develops many years after the excessive sun exposure takes place. There are some people who have a higher risk of developing Basal Cell Carcinomas, these typically include people who have fair skin, people with a strong family history of Basal Cell Carcinoma and those with Celtic ancestry.
Thankfully, Basal Cell Carcinomas rarely spread beyond the original tumor site. However, if not detected and treated early they will grow and these lesions can be disfiguring and dangerous. Untreated Basal Cell Carcinomas can become locally invasive, grow wide and deep into the skin destroying skin, tissue and bone, which is why it is so important to have regular skin check-ups.
After having a single Basal Cell Carcinoma it is more likely that another may develop. There is, on average, a 50% chance of a person developing another Basal Cell Carcinoma after having a single Basal Cell Carcinoma. After having developed four or more Basal Cell Carcinoma, the chance of developing another is very high, greater than 90%.
As Basal Cell Carcinomas are caused by exposure to the sun, they usually develop on parts of the body that are most often unprotected, such as the head, face, shoulders, arms and lower legs.
They often start with a subtle change in the skin, like a small bump or a flat red patch. Signs of a Basal Cell Carcinoma to look for include:
– a pearly spot or lump
– a scaly, dry area that is shiny and pale or bright pink in colour (although some Basal Cell Carcinoma are darker)
– a sore that doesn’t heal
– a sore that bleeds
Types of Basal Cell Carcinoma
Superficial Basal Cell Carcinoma
Superficial Basal Cell Carcinomas are confined to the very top layers of the skin so are often more easily treated with topical and non-surgical techniques. Superficial Basal Cell Carcinomas can however become relatively broad in size and are particularly common on the trunk of the body.
Nodular Basal Cell Carcinoma
Nodular Basal Cell Carcinomas usually appears as a rounded lump on the skin. They are less likely to have invisible extension under the surface of the skin than other types of Basal Cell Carcinoma.
Infiltrating Basal Cell Carcinoma
These are the most troublesome type of Basal Cell Carcinoma as they are usually larger than they appear to
the naked eye. They are usually the most difficult to see and are often not detected until
well advanced.
Treatment of Basal Cell Carcinoma
If your Skin doctor has identified a potential Basal Cell Carcinoma, a biopsy (a small sample of the lesion) is usually taken and sent to the pathology laboratory to be examined under the microscope to confirm the diagnosis and the type. Once the type of Basal Cell Carcinomahas been confirmed, there are a variety of treatment methods. The Skin Specialist will determine the most appropriate method, given the person’s health and age, the size and site of the lesion and the type of Basal Cell Carcinoma.
Standard Surgical Excision (removal)
This is the most common and the most effective form of treatment for Basal Cell Carcinomas. It involves cutting out the lesion with a safety margin and suturing (stitching) the skin back together. It is standard practice to remove the lesion with a 2-4mm safety margin to minimise the chance of leaving any tumor cells behind. The cure rate is greater than 95% with this technique.
Serial Cryotherapy
This involves spraying the tumor with liquid nitrogen. The freeze time is prolonged and multiple freeze thaw-cycles may be used. This method is mainly used to treat superficial Basal Cell Carcinomas. This form of treatment is quick, inexpensive, and has a good cure rate when treating superficial lesions. Serial cryotherapy is less often used in cosmetically sensitive or highly
visible areas due to its higher risk of scarring.
Curettage and Cautery
Curettage and cautery involves injection of local anesthetic, followed by scraping the lesion from the skin with a curette and then cauterisation of the base. It typically heals with a pale scar. The cure rate is generally in the vicinity of 90% with this technique when used on
appropriately superficial lesions. It is often used for superficial Basal Cell Carcinoma and very small nodular Basal Cell Carcinomas on the trunk and limbs of the body.
Topical Immunotherapy
Topical immunotherapy involves using a special cream for up to 6 weeks. This cream works by stimulating the body’s own immune system to fight and destroy the skin cancer cells. Typically the area will become inflamed and scaly during the period of treatment. It is only appropriate for certain superficial and low-grade lesions and its cure rate is 80% or less.