How do skin cancers start?
Exposure to the sun is considered the primary risk factor. A genetic pre-disposition, fair skin and northern European descent are also considered risk factors.
It is important not to neglect skin spots that appear irregular, grow in size, ulcerate or that bleed. You should always check with your local doctor if you are concerned about your skin. If your Doctor is unsure about a spot or skin marking, they can refer you to a Radiation Oncologist or a Dermatologist.
Each year more than 430,000 Australians are treated for skin cancer. This usually involves local excision by general practitioners, dermatologists, and plastic surgeons. However, for certain types of skin cancer there is an additional treatment option that should be considered.
A Radiation Oncologist or a Dermatologist with experience can often tell whether a skin spot is cancerous or not by simply examining it. In order to confirm the diagnosis, your doctor may perform a punch biopsy, which is when a small circle (2 to 5mm) of the superficial skin is cut out under local anaesthetic and sent to a pathologist for microscopic evaluation. If the lesion is not too large, your doctor may perform an excisional biopsy, which is when the whole lesion is cut out.
At other times, surgery presents a difficult proposition due to co-existing medical problems, and in such cases radiotherapy may be used alone.
Satisfactory cosmesis may also be difficult to obtain following surgery if a skin cancer arises in a challenging site such as in proximity to the eyes, ears, nose, and lips. In these situations radiotherapy can be a good alternative.
Can Radiotherapy be used to treat skin cancer?
Skin cancers are the most common form of cancer affecting all Australians. Radiotherapy is an effective treatment used to treat superficial skin cancers that are not melanomas.
In some circumstances, following surgery, radiotherapy can be used to reduce the risk of skin cancers, including melanomas, recurring.
Skin cancers that are not melanomas are basal cell carcinomas (BCC), the most common and Squamous cell carcinomas (SCC) the next most common and are generally more aggressive than BCCs as they have a tendency to spread through the bloodstream and lymphatics.
Treating BCCs and SCCs
BCCs and SCCs can be cured in most instances if treated early.
Surgery is usually the most common form of treatment in younger patients. However, if the lesion is not cut out entirely (close or positive surgical margins) or the risk of it recurring is high because it is aggressive (grade 3) or exhibits invasion of nerve tissue (perineural invasion), then radiotherapy is recommended as well.
Superficial radiotherapy is of benefit also to patients who cannot have surgery or patients with very large skin cancers that would otherwise require extensive surgery and grafting or if the cancer is in an awkward position, such as the face, where surgery would be deforming. You can always request an opinion from a Radiation Oncologist
Radiotherapy for BCCs and SCCs
Superficial radiotherapy provides excellent cure rates for superficial BCCs and SCCs as well as pre-cancerous conditions such as Bowen's disease or sun spots that could turn into cancer.
The outcomes are equal to that of surgery with proven cure rates of 95% and higher, and often the cosmetic result is much better than surgery which may require skin grafts or leave deformities.
Treatment is quick, invisible and pain-free and usually conducted once – twice or up to 5 times per week over 4 to 6 weeks.
The advantage of superficial radiotherapy is that can be used for a number of different patients, who can't have other treatments, such as patients who:
- Are medically unfit for surgery or too frail for a general anaesthetic.
- Have multiple or widespread skin cancers, which would require major reconstructive surgery involving skin grafting.
- Have reasons why they can't have surgery, including medications such as warfarin, which thins the blood, making surgery dangerous.
- Require treatments to difficult areas, such as the head and neck region, where the risks of incomplete excision, damage to normal, important structures and poor cosmetic outcomes are extremely high.
- Are at a very high risk of recurrence of the cancer following surgery alone, with risk factors for recurrence such as incomplete excision, tumours that are poorly differentiated (grade 3) or that invade nerve tissue (perineural invasion).