By far the most important cause of skin cancer is sun exposure. The sun is NOT your friend. Avoid excessive sun exposure, and especially avoid a severe, blistering sunburn. That tan that makes you look young and healthy, when you already are young and healthy, will make you look old and wrinkled before your time!
When you must be in the sun, use a sunblock with an SPF of at least 15. The products with a higher SPF can block a bit more ultraviolet, but only until they wear off or wash off. If you swim, or perspire, or towel off, renew your sunblock for protection.
There are two main kinds of skin cancers: basal cell carcinomas and squamous cell carcinomas. These have different appearances and your dermatologist can often be rather sure which is which. Even experts can be mistaken, however, so a biopsy is always recommended. Basal cell cancers grow more slowly and can invade deeply, but they almost never spread through the lymph nodes or bloodstream. Squamous cancers tend to grow more quickly, and they sometimes do spread.
(A third, and much more serious type of skin cancer is melanoma. Its connection to sun exposure is much less strong. Melanoma is more likely to spread than other skin cancers, and requires much more aggressive treatment. You should see your doctor promptly if you have any of the classic signs of melanoma: a new or changing skin blemish that is bluish or black, that has irregular edges, that has patchy coloration, or that has inflammation, crusting or bleeding. Melanoma is always treated by surgery.)
Skin cancers occur mostly on areas that have had sun exposure. The face, ears, neck, and hands are common places.
Most basal and squamous cancers are treated by surgery. When there is plentiful surrounding skin to close the surgical wound, this is usually the treatment of choice. Radiation therapy should be considered, however, for skin cancers in places where plastic surgery will be needed to close the defect, or where the cosmetic outcome is important. Radiation therapy can give a cure rate equal to surgery, and often a better cosmetic outcome with the need for complicated repairs. It is particularly useful for cancers on the ears, nose, eyelids and lips.
Radiation therapy is also able to cure skin cancers that have reoccurred after surgery. These cancers usually have come back because they have “deep roots” – extension into normal tissues that is difficult to detect. When a really complicated surgery is contemplated, radiation therapy should be considered as an alternative because it can usually treat a larger area that surgery, with less resulting deformity.
Most centers treat skin cancers with the electron beam, a form of radiation made by a standard linear accelerator in which the penetration of the beam can be limited to a depth chosen by the radiation oncologist. Usually, a series of daily treatments for four to six weeks are required.
At Inova Fairfax Hospital we are able to treat superficial basal and squamous skin cancers using a technique called high dose rate (HDR) skin brachytherapy. HDR skin brachytherapy deposits the optimum intensity of therapeutic radiation right at the skin surface, and the intensity falls off very quickly with further skin penetration. This is precisely the distribution of radiation dose that works best for superficial skin cancers. This treatment can usually be completed in only two to three weeks.