Blue-light therapy warding off skin cancer

Photodynamic, or "blue-light," therapy at University of Iowa Hospitals & Clinics is helping dermatologists ward off skin cancer in patients with actinic keratoses. 

Also known as solar keratoses, these scaly bumps range in size from pinhead to one inch and appear primarily in sun-exposed areas on the face, ears, head, lips, forearms, and back of the hands. If left untreated, an estimated 10 percent of these precancerous lesions may eventually evolve into a type of skin cancer called squamous cell carcinoma. 

Blue-light therapy for actinic keratosis can help treat and reduce the number of precancers, potentially reducing the number of full-fledged skin cancers, and helping in photo-rejuvenation. In addition, photodynamic therapy can treat large areas of the patient's skin, usually with little discomfort, and offers some advantages over other treatment methods. Many people, even those with diabetes, are candidates for the therapy. People with rare light-sensitive conditions, however, cannot receive the treatment. 

Pioneered in Europe, the therapy works by applying a light-sensitizing chemical solution to the skin area that needs treatment and then exposing the area to blue light. The photosensitive chemicals, which have been absorbed into the skin, react with the particular wavelength of blue light to generate reactive oxygen radicals that destroy the potentially precancerous or cancerous skin cells. 

An alternative to traditional methods

Longer-standing treatments for actinic keratosis include cryotherapy, topical chemotherapy, and resurfacing.

• Cryotherapy, which involves freezing the skin with liquid nitrogen, is quick and effective. However, unlike blue-light therapy, it can sting and is not practical to use for large areas of skin. 
• Topical chemotherapy can treat a large skin area but often causes inflammation.
• Chemical or laser resurfacing can be used to remove skin layers. This method can treat large areas but can be uncomfortable. 

Photodynamic therapy is a helpful alternative method for treating actinic keratosis. It's proactive and to some extent, preventative. 

People who work in farming or spend a lot of time outdoors without using sunscreen or protective clothing are at risk of developing actinic keratosis. In addition, people with fair skin, blonde or red hair, or blue, green, or gray eyes are most at risk. However, even individuals with darker complexions can be at risk if they receive a lot of sun exposure. 

What to expect when being treated

Photodynamic treatment involves an initial screening followed by a treatment visit.

During the treatment visit the photosensitizing liquid, aminolevulinic acid, is applied to the patient's affected skin. The patient sits in a darkened room for about an hour while the liquid is absorbed. Then, the target area is exposed to blue light for about 17 minutes. Patients wear protective eye goggles while undergoing the light treatment. 

The treated lesions heal in about a week, however, the therapy makes people temporarily more sensitive to sunlight and sunburn. As a result, patients must use sunscreen and sun-protective clothing for the 24 to 48 hours immediately after treatment. 

As with all medical care it is best to consult your personal doctor before making any changes to your health care routine.