Precancerous lesions (Actinic Keratosis) are discrete, scaling, rough lesions that occur on areas of chronic sun damage. These occur frequently in fair skin individuals secondary to prolonged and repeated sun exposure. Common locations include the ears, face, scalp and the upper extremities. Actinic Keratosis are pre-cancerous because a small number of them may progress to becoming Squamous Cell Carcinomas. Thus, treating them is very important.
Treatment modalities include freezing with liquid nitrogen, topical creams like Aldara, Efudex, Carac and now new treatment methods like Photodynamic Therapy (PDT) with Levulan.
What is an Actinic Keratosis (Precancerous lesions)?
Actinic Keratosis are pre-cancerous lesions that must be treated in order to prevent them from progressing to skin cancer. On clinical examination, they present as small rough areas on a background of photodamage. Clinically, the patient can see them and also feel the rough areas. These rough areas are a representation of actinic keratoses.
How to treat Precancerous lesions (Actinic Keratosis)?
There are multiple ways of treating these precancerous lesions. Classically, liquid nitrogen has been used. Typically, these lesions are spayed upon for about 5 to 10 seconds and then thawed. This process could be repeated multiple times. The patient will come back in 2 to 4 weeks and the same procedure will be repeated again. If the lesions do not disappear after several sessions of freezing with liquid nitrogen, then a biopsy may be warranted to determine that these lesions have not progressed to become a Squamous Cell skin cancer.
Other treatment modalities include Efudex. Efudex has classically been used to treat areas of sun damage as well as precancerous lesions. Efudex which is 5-fluorouracil comes in various strengths. It is typically used twice a day for about 2 weeks. The areas of treatment will become red, scaly, rough, and sometimes even tender. Dr. Behnam uses Efudex along with Bactroban in order to prevent any infections. Dr. Behnam always warn patients that they are going to be red for about 4 to 5 weeks.
It is very important to wear sunscreen during the day. Dr. Behnam typically prescribe Efudex during the wintertime. There are other creams that are similar to Efudex such as Carac as well as Aldara, both used in the same way as Efudex. After one finishes with the course of Efudex, which typically takes about 2 weeks, the redness will slowly resolve itself over the next few weeks. The skin will eventually be less rough and scaly. Also some of the brown sunspot areas may go away. In some cases, the patients may look about 5 to 10 years younger depending upon the reactions of the Efudex.
Some patients might respond to Efudex more aggressively than others. The reaction depends upon the underlying amount of sun damage. The more sun damage you have on your face, the more brisk the Efudex response is going to be. For example, a 35-year-old white male who has protected himself from the sun all his life will not react as briskly as a 55-year-old white male who has been a surfer all his life.
Precancerous lesions and lasers?
One of the most recent treatments for pre-cancerous lesions (Actinic Keratosis) has been the photodynamic therapy, also known as PDT. In this case, chemicals, such as Levulan or Metvixia, are applied to the entire face. The chemical is left on for about an hour. This chemical is preferentially absorbed by the precancerous lesion. Once absorbed the chemical must be activated by a laser. In our clinic, Dr. Behnam use the Omnilux red laser in order to activate theses chemicals.
Once the chemical becomes activated, it kills the precancerous lesions that have absorbed that chemical. By doing so, the clinical results are very similar to Efudex, but the reaction is less severe.
The patient’s area of treatment will become red, scaly, and crusty, depending upon the amount of sun damage and precancerous lesions in the area. The redness and crusting might last anywhere between 1 to 2 weeks. In most cases photodynamic light therapy with Levulan or Metvixia produces a less brisk reaction than using Efudex.
For the first 48 hours, patients will be very sun sensitive and it is very important to wear a lot of sunscreen when out in the sun. In fact immediately after the patient has finished the photodynamic therapy with Levulan or Metvixia in our clinic, sunscreen is applied and the patient wears a hat before leaving the clinic.
Patients may need to repeat the photodynamic light therapy every 6 weeks for few sessions. Overall photodynamic light therapy with Levulan or Metvixia is a great treatment for the treatment of actinic keratosis and precancerous lesions.
Photodynamic light therapy protocol for treating precancerous lesions
- The patient arrives an hour early to clinic.
- Face is cleansed with alcohol and chemical Levulan or Metvixia is applied to the face.
- The chemical incubates for about 1 hour in the clinic.
- The chemical is then removed and the patient sits under Omnilux red light for a specified period of time.
- After the duration of time has elapsed, the laser is turned off the laser. Heavy sunscreen is applied on the patient’s face.
- The patient wears a hat and leaves the clinic. The patient should avoid the sun for the next 48 hours.
- The patient return to clinic in 4 to 6 weeks for follow-up.
If the area that was treated needs additional treatment, then the patient is scheduled for additional treatment in 6 weeks.
Can Photodynamic light therapy be used on the face?
One of the benefits of photodynamic light therapy is that it could be used on any area that has tons of sun damage. These include the hands, forearms, as well as the chest. Again one of the biggest benefits of photodynamic light therapy is that it will get rid of precancerous lesion. This is very important because precancerous lesions can progress to squamous cell carcinomas, a form of skin cancer. Aggressive and early treatment of precancerous lesions will prevent skin cancer. That is why it is so important that these will be treated with the various modalities mentioned above.
Dr. Behnam is a skin cancer specialist and is very adamant about treating precancerous lesions and actinic keratosis at an early stage. If any patient feels any rough spots on the face or forearms, it is highly recommend to see your dermatologist to treat the pre-cancerous lesions at an early stage.