Management cont.
Cryosurgery is a long-established treatment for AKs requiring a cryospray (or cotton wool and orange sticks) and a supply of liquid nitrogen. Complete clearance rates vary according to the duration of freeze and the number of treatments, usually separated by 6–12 weeks. Cryotherapy should involve a single freeze-thaw cycle of approximately ten seconds (avoid the gaiter area of the legs due to risk of leg ulceration). Cryosurgery is a flexible therapy that requires skill in administration. With larger doses it is likely to result in loss of pigment and scarring. Patient counselling is important concerning the short- and long-term side-effects. In particular, patients should be aware of blistering, oedema, crusting and soreness. Doses appropriate for AK are usually < 10 s, but still carry some risk of damage to underlying structures such as tendons and nerves if applied on the back of the hands. Below the knee, slow healing can be a problem, particularly in the older patient group presenting with AK.
Efudix ® cream (5-FU) - apply every night for four weeks. Wash hands thoroughly after application. Leave treated areas uncovered and wash the following morning. Patients should be advised to expect a relatively mild degree of redness and discomfort during the treatment period
Actikerall ® solution is a new treatment combining 5-FU with salicylic acid. It is licensed for treating moderately thick hyperkeratotic AKs. It should be used once a day for 6-12 weeks.
For smaller areas of field change (e.g. an area the size of a palm or most of the forehead) consider the following treatments;
Aldara ® cream (5% imiquimod)
- Use three nights a week e.g. Monday, Wednesday and Friday for four weeks. Apply overnight and wash off the following morning. After four weeks stop the treatment and consider the use of a mild topical steroid e.g. 1% Hydrocortisone or Eumovate ® cream BD for two to four weeks to help settle down any inflammation. Follow up three months after the treatment was started, repeat the treatment if needed.
- The advantages are it’s generally very effective in terms of clearance, and cosmetic appearance once inflammation resolved.
- The disadvantages are patients should be warned to expect marked erythema with crusting of the skin. Timing of the treatment is important and is best avoided during holidays and important social occasions. Some patients develop flu-like symptoms during treatment.
Efudix ® cream (5-FU)
- Used once a day for four weeks. Apply thinly in an evening with a gloved finger, alternatively wash the finger after application. The treated area should be washed the following morning. After four weeks stop the treatment and consider the use of a mild topical steroid eg 1% Hydrocortisone or Eumovate ® cream BD for two to four weeks to help settle down any inflammation. Follow up three months after the treatment was started.
- Advantages and disadvantages similar to those that occur with Aldara ®, although patients do not develop flu-like symptoms.
- It is important that the patients are counselled about the side effects including soreness, redness and possible crusting. All of these can be minimised through reduction in the frequency of application or short breaks in a course of therapy. It is permitted to wash the area and apply thin emollient. It is important that the patient is enabled to learn how to use the treatment, as it is one they may require intermittently in the future and a bad initial experience can limit further use. (BAD)
- Use at poor healing sites such as the lower leg should always be undertaken with caution and may need supervision. More recently, 5-FU 0 5% in 10% salicylic acid has been evaluated and can be prescribed. (BAD)
Picato ® gel (ingenol mebutate, as 150 µg/g or 500 µg/g)
- A new treatment.
- Advantages are similar to the outcomes detailed above, but in addition a very short treatment period and recovery phase when compared to the other topical treatments.
- For the face and scalp - apply the 150 µg/g formula for 3 consecutive days only.
- For the trunk and extremities - apply the 500 µg/g formula for 2 consecutive days only
Photodynamic therapy
- This is provided by some dermatology departments and occasionally GPwSI clinics.
A single treatment often provides an effective treatment for an area of field change. The skin settles down within a few days of treatment. Cosmetic outcomes are good.