'Actinic keratosis' is a medical term which is derived from the Greek words 'aktis' and 'keras', meaning 'ray' and 'horn', and actinic keratosis (or 'AK) then regards a hornization [keratinization] of the skin, which is considered to occur through damage inflicted by UV radiation, which is a reason why also the term 'solar keratosis' is used.1, 2, 3, 4
The occurrences of actinic keratosis may strongly vary. Third grade actinic keratoses may be centimetres large with thick keratinization, hyperpigmentation and inflammation, while first grade actinic keratoses may be smaller than a millimetre and are with a thin, skin coloured keratinization sometimes hardly visible. In the latter case they are only visible as dull and palpable as rough spots. Actinic keratoses may occur solitary, but often more actinic keratoses occur (a difference which here shall be indicated as 'spot' versus 'field').5, 6
Although it doesn't occur often, actinic keratoses have the potential to evolve in later stages into non-melanoma skin cancers.7, 8 Treatment is with low grade, solitary actinic keratoses not necessary, but with the increase of the development grade and the numbers, also the recommendations for treatment increase.9
Actinic keratoses occur often. The lighter the skin type, the higher the age and the longer the exposure to the sun, the larger the chance for development of actinic keratoses becomes. A large majority of elderly with a light skin type gets to do with actinic keratoses.10, 11, , 12
There is a wide range of treatments possible. Cryotherapy for instance is popular with doctors and suited for spot treatment. Thereby liquid nitrogen is sprayed on the spot, because of which the actinic keratosis freezes. Possibly a blister develops, which dries, and with the falling of the scab, healthy cells have taken the place of the damaged cells. Advantages of cryotherapy are that it is cheap and fast. Anaesthesia's are also not necessary. Disadvantage is however that also healthy tissue is frozen. Added to that the treatment demands some expertise: when frozen too shortly the actinic keratosis may return, but when frozen too long a scar may develop. Cryotherapy is not suited for field treatment.13, 14
Laser therapy may also be applied for spot treatment. Hereby the actinic keratosis is after a local anaesthesia as it were evaporated with a CO2 laser. The advantage of laser therapy over cryotherapy is that there is less risk of scar formation. The treating clinic however must invest in equipment and skills. And also with laser therapy healthy surrounding tissue is treated along.15, 16
Curettage and electro coagulation can be used when the actinic keratosis is high grade and thick. Here after anaesthesia the actinic keratosis is removed with a sharp spoon, after which the tissue is removed and closed by burning. This treatment has a higher risk of leaving scars and is less suited for low grade actinic keratoses, and evidently not suited for field treatment. Also with this treatment healthy tissue is treated along.17, 18
For field treatment 5-fluorouracil cream is popular with doctors, and it can also be used for spot treatment. This '5FU' cream is in the Netherlands on the market as 'Efudix'. The treatment is actually a chemo therapy on the skin, which slows down the cell growth of the damaged cells, because of which they die off. Advantages are that the cream is cheap and only targets damaged cells. Also not yet visible damaged spots are targeted. Disadvantage is the length of the therapy. Where in the Anglo-Saxon countries still usually a treatment of two weeks is held up, in the Netherlands four weeks is the standard, and this is excluding the time of recovery after the treatment. Also skin reactions may be considerable, with inflammations and wound and scab forming. Besides that 5FU may be absorbed systemically, because of which possibly complaints may rise which are comparable to those with systemic chemotherapy.19, 20, 21, 22
With a relatively new therapy 5-florouracil is mixed with calcipotriol, a substance which is normally used for psoriasis. The length of treatment is with this therapy shortened to approximately four days, whereby a strong immune reaction is triggered to selectively remove damaged cells. Also the systemic absorption of substances is therewith of course significantly reduced. A disadvantage is that this therapy is not yet approved by the medical authorities. In the Anglo-Saxon countries the therapy is nevertheless already plentiful applied, and here and there in Belgium and the Netherlands there are also already doctors who apply the therapy.23
Imiquimod cream, in the Netherlands on the market as 'Aldara', is also applied for actinic keratoses. Also this therapy works selectively on the damaged cells through the activating of the immune system. Disadvantages are that also this cream has to be smeared for weeks and that the treatment thereby can be accompanied with side effects such as skin reactions, but sometimes also with systemic reactions with flu-like symptoms.24, 25
Photodynamic therapy (PDT) also works selectively on, both visible and invisible, damaged spots. A cream with the light sensitive aminolevuline acid ('ALA-PDT') or methylaminolevulinate ('MAL-PDT') is applied on the to be treated field or the to be treated spot. The last mentioned substance is on the Dutch market available as 'Metvix'. Damaged cells absorb the aforementioned substance easily, and when that substance is activated by light of a certain frequency, the damaged cells are destroyed.
With PDT a differentiation is made between conventional or red light PDT and daylight PDT. With red light PDT the cream is after the application sealed and given three to four hours to be absorbed, after which red light is directed to the to be treated skin. And with daylight PDT is, after the application and the absorption of a sunscreen cream, the MAL cream applied, after which within thirty minutes the skin is approximately two hours exposed to daylight or light of a daylight lamp.
The results of red light PDT and daylight PDT are comparable with mild actinic keratoses, but with actinic keratoses of higher grades red light PDT is recommended. Red light PDT is usually experienced as more painful than daylight PDT, which is almost painless. With both therapies skin reactions may occur. The advantage of PDT is the short treatment time, and daylight PDT can even be done at home. Disadvantage is the high price of MAL cream and the needed investment in red light and possibly daylight lamps.26, 27, 28, 29, 30
Australian livestock farmers noticed that the application of pulp of the fruits of devil's apple, a plant in the night shade family to which also the egg plant belongs, could result in regression of eye cancer with their animals. Dr. Bill Eliot Cham has researched this and isolated the active substance, BEC, which is also found in egg plants and consists of solasodine glycosides, and processed it in a medical salve, Curaderm BEC5, which with application destroys damaged cells. Diverse clinical tests have proven this activity, and besides that there are many testimonies of users that acknowledge this activity. Curaderm can successfully be used with skin cancer and actinic keratosis.31, 32
BEC clears damaged cells through the reactivating of their programmed cell death (opoptosis), which in these cells became disturbed (or in greater doses possibly through oncosis or cell swelling). Hereby BEC only interacts with damaged cells, and healthy cells stay thus unharmed.33, 34
According to the published guidelines, Curaderm can be applied for non-melanoma skin cancers and for actinic keratoses. For skin cancers the cream is applied and covered with occlusive tape to prevent drying out. With the clearing of the damaged cells then a wound will develop which heals by itself when all damaged cells are removed. With this treatment the cream must be applied until the formed wound is closed.35, 36
In the case of actinic keratosis may, dependent on the grade, a treatment of seventy two hours suffice, whereby at least every twelve hours Curaderm is freshly applied. Older guidelines prescribe the use of occlusive tape thereby, however according to newer guide lines this is not needed during daytime. And for the treatments of both skin cancer and actinic keratosis it is valid that more numerous applications of the cream speed up the healing process.37, 38, 39
The use of Curaderm BEC5 with actinic keratosis offers diverse advantages over the earlier mentioned treatments. Cryo-, laser and curettage therapies for instance may last only moments but don't spare the healthy skin. Curaderm however works selectively on damaged cells.
The mentioned chemical creams work also selectively, but these therapies last for weeks, because of which their chemical components can also be absorbed systemically. BEC in Curaderm however is a natural product extracted from egg plants and is besides that not systemically absorbed. Added to that, the dose BEC in Curaderm has shown to be completely safe, and the treatment of actinic keratosis with a maximal indicated treatment time of three days and nights is short.40, 41
Now it can be objected that the chemical creams are better suitable for field treatment and therewith also target invisible damaged spots. However also Curaderm targets invisible damaged spots when applied, and the remedy is clinically successfully tested with (smaller) field directed treatments.42
PDT may also be applied as field treatment, but the MAL cream is expensive, and all mentioned field directed therapies may give considerable side effects on the healthy skin. Curaderm may also give side effects on the healthy skin because of the assisting substances, salicylic acid and urea, which are added to break down the keratin layer, but these substances are also found in many skin care products, and the active substance BEC itself does not give side effects on the healthy skin and may be processed in creams without the aforementioned assisting substances, such as for instance in the sunscreen cream Curasol. In that case BEC may work preventative on a daily base with the removal of not visible damaged cells. Hereby still red spots may occur, but this then indicates the working of BEC on the damaged cells, and by treating these spots then one or two days with Curaderm, the elimination process is sped up.43, 44
Another important advantage of Curaderm over the other mentioned therapies is that Curaderm is available without prescription. This gives the patient control over his own treatment. If the actinic keratoses are low grade and small in size or number, a doctor may decide that treatment isn't needed and withhold the patient the regular therapies. With Curaderm the patient always has a treatment option at his disposal.
Actinic keratosis often occurs with people with a light skin type. There are many different treatments possible. However these treatments do not spare the healthy skin, give risks for scarring, are chemical in nature, take long, and / or may give many side effects, also on the healthy skin and / or systemically. Added to that are all these treatments only accessible with doctor prescriptions. Curaderm then offers an accessible, natural, selective and relatively quick treatment with little risks for side effects and scarring. All doctors and patients that get to do with actinic keratosis should therefore be familiar with Curaderm. May this publication then contribute to that.