Photodynamic therapy – PDT – for baby skin cancers and acne

Chronic sun damage, with blotchy pigmentation and bits of red and brown and scaly things some people call skin cancers but doctors call “solar keratoses“: that’s your skin – but what do you do about it?


Your GP, or your skin cancer doctor, or your dermatologist, will attack these “solar keratoses“, or “actinic keratoses“, or “skin cancers” (even though they are not true skin cancers) with liquid nitrogen, freezing them with a blast. Every time they do that, you get a blister, then a scab, then it heals with a big white spot.


You’re sick of doctors blasting away at these things leaving you all spotty!


In such cases the best approach today is Photodynamic Therapy (PDT). With photodynamic therapy it is possible to specifically destroy the abnormal cells of solar keratoses before they become apparent to the naked eye. Therefore, visible solar keratoses are prevented. The treatment leaves a smooth finish without any risk of white marks, and the whole face is treated at a single session.


For this reason anyone with persistently sun-damaged skin should look at Photodynamic Therapy as a way of evening out their colour and texture. The laying down of new collagen and a closing effect on pores occurs as well, all contributing to a better looking skin.


Photodynamic therapy is also a powerful anti-acne tool. Photodynamic therapy works to destroy the overactive cells lining the acneic skin glands. When nothing else is helping your acne Photodynamic Therapy is your most potent weapon without resorting to oral medication.


What does the process involve?


The process of Photodynamic therapy first involves a session of microdermabrasion. This clears some of the surface flaking and creates a smoother and receptive skin surface for the next step, which is the application of a solution of 5aminolevulinic acid.


5aminolevulinic acid, or 5ALA, is produced naturally in our cells and is converted into protoporphyrin 9 (PP9). Protoporphyrin 9 is very sensitive to light, and under exposure to light PP9 will create substances that can destroy the cell. Usually, though, there are only very tiny quantities of PP9 in our cells, and they are illuminated without risk.


However, if a solution of 5ALA is applied onto the skin, then metabolically active cells like SK cells will rapidly soak up the 5ALA and will convert it to an oversupply of PP9. Other, normal epidermal cells do this very slowly. So, after an hour or so following the application, the SK cells are very sensitive to light, and your normal cells are not.


The third step involves the application of light. We use the Omnilux as a continuous source of very bright 630nm light that will activate 5ALA causing the PP9 to kill the cells in which its concentration is high, which are SK cells and, by the way, active cells at the base of acne lesions and sebaceous glands. Normal cells remain.


We need you for two hours at least to perform photodynamic therapy. 30 minutes for the microdermabrasion, at least an hour for the 5ALA application (for most of that you are just resting and waiting), then at least half an hour for the light treatment. You will find the microdermabrasion quite comfortable and even relaxing. The 5ALA application may sting at first, but will settle in minutes.


The third part of the treatment, under the light, may hardly bother you at all or it may be quite painful, depending on the amount of sun damage on your face and the concentration of 5ALA we have used.


What happens afterwards?


As the hours pass after the treatment, your skin will become red. You may feel like the area has been sunburnt (although it has not). The following day your face is likely to be quite red, and you may not want to go to work or do anything social. You may want to take Panadol or Nurofen, and apply cool packs to the skin. Be reassured, then, that the more the redness in the short term, the better the result in the longer term.


Other possible treatments for solar keratoses include prescribed creams, electrocautery and surgery. In the great majority of cases we have found that these other treatments do not offer any advantage over a combination of cryotherapy and photodynamic therapy for solar keratoses. There are, of course, lots of options for sun-damaged skin and for acne as well. We discuss all your options in consultation with Dr Mahony.


At a consultation a treatment program for your skin can be designed using the best of all treatment modalities as applied in your own specific case.