What is Photodynamic therapy?
Photodynamic therapy (PDT) is a technique used for the treatment of various skin cancers. The technique has largely replaced liquid nitrogen therapy in most modern dermatology clinics. The treatment involves the application of a light sensitising cream to the treatment area and the subsequent exposure of that area to light.
Which skin cancers can be treated by Photodynamic therapy?
Photodynamic therapy (PDT) is used for the treatment of Solar Keratosis, Basal Cell Carcinomas, and Bowens disease.
Is photodynamic therapy still an experimental treatment?
No, photodynamic therapy has been used since 1988 and have been extensively investigated and subjected to many clinical trials. You can search the PUBMED medical database to view the available published research into the subject.
How is the treatment done?
Rough spots in the treatment area are lightly scraped and a cream is then applied over the whole treatment area. The cream is left on for 1-3 hours. During this time you may leave the surgery, but most of our patients choose to stay in the clinic. After 1-3 hours the excess cream is wiped off and the area is exposed to a specific light source for 20 minutes. If the lesion is a basal cell carcinoma the procedure is repeated after 7 days.
What exactly happens during the treatment?
After the cream is applied the cancerous cells absorb the cream while the normal skin cells do not. The cream is converted inside the cancerous cell to a chemical that is extremely sensitive to red and blue light. After 1-3 hours the chemical is, for practical purposes, only present in cancerous cells and not present in normal skin cells. When the red or blue light is shone on the skin the chemical becomes activated and free radicals are formed inside the cancer cells. These free radicals then kill the cancer cells.
What does the treatment feel like?
It depends on how long the cream was left on the skin and what type of pain relief you have. If the cream is left on for about and hour, no pain relief is generally necessary. Most patients describe the pain at around a 4 /10, with 10/10 being very painfull and 0/10 no pain.
If the cream is left on for about 2 hours an oral analgesic can be used for pain relief. Most patients describe the pain at around a 6-8 /10, with 10/10 being very painfull and 0/10 no pain.
If the cream is left on for more than 2 hours conscious sedation or other pain relief techniques are used.
The size of the area that needs to be treated also influences the degree of discomfort. If a small area is treated the treatment is done under local anaesthetic and therefore painless.
What are the side effects following treatment?
Very common side effects are a burning sensation, stinging sensation, pain, swelling, crusting and redness. Less common side effects include itchiness, ulceration, suppuration, blisters, peeling, skin infection, hyperpigmentation and hypopigmentation. Urticaria is a rare side-effect.
What are the advantages of PDT over other treatments?
PDT destroys only cancerous cells and not normal cells. It is therefore selective and scarring is extremely unlikely. Liquid nitrogen therapy, surgery and curettage & cautery have a significant risk of scarring. Liquid nitrogen therapy very often leaves white spots following treatment. With PDT these side-effects are much less likely. PDT also results in significant skin texture improvement and has a general rejuvenating effect in the treatment area.
How effective is Photodynamic therapy compared to other treatments?
Clinical cure rates of Photodynamic therapy is similar to all the other treatment options, but has significant cosmetic advantages and does not affect normal cells.
What are the medical aid codes in South Africa for the treatment?
0191, 0202, 0286, Nappi code: 700004001
What does the treatment cost?
It depends on the size of the involved area, but generally between R1500 and R1900. Conscious sedation, if used, adds to the cost of the treatment.
What happens when I arrive at the surgery for photodynamic therapy treatment?
- The area to be treated will be lightly scraped with a curette and wiped with acetone to remove any residue that could inhibit the absorption of the PDT cream.
- The PDT cream will then be applied.
- The cream will be left in place for 1 – 3 hours.
- Depending on how long the cream is left on, you will either stay in the practice or leave the practice, but should completely avoid all sun exposure.
What happens after the PDT cream is removed?
- The light will be positioned over the area that needs treatment and you will then be exposed to a red or blue light source for 20 minutes.
- During the treatment you will experience a varying degree of pain. The longer the cream was left on, the more intense the pain will be.
- Another 1 or 2 treatments might be required at 4-6 week intervals, to achieve optimal results.
What happens after the treatment has been completed?
DAY 0-2 after treatment:
- The treated area will feel hot and burning for 3-24 hours.
- Cold compresses and analgesics will help to relieve the sensation.
- You will also experience a varying degree of pain in the treated area that can be relieved by taking Paracetamol (e.g. Panado, Compral) and NSAIDS (e.g. Voltaren, Brufen) 4-6
hourly. - Forehead treatment can lead to upper eyelid swelling and puffiness.
DAY 2-5 after treatment:
- You will experience crusting, scaling and redness.
- Regular use of Vaseline or Bactroban will help to keep the area smooth and prevent cracking.
DAY 5-7
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By day 7 the area should nice and smooth, but will be slightly red. Some mild scaling might still be present
- The redness will fade over weeks.
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The intensity of these sensations is directly correlated to how badly sun damaged your skin is.
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Regular (3 hourly) application of a SPF 30+ sunscreen is essential for at least 6 weeks.
G’day Doc,
Just a quick query mate; I’ve been diagnosed with PXE (Pseudo Xanthro Elasticum) approx seven years ago. The skin spec I’m currently has recommended I try this treatment. It hasn’t been done in Australia yet and if it works, the treatment will assist so many people!
What is/are your recommendations on my spec’s thoughts?
Cheers
Dear Kurt. PXE affects the dermis (the middle layer of the skin). The cream that is applied when doing photodynamic therapy generally penetrates only into the epidermis. I therefore do not think that PDT can have a major effect on the skin signs of PXE. PDT have been used by ophthalmologists to treat angioid streaks, which is an eye problem associated with PXE.
Dear Dr. Louw
It has been recommended that my mother, aged 71, undergoes photodynamic therapy for BCC and general sun damage. I am interested to know the name of the applied cream that you will be using as I have had treatment here in Hong Kong using just cream which caused redness, blistering and crusting over and just wondered if you were using a similar thing.
Thank you
Judith Stevenson
Dear Judith. The cream that I use for Photodynamic therapy of general sun damage contains the active ingredient 5-aminolaevulinic acid (5-ALA).
Dear Dr Louw,
Does PDT cure malignant melanoma?
Dear Bev. PDT is not a treatment option for Malignant Melanoma.
Hi Dr Louw, I have sun spots on different places on my face and also a bit on my chest, Will this treatment work for me? and does my medical aid cover this treatment?
Dear Frederik. If what you have is solar keratosis, then yes it will work. Medical aids do not always cover the treatment….
Dear Doc
I am not familiar with the correct medical terms of my condition and would appreciate your help and I would also like to come and see you as I live around the corner. To put it in plain english, my face is covered with frecles which I would like to get rid of and also reduce the size of my pores. Is this possible? I also have some mols I would like to remove. Please be so kind to reply to my e-mail with details.
Kind regards
Ryan
Dear Ryan. All of it is possible to some extent. The specific treatments depend on the exact type, size and positions of the relevant lesions.
Will this treatment also be beneficial for severe ichting over large parts of the body due to eczema and allergic rashes?
Dear Helena. No, not at all. The indications are limited to what I mention in the above article.
Good day Dr Jeanne,
I am from South Africa. I was dicnosed with skin Cancer on my nose in 2002 ( Basal cell carcinoma) I had 2 skin transplant operations already but it keeps re-apearing. My last treatment i had was Aldara cream for 6 weeks. But know it apeard on two other places. I need to get help in South Africa, and wounder if you perhaps know of a doctor or someone I can see… Or could recomend a treatment as I am so scared that I am going to lose my nose. Please consider comming back to me on this.. I have photo’s aswell.
thank you
Alida Potgieter
South Africa
Dear Alida. If you can, come and show me. Photodynamic therapy might be a good option for you. There are different types of basal cell carcinoma. Some can be treated very effectively with photodynamic therapy. The big advantage of photodynamic therapy is that there are no scarring. But, let us make a diagnosis first and we can then discuss the treatment options.
Gooday Dr.
I went for 2 Photodynamic Therapy treatments
however not to treat any sort of cancer but for scars on my cheeks left behind by acne!
im a bit concerned as i read through your article on Photodynamic Therapy and nothing is mentioned of It treating acne!
is this a problem? as i didnt see any results either
Dear Tasneem. PDT can be used for active acne in specific cases. It is generally not used to treat actual scarring.
Dear Dr Louw
I recently had PDT treatment done by a Dermatologist at the UCT Skin and Hair Clinic, as I had a precancerous spot on my lower lip. I was given the literature to read in preparation. I am however not sure if this PDT treatment was performed correctly as there was no reaction on the actual spot I was concerned about, but the other part of my lip reacted. The procedure was as follows: I had some cream applied to my lip and covered with plastic and tinfoil. I waited 3 hours and was then given local aneasthetic, and cream was applied to my lip once more. I was put under the light and had water continuously sprayed on my lip while under the light, but it appeared the water was concentrated on the side of my lip where the spot is. Would this much water have affected the outcome i.e. whether the treatment was successful.
I will appreciate your professional opinion
Kind regards
Belinda Johnstone
Dear Belinda. The spraying of the water will have no effect on the efficacy of the treatment. The reason is that the cream applied for 3 hours would have been absorbed into the pre-cancerous cells and can therefore not be washed off. The spraying of water is sometimes done to relieve pain.
I was told to wash the affected area twice a day with salt water and rub gently, not to worry if it bleeds. Quite traumatic and painful to do this. Is this the acceptable treatment?
Dear Dr Louw, I am due to undergo this treatment on Friday 21st January. The Doctor concerned has stated that the cream that will be applied will be left for approximately 3 hours. According to this article “concious sedation” should be used or other pain relief techniques if the cream is left on for more than 2 hours. What is “Concious Sedation” and what other “Pain Relief” techniques are available and what can I ask from the Doctor concerned re this pain relief and the pain relief after the treatment?
Sincerely,
John Finlayson
Dear John. It is best to discuss this with your doctor. If a small area (say less than a few cm) will be treated then local anaesthetic can be used. If it is a big part of the face for example then the procedure gets more painful the longer the cream is left on. “Conscious Sedation” is a type of general anaesthetic done by an anaesthetist in the dermatologists room. You can also take common pain relief tablets prior to the procedure, but their efficacy for pain relief during PDT is limited.
Hi. I would like PDT (PHOTODYNAMIC THERAPY) to be done on my tongue as I have been diagnosed with a tumor there. where can I have this performed and who can I contact in South Africa to assist me. I am desperate and it is urgent.
hi. I would like to have PDT(photodynamic therapy) for my tongue which doctors state cancer cells in. Could you help me as to where I could have this treatment. I am really desperate.where can it be performed or who I
I was suggested photodynamic therapy to get rid of severe brown sun spots on my arms and legs.Reading above,this doesnt sound correct for my needs?
Dear C. Collins. No, PDT is not used to treat hyperpigmentation. Hyperpigmentation sometimes improves when doing PDT, because the pre-cancerous cells that PDT treat can also contain pigment. Hyperpigmentation is better treated with a laser that targets melanin pigment.
Dear Dr. Louw,
During the exposure to 20min of intense ‘phototherapy,’ does this mean that the normal skin will suffer from ‘sunburn’?
Dear Louise. No, “sunburn” is a result of DNA damage due to exposure to ultraviolet B radiation. PDT makes use of a red light, not ultraviolet light, that activates the applied cream. Skin that did not absorb the cream is not affected.