Photodynamic Therapy using a Topical Photosensitizer

Following a consultation with Dr. Searles he may recommend PDT treatment as being suitable for you.

    • PDT is used as an alternative to surgery for the treatment of Actinic Keratoses (AK) and certain types of Basal cell carcinomas (BCC) on the face and scalp.
    • Methyl aminolevulinate (Methyl-ALA) is a substance that is specifically absorbed into the altered skin cells of these lesions. Methyl-ALA causes compounds called porphyrins to accumulate and be absorbed selectively by the AK and BCC lesions. These porphyrins are light sensitive, so when the Metvix® is illuminated and activated by an appropriate light source it causes a chemical reaction in the skin cells that destroys the lesion.
    • Methyl-ALA-PDT requires two treatment sessions, 7 days apart, to ensure the lesion is adequately destroyed.
    • Before commencing treatment you must ensure you are available for both sessions.

     

    Precautions and contraindications

    • Methyl-ALA contains peanut oil. Peanuts are a known allergy.
    • Methyl-ALA may cause sensitization of skin on contact and rarely may cause local skin reactions such as contact dermatitis.
    • Any UV therapy should be discontinued before treatment.
    • As a general precaution avoid sun exposure on the treated area for a couple of days following treatment.
    • There is no data on Methyl-ALA and exposed pregnancies and reproductive toxicity studies have not been performed on animals so Metvix® is not recommended during pregnancy.
    • In the absence of clinical experience breastfeeding should be discontinued for 48 hours after application of Methyl-ALA cream.
    • Treatment will not be performed if you are sunburnt or have significantly tanned skin (this includes fake tan applications).
    • Let your Nurse know if you have a history of cold sores as Methyl-ALA-PDT treatments can trigger herpes simplex activation. You may be prescribed an anti-viral medication for prevention of cold sores.



    Treatment

    Day of treatment:
    Having already seen Dr. Searles you will now need to see the PDT nurse to go over expectations of treatment and ensure you understand everything about the procedure before signing consent forms.

    • A 15-minute appointment will be booked for you to have the Methyl-ALA applied to the lesions to be treated, which will then be covered with a flesh coloured dressing.
    • There is a 3-hour waiting period for the Methyl-ALA cream to be absorbed. You can leave the surgery during this time but you must leave the protective dressings intact.
    • When you return to the office the Metvix® will be washed off and immediately illuminated with a red light, the intensity and time exposed to red light depends on the type of lesion we are treating. Light exposure can be anywhere between 8-20 minutes.

    Follow-up appointments:

    • 7 days after first treatment you will need to have your second treatment.
    • You will then be required to attend the clinic for follow up appointments with the PDT nurse 7 days after your second treatment.
    • 1 month after your second treatment you will need to see the PDT nurse for a follow up.
    • You are then expected to see your consulting Dermatologist 3 months later for a skin check to assess cure of the treated lesions and detect any new lesions.
    • As you are prone to these pre-cancerous and cancerous lesions from past sun exposure it is recommended you have ongoing skin checks with your dermatologist or GP for detection and treatment of any new lesions.





    Before Methyl-ALA

    After Methyl-ALA




    After care

    • Leave treated area uncovered.
    • Clean as normal in shower, using the mild cetaphil face wash provided.
    • You will have been given a prescription to take to the pharmacist and get a tube of fucidic acid ointment.
    • Treated lesions are to be kept moist with Fucidic acid applied 3x a day for 7 days to encourage re-epithelialisation
    • If in an area where clothing will irritate then cover with micropore tape and apply fucidin over the top of tape which will soak in.
    • Make sure all your follow up appointments are booked
    • Following Methyl-ALA PDT, you may experience a burning or stinging sensation and some degree of pain. These reactions are generally transient and of mild to moderate intensity. swelling and erythema may also occur and a crust may form over treated lesion
    • If there is excessive swelling and redness post operatively the patient will need to see their dermatologist for consideration of systemic anti-inflammatories etc.
    • If pain continues post treatment Ibuprofen is recommended every 4-6 hours and cooling with ice packs.
    • Your skin will be sensitive and a bit fragile following treatment so as a precaution avoid direct sunlight for a couple of days after treatment.
    • Sunscreen needs to be applied everyday even in Winter and if the sun is not out.
    • Make sure you use a broad spectrum 30+ sunscreen specific for use on the face. If you are unsure about the product you are currently using or want advice on sunscreen, your nurse can discuss and recommend a sunscreen product suitable for your skin type.

    Side effects

    Expected side effects:

    • There is an element of pain during treatment
    • Burning and stinging sensation at time of light activation
    • Crusting of lesions treated
    • Swelling and redness at treatment site that can last up to a week or two.

    Common side effects:
    • Ulceration of lesion treated
    • Blistering
    • Erosion
    • Peeling
    • Hyper or hypo pigmentation ( a darkening or lightening of the skin at area treated)

     

    Pain Management


    • Most people tolerate treatment with a mild discomfort level being reported.
    • A Mild pain killer is advised to take the edge off any anxiety and reduce the level of pain you may feel. Try not to have any stimulant drinks at least 2 hours before treatment such as coffee, tea, Red Bull as these heighten anxiety and can intensify the pain you may feel.
    • It is advisable that you take 2x Ibuprofen tablets 1 hour before your Illumination appointment. If stinging and burning is experienced following treatment continue to take Ibuprofen every 4-6 hours and ice with ice packs provided.
    • A fan may be used during treatment by your nurse to cool the skin if you start feeling pain or discomfort during treatment.
    • If the pain you experience during treatment is unbearable then treatment can be ceased and a local anesthetic injected into the lesion to numb it. As most people don't unnecessarily want injections this is only done if necessary.

     

    Download our Patient Information Sheet on this technology.