About Photodynamic therapy
Photodynamic therapy is a safe and effective non-surgical treatment for certain low risk skin cancers (e.g. superficial basal cell carcinoma and intraepidermal carcinoma/Bowen’s disease), and for precancerous lesions such as actinic keratoses (sun spots).
PDT utilises photosensitising medication, oxygen and light, to create a photochemical reaction that selectively destroys cancer cells, and minimizes injury to normal skin cells.
The main advantage of PDT is that it can eradicate the above lesions with typically excellent cosmetic result, and allows one to avoid the surgical scars that invariably result from surgical procedures. It can also avoid some of the other complications of surgery, such as the risks of infection, dehiscence and prolonged discomfort/sensation changes after surgery.
PDT treatment involves the following steps to be completed within the same day:
Metvix® PDF treatment procedure
Then REPEAT 1-4 weeks later for superficial basal cell carcinoma and intraepidermal carcinoma.
Due to the non-invasive and selective nature of the treatment, the potential for scarring and side effects are minimised, however some pain & redness of the area may occur. Within a few days, the exposed skin and BCC will scab over and flake away.
Minimal aftercare is needed. Simple analgesia (e.g. paracetamol) may help with the minor discomfort. An ointment such as Vaseline or white soft paraffin can help speed skin healing.
Photodynamic therapy for superficial basal cell carcinoma (sBCC) and intraepidermal carcinoma (IEC)
Studies have shown that PDT can give cure rates of 85% to 90% for appropriately selected superficial BCC (sBCC) and intraepidermal carcinoma (IEC/SCC in situ/Bowen’s disease). Nodular BCC are less responsive to PDT, but can be treated in appropriate circumstances.
PDT is not suitable for melanoma or squamous cell carcinoma, or higher risk BCC (e.g. morpheic, sclerosing, micronodular), recurrent BCC (lesions which have recurred after previous treatment), or thick BCC (lesions greater than 2mm in depth).
A skin biopsy is usually recommended prior to treating lesions to confirm the diagnosis and to make sure the lesion is of correct subtype to respond to the treatment.
PDT for Actinic keratoses (AK)
Actinic keratoses (sunspots) are pre-cancerous lesions. Whilst mild lesions are sometimes observed, more advanced lesions are usually treated. A small percentage of actinic keratoses progress to squamous cell carcinoma (a potentially very dangerous skin cancer which requires surgery). Actinic keratoses are also often cosmetically obvious, scaly and irritable, and thus benefit from treatment.
Actinic keratoses usually occur in a field of solar damage, with clinically visible lesions combined with subclinical lesions (not readily visible). Field treatment may be suggested. Suitable field treatments include topical creams (5-fluorouracil, imiquimod, ingenol mebutate), and PDT.
A Follow up appointment is usually made 3 months post treatment to check the effectiveness of the procedure. Late recurrence is possible, so a check yearly for a few years is also advised. Also, if you have developed one skin cancer there is a high risk (perhaps 40%) of developing further skin cancers elsewhere on your skin in the future. Regular skin checks are helpful. Sun protection and sun avoidance can reduce the risk of future skin cancer.