Photodynamic therapy (PDT) is a treatment option for several skin cancers.
In particular, PDT has been be used for:
PDT is NOT used to treat:
- Invasive SCCs
- Melanoma of any type
- Other grades of BCC
What is involved in the treatment?
The PDT treatment takes place at the doctor’s surgery. The cream is applied to the tumour and then covered with a dressing. The patient then waits a few hours for the light sensitizing to have effect. The patient then has the treatment area subjected to a specific red and / or blue light beam for a specified accurate length of time.
The skin surface needs to be exposed to the air at the time. That is for PDT to work, the cream and the light and air are all needed.
A repeat treatment is typically organized 7 to 14 days later.
When PDT is used for actinic keratoses often an area rather than a specific lesion is being treated. The cream is applied to larger area such as part or all of the face. Then the light is applied to this larger area.
Does it work?
PDT has proved to be very disappointing. When used to treat cancers we know the recurrence rates are very high, and often the tumour is more aggressive when it recurs.
When PDT is used to treat sun damage it usually improves the appearance of the skin. However growing evidence shows cancers are not prevented.
PDT causes immune suppression in the skin. This is probably why it works poorly on skin cancers and does not appear to lower or risk of developing new skin cancers.
These can be a problem. It hurts when the light is shining on the skin. Some patients can't tolerate it. Once the treatment is over, the area can be very red and weepy until it recovers. The "hip pocket" side effect is often the one that is greatest concern to patients.
Talk to your doctor about Metvix PDT and whether it is right for you and your tumour.