Photodynamic Therapy

Photodynamic therapy may be used for treating certain skin cancers and precancers.
It is used mainly for actinic keratoses, intraepidermal carcinoma , erythroplasia of Queyrat and superficial basal cell carcinomas (<2mm thick)
A photosensitiser (methylaminolaevulinate) in cream form is applied to the affected area. 3 hours later the area is exposed to red light for 15 minutes. The light activates the methylaminolaevulinate which has been absorbed by the tumour which then converts molecular oxygen to cytotoxic singlet oxygen and free radicals causing ischaemic necrosis of the tumour by damaging cell membranes , especially those of blood vessels.

It has the advantage of being non-invasive and can be carried out in an outpatient setting
Several areas can be treated at once
It rarely causes ulceration and there is a good cosmetic result
There is good patient acceptability
It is useful for treating tumours on sites that are difficult surgically

For further information see:

Metvix Photodynamic therapy (119k)
Photodynamic therapy post treatment information (95k)