Are actinic keratoses dangerous?

They count as an early form or precursor of non-melanoma skin cancer. Individual changes are usually easy to treat; left untreated, they can turn into non-melanoma skin cancer over time. That is why they should be medically assessed and treated.

What is photodynamic therapy?

A method in which a light-activatable active substance is applied to the skin and, after an incubation time, irradiated with special light. This damages the altered cells. It suits widespread changes particularly well.

Does the treatment hurt?

During the illumination, classic PDT can burn or hurt, at times considerably; if needed the area is cooled or the treatment is paused. The daylight variant is usually considerably less painful.

Can photodynamic therapy be combined with a laser treatment?

With heavily sun-damaged skin, the combination of the fractional CO₂ laser and photodynamic therapy comes into question. Whether it makes sense in an individual case depends on the findings and is discussed with you beforehand. The fractional CO₂ laser is described on the page of the same name in our aesthetics section.

Actinic keratoses

Actinic keratoses are sun-induced skin changes and an early form of non-melanoma skin cancer. They can be treated with photodynamic therapy (PDT), among other methods.

Overview

Actinic keratoses are skin changes caused by years of UV exposure. They show up as rough, scaly, sometimes reddish patches, above all on the so-called sun terraces such as the face, ears, scalp (where a person is bald), backs of the hands and forearms. They count as an early form or precursor of non-melanoma skin cancer and should be medically assessed and treated.

There are several options for treatment. With widespread changes (field cancerisation), photodynamic therapy (PDT) is established; it can treat larger areas in a single session.

Areas of application

Actinic keratoses (single or widespread)
Field cancerisation (several changes within one area)
Bowen's disease
Superficial basal cell carcinomas after medical assessment

Procedure

Examination and choice of therapy
First we assess the skin changes and determine the suitable method. If anything remains unclear, an examination under the microscope (histology) can make sense.
Photodynamic therapy: applying the active substance
The affected areas are treated with a cream that contains a light-activatable active substance. It is taken up above all by the altered cells.
Incubation time
The area is then covered so that light cannot reach it, with classic PDT for about three hours, so that the active substance accumulates in the altered cells.
Illumination
Afterwards the area is irradiated with cold red light from a special lamp for around ten minutes; this selectively damages the altered cells. If needed, the treatment can be repeated after 10–14 days.
Alternative methods
Depending on the findings, ablative lasers (erbium-YAG or fractional CO₂ laser), freezing (cryotherapy) or creams for self-application also come into question. We discuss with you which method fits best.

What to expect

During the illumination, classic PDT can burn or hurt, at times considerably; if needed we cool the area or pause. The daylight variant (“daylight PDT”) is usually considerably less painful, but it needs a longer illumination time.
For a few days after the treatment, redness, swelling and crusting in the treated area are common.
With PDT, larger, widespread areas can be treated in a single session.
Please protect the treated areas consistently from sunlight afterwards.
Where there is medical necessity, the treatment is as a rule covered by statutory health insurance; we discuss the scope beforehand.

Risks & notes

Redness, burning, swelling and crusts can occur temporarily; the skin is sensitive to light after the treatment.
Not every change responds fully. Check-up appointments and, where needed, a repeat treatment matter.
If a finding remains unclear or changes, an examination under the microscope is necessary to confirm the diagnosis.
Photodynamic therapy is suitable only for superficial forms (e.g. superficial basal cell carcinoma, Bowen's disease); nodular or more deeply growing tumours and invasive non-melanoma skin cancer are treated differently, usually surgically. Before such a treatment we as a rule confirm the diagnosis by examining the tissue under the microscope.
With certain light-sensitive conditions (e.g. porphyria) or an intolerance to the light-activatable active substance, PDT is not suitable. We clarify this beforehand.
After the illumination, protect the treated area consistently from sunlight (as a rule for at least 48 hours); rarely, temporary pigment shifts or, very rarely, small scars remain.
Since actinic keratoses are an expression of skin that is sun-damaged overall, regular skin checks and consistent sun protection matter.

Frequently asked questions

Are actinic keratoses dangerous?: They count as an early form or precursor of non-melanoma skin cancer. Individual changes are usually easy to treat; left untreated, they can turn into non-melanoma skin cancer over time. That is why they should be medically assessed and treated.
What is photodynamic therapy?: A method in which a light-activatable active substance is applied to the skin and, after an incubation time, irradiated with special light. This damages the altered cells. It suits widespread changes particularly well.
Does the treatment hurt?: During the illumination, classic PDT can burn or hurt, at times considerably; if needed the area is cooled or the treatment is paused. The daylight variant is usually considerably less painful.
Can photodynamic therapy be combined with a laser treatment?: With heavily sun-damaged skin, the combination of the fractional CO₂ laser and photodynamic therapy comes into question. Whether it makes sense in an individual case depends on the findings and is discussed with you beforehand. The fractional CO₂ laser is described on the page of the same name in our aesthetics section.