Actinic keratoses

Overview

Actinic keratoses are skin changes that develop as a result of years of UV exposure. They appear as rough, scaly, sometimes reddish patches, particularly on the so-called sun-exposed areas such as the face, ears, scalp (in cases of baldness), backs of the hands and forearms. Actinic keratoses are regarded as an early form or precursor of light-skinned (non-melanoma) skin cancer and should be medically assessed and treated.

Several methods are available for treatment. For widespread changes (field cancerisation), photodynamic therapy (PDT) is an established procedure with which larger areas can be treated 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 following medical assessment

Procedure

1. Examination and choice of therapy

   First, we assess the skin changes and determine the appropriate procedure. If there is any uncertainty, a fine-tissue (histological) examination may be advisable.

2. Photodynamic therapy – applying the active substance

   The affected areas are treated with a cream that contains a light-activatable active substance. This is taken up primarily by the altered cells.

3. Incubation time

   The area is then covered to protect it from light – for classic PDT, for about three hours, so that the active substance accumulates in the altered cells.

4. 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 required, the treatment can be repeated after 10–14 days.

5. Alternative procedures

   Depending on the findings, ablative lasers (erbium-YAG or fractional CO₂ laser), freezing (cryotherapy) or creams for self-application may also be considered. We will discuss with you which procedure is best suited.

What to expect

• During illumination, classic PDT can burn or hurt – sometimes considerably; if needed, we cool the area or pause. The daylight variant („Daylight PDT“) is usually considerably less painful, but requires a longer illumination time.
• For a few days after treatment, redness, swelling and crusting in the treated area are common.
• With PDT, larger, widespread areas can be treated in a single session.
• Afterwards, please protect the treated areas consistently from sunlight.
• Where medically necessary, the treatment is generally covered by statutory health insurance; we discuss the scope in advance.

Risks & notes

• Redness, burning, swelling and crusting can occur temporarily; the skin is sensitive to light after treatment.
• Not every change responds completely – follow-up appointments and, if necessary, a repeat treatment are important.
• If a finding remains unclear or changes, a fine-tissue examination is necessary to confirm the diagnosis.
• Photodynamic therapy is only suitable for superficial forms (e.g. superficial basal cell carcinoma, Bowen's disease); nodular or more deeply growing tumours and invasive light-skinned (non-melanoma) skin cancer are treated differently – usually surgically. Before such a treatment, we generally confirm the diagnosis by fine-tissue examination.
• In the case of certain light-sensitive conditions (e.g. porphyria) or an intolerance to the light-activatable active substance, PDT is not suitable – we clarify this in advance.
• After illumination, please protect the treated area consistently (generally for at least 48 hours) from sunlight; on rare occasions, temporary pigment shifts or, very rarely, small scars may remain.
• Since actinic keratoses are an expression of generally sun-damaged skin, regular skin checks and consistent sun protection are important.

Frequently asked questions

Are actinic keratoses dangerous?

They are regarded as an early form or precursor of light-skinned (non-melanoma) skin cancer. Individual changes are usually readily treatable; if left untreated, they can develop over time into light-skinned (non-melanoma) skin cancer. For this reason, they should be medically assessed and treated.

What is photodynamic therapy?

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

Does the treatment hurt?

Classic PDT can burn or hurt during illumination – sometimes considerably; if needed, the area is cooled or the treatment is paused. The daylight variant is usually considerably less painful.