Summary of Procedure

Summary of the Metvix^® Procedure

• For BCC and BD, Metvix^® is conducted in two sessions, one week apart.
• For AK,  Metvix^® is performed in one session which can be repeated after three months if necessary.

Multiple lesions can be treated during the same session. To ensure optimal outcomes, only a physician trained in this technique should conduct the procedure, assisted by a nurse or other trained medical/technical personnel as appropriate.

1. Lesion Preparation

Before administration of topical Metvix^® cream, the affected area is prepared to enable optimal access of the cream to tumour tissue and to maximise light penetration. The type of preparation is dependent upon the type of lesion being treated, but will involve the gentle removal of the surface layer of the lesion.⁴ Normally scales and crusts should be removed and the surface of the lesions roughened. Any intact epidermal keratin layer on nodular BCCs should be removed. Material should not be excised beyond the tumour margins and exposed tumour material should be removed gently.

2. Metvix^® cream application

Metvix^® cream is applied in a 1 mm thick layer to the lesion and 5-10 mm of surrounding normal tissue. The surrounding tissue is included to ensure that all of the tumour cells are treated, as some tumour cells may be present within the borders of normal tissue.⁴

The affected area is covered for three hours with an occlusive dressing enabling the active ingredient to be absorbed and produce PAPs in tumour cells. Although the patient is free to move around the clinic at this time, he/she should probably not venture outside if the conditions are adverse. Coldness can stimulate vasoconstriction and limit the formation of protoporphyrin and oxygen. Warm weather conditions can cause patients to sweat and cause cream migration.

3. Illumination

After three hours, the dressing and excess Metvix^® cream are gently removed and the affected area is illuminated under red light (e.g. Aktilite lamp (by clicking on this link you will be leaving this site - Galderma is not responsible for the content)) at a distance of 5 to 8 cm. This illumination will take approximately 7-9 minutes.⁴ The total light dose should be 37 J/cm2 and the light intensity should not exceed 200 mW/cm2 at the lesion surface. Protective eyewear is recommended for the patient and physician to avoid any temporary discomfort.

4. Aftercare

Areas treated may be cooled with water-soaked gauze or cold thermal water spray.

As a general precaution, sun exposure on the treated lesion sites and surrounding skin has to be avoided for a couple of days following treatment. Optimal lesion healing is best assured when sun exposure on the treatment area is minimised for six weeks.

Crusting may occur, and this is normal. The treated area should remain undisturbed and can be dried after washing by gentle dabbing. Healing generally occurs between 3-6 weeks.

5. Assessment/Repetition

The treatment is repeated after 1 week for BCC and BD.

A review of clinical response can be made after 6-8 weeks and a decision made on the timing of the next evaluation, necessity for biopsy or retreatment. Treatment of AKs can be repeated after 3 months if required.

6. Patient Management

Clinical trials have shown that Metvix^® is a safe and well tolerated treatment for BCC and AK with predictable and easily manageable side-effects.⁷

Typical side effects are a burning, stinging or prickling sensation early during the illumination, restricted to the treatment area. Analgesia is not necessary in the majority of cases. If this is found necessary, lidocaine or bupivicaine without adrenalin works well in practice.

Erythema, oedema, crusting and peeling may occur post treatment. Most side effects were described as being of mild to moderate intensity and of short duration. ^{4, 9-12}

See Patient Management for further practical advice including minimisation of pain.

For a video of the procedure please click here.

References