Potential Impact of Patient Vitamin D Status in AK Response to MAL-PDT
Condition: Actinic Keratosis
MeSH terms: Keratosis, Actinic; Keratosis
Study type: Interventional

Summary: 
      In topical photodynamic therapy (PDT) for non-melanoma skin cancers, a photosensitizing
      prodrug, 5-aminolaevulinic acid (ALA) or its methylated ester, methyl aminolevulinate (MAL),
      is converted to the endogenous photosensitizer protoporphyrinIX (PpIX).

      Reduced response rates are observed in thicker skin lesions, which may be due to insufficient
      PpIX accumulation within the target tissue.

      To enhance PpIX production,several physical and chemical pretreatments have been suggested.
      One of the chemical substances proposed to stimulate PpIX production is vitamin D because of
      its ability of being a keratinocyte pro-differentiating hormone.

      Based on in vitro and in animal model studies, we propose to study the potential impact of
      patient vitamin D pre-treatment in AK response to MAL-PDT.
    

Detailed description: 
      A randomized, controlled Split -scalp study with Calcipotriol Assisted MAL-PDT versus
      conventional MAL-PDT for actinic keratosis (AK) is proposed.

      Twenty patients ( male gender only) with symmetrically distributed multiple AK lesions on the
      scalp will be included. Patients must have at least five AKs per field to be eligible.

      After simple randomization, one half of the scalp will be treated with Calcipotriol ointment
      50 mcg/g (Daivonex, Leo Pharma, Denmark) for 15 consecutive days.

      After this period, the entire scalp will be submitted to topical PDT with
      Methylaminolevulinate 16% (Metvix, Galderma France) under occlusion for 90 minutes and then,
      illuminated with a light source consisting of a Light Emitting Diode device (LED) at 635 nm (
      Aktilite - Photocure, Norway). The total light dose will be 37J/cm2.

      Immediately before and after illumination with LED, measurements of the fluorescence
      intensity will be taken in 3 isolated spots in both sides of the scalp with a spectroscopy
      deviceUSB 2000+ ( Ocean Optics ® - Dunedin, Fl, USA).

      AK lesions will be counted and mapped by a dermatologist not involved in the study before and
      after 3 months.

      All patients will be advised to apply sunscreens 50 + 3x/day for the following 7 days after
      the procedure.

      A 0-10 Visual Analogue Scale (VAS) will be used to measure the pain intensity during the
      illumination.

      Records will be taken after 90 days and compared between sides: side effects, AK lesion
      response and pain level intensity. Also, a long term follow up will be provided at 6 and 12
      months after.
    

Intervention name(s): Conventional MAL-PDT; Calcipotriol assisted MAL-PDT
Intervention type(s): Other; Other
Intervention description(s): Curettage of lesions and application of MAl cream 16% for 90 minutes under occlusion followed by LED 635 nm illumination at 37 J/cm2 total dose; Calcipotriol 50 mcg/g for 15 days prior to PDT. Curettage of lesions and application of MAl cream 16% for 90 minutes under occlusion followed by LED 635 nm illumination at 37 J/cm2 total dose
Intervention MeSH terms: Calcipotriene
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: PDT; skin cancer; calcipotriol