title: Fractional carbon dioxide laser improves nodular basal cell carcinoma treatment with photodynamic therapy with methyl 5-aminolevulinate.
abstract: BACKGROUND
  The major limitation of photodynamic therapy with 5-aminolevulinic acid (ALA-PDT) is proper photosensitizer penetration. The nodular form of BCC (nBCC) is perceived as a contraindication to ALA-PDT because the tumor layer is thicker than 2 mm. We have improved on the results of previous studies that used an ablative laser to limit tumor thickness. A fractional laser produces skin microtubules that can improve the penetration of ALA into tumors.
  
  
  OBJECTIVE
  To evaluate the use of a fractional laser as pretreatment before ALA-PDT for nBCC treatment in an 18-month single-blind clinical trial.
  
  
  METHODS
  Fifty-six verified nBCCs were ablated using a diode laser under ultrasound control. Half of the tumors were treated 3 weeks later using a fractional carbon dioxide laser, and the other half were treated using curettage (control). We then immediately treated with ALA-PDT. Fluorescence and photography were evaluated and compared each month, and a final histopathologic examination was performed.
  
  
  RESULTS
  Fifty-two of 56 nBCCs in the fractional laser treatment group responded to ALA-PDT, compared with only 45 of 56 in the control group. Fluorescence was higher in 53 cases in the treatment group; 3 cases demonstrated the same fluorescence level in both groups. Healing took longer in the treatment group, and there were more side effects.
  
  
  CONCLUSIONS
  Fractional laser pretreatment increases the fluorescence and clinical effectiveness of ALA-PDT for the treatment of nBCC.
authors.affiliation: Department of Photonic Medicine, 1st Medical Faculty, Charles University, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Lippert
authors.forename: Roman
authors.initials: R
authors.lastname: Smucler
authors.forename: Marek
authors.initials: M
authors.lastname: Vlk
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives*; D002280:Basal Cell Carcinoma / Q000473:pathology / Q000601:surgery*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D054020:Lasers, Gas / Q000627:therapeutic use*; D008297:Male; D008870:Microtubules; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000473:pathology; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D012878:Skin Neoplasms / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome
chemical_list: D017319:Photosensitizing Agents; C475457:methyl 5-aminolevulinate; D000622:Aminolevulinic Acid