Comparison of red and green light in the treatment of Bowen's disease by photodynamic therapy.
BACKGROUND
A variety of protocols exist for the treatment of Bowen's disease by photodynamic therapy (PDT) using topical 5-aminolaevulinic acid (5-ALA).


OBJECTIVE
To determine the optimal wavelength (red or green light) for this treatment.


METHODS
A randomized comparison study of ALA-PDT using red (630 +/- 15 nm) or green (540 +/- 15 nm) light in the treatment of Bowen's disease.


RESULTS
The initial clearance rate for lesions treated by red light was 94% (30 of 32) in comparison with 72% (21 of 29) for those lesions receiving green light (P = 0.002). Over the following 12 months, there were two recurrences in the red light group and seven in the green light group reducing the clearance rates to 88% and 48%, respectively. The frequency and severity of pain experienced were similar between the two treatment groups. No hyperthermia, nor significant difference in lesional temperatures, was observed between the wavelengths studied.


CONCLUSIONS
Green light is less effective than red light, at a theoretically equivalent dose, in the treatment of Bowen's disease by topical ALA-PDT.
Morton
C A
CA
University Department of Dermatology, Western Infirmary, Glasgow G11 6NT, UK. camorton@fdri2.fdri.scot.nhs.uk
Whitehurst
C
C
Moore
J V
JV
MacKie
R M
RM
D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid / Q000627:therapeutic use; D001913:Bowen's Disease / Q000188:drug therapy*; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use; D012878:Skin Neoplasms / Q000188:drug therapy*
D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid