Topical photodynamic therapy in the treatment of actinic keratoses and Bowen's disease in transplant recipients.
BACKGROUND
Transplant recipients (TR) have a dramatically increased risk for widespread epithelial neoplasms of the skin. Thus, there is a need to treat initial stages of these neoplasms such as actinic keratoses (AK) and Bowen's disease (BD) to prevent progression to invasive and potentially fatal squamous cell carcinoma. Topical photodynamic therapy (PDT) has been proven to be an effective treatment for AK and BD in immunocompetent patients, but no prospective trials in immunocompromised TR have been performed so far.


METHODS
Twenty TR and 20 controls with histologically confirmed AK or BD underwent either a single or two consecutive treatments of topical PDT in an open trial. The application of 20% 5-aminolevulinic acid (ALA) for 5 hours was followed by illumination with 75 J/cm2 of visible light delivered at 80 mW/cm2 by an incoherent light source.


RESULTS
The overall complete response rates in TR at 4, 12, and 48 weeks were 0.86, 0.68, and 0.48, respectively. The cure rates in both patient groups were comparable at 4 weeks but were significantly lower in TR than in controls at 12 and 48 weeks (P<0.05). Side effects included erythema, edema, and crust formation after illumination. Cosmetic results were excellent without scar formation or alterations in pigmentation.


CONCLUSIONS
Topical PDT with 20% 5-ALA is an effective and safe treatment for AK and BD in immunosuppressed TR, with initial response rates comparable with those in immunocompetent patients. It is particularly useful in TR because of the possibility for repeated treatment of large lesional areas.
Dragieva
Galya
G
Department of Dermatology, University Hospital of Zurich, Zurich, Switzerland.
Hafner
Jürg
J
Dummer
Reinhard
R
Schmid-Grendelmeier
Peter
P
Roos
Malgorzata
M
Prinz
Bettina M
BM
Burg
Günter
G
Binswanger
Ulrich
U
Kempf
Werner
W
D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D001913:Bowen's Disease / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007642:Keratosis / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy; D010787:Photosensitivity Disorders / Q000150:complications*; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D011446:Prospective Studies; D013472:Sunlight / Q000009:adverse effects; D014180:Transplantation / Q000009:adverse effects*; D016896:Treatment Outcome
D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid