Photodynamic therapy for facial squamous cell carcinoma in cats using Photofrin.
BACKGROUND
Photodynamic therapy (PDT) has been shown to be an effective treatment modality for surface-oriented neoplasms of the skin, respiratory, gastrointestinal, and urogenital systems. The purpose of our study was to assess the safety and efficacy of PDT using Photofrin in the treatment of squamous cell carcinomas of feline facial skin.


METHODS
Cats with naturally occurring squamous cell carcinomas of the skin were entered into the study. PDT was delivered to the tumors using an argon-pumped dye laser 48 hours after the administration of the photosensitizer porfimer sodium (Photofrin). Following treatment, the tumors were evaluated for complete response rates and local control durations.


RESULTS
Eight tumors were staged T1a, 9 staged T1b, and 14 staged T2b. Complete response rates as well as local control durations were significantly related to stage (p < 0.0001). Complete response was achieved in 100% of the T1a tumors and 53% of the T1b tumors; the overall 1-year local control rate for all treated tumors was 62%. Clinical, hematological, and biochemical evidence of toxicity was not seen in any cat following drug administration.


CONCLUSIONS
PDT with the photosensitizer Photofrin was safe and effective in treating early stage squamous cell carcinomas of the feline skin.
Chang
C J
CJ
Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan, R.O.C.
Lai
Y L
YL
Wong
C J
CJ
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000662:veterinary*; D002371:Cat Diseases / Q000188:drug therapy*; D002415:Cats; D017323:Dihematoporphyrin Ether / Q000627:therapeutic use*; D005153:Facial Neoplasms / Q000188:drug therapy / Q000662:veterinary*; D010778:Photochemotherapy
D000970:Antineoplastic Agents; D017323:Dihematoporphyrin Ether