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British Journal of Cancer (2000) 82, 1297–1299. doi:10.1054/bjoc.1999.1094
Published online 7 March 2000

Treatment of canine oral squamous cell carcinomas with photodynamic therapy

D L McCaw1, E R Pope1, J T Payne1, M K West1, R V Tompson2 and D Tate1

  1. 1College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
  2. 2College of Engineering, University of Missouri, Columbia, MO 65211, USA

Correspondence: D L McCaw, Clydesdale Hall, 379 East Campus Drive, Columbia, MO 65211, USA.

Received 11 May 1999; Revised 8 November 1999; Accepted 11 November 1999



Eleven dogs with naturally occurring oral squamous cell carcinomas were treated with photodynamic therapy (PDT) using Photochlor (HPPH) as the photosensitizer. The largest length of the tumours measured in a two-dimensional plane ranged from 0.9 to 6.8 cm. Seven of the tumours invaded underlying bone as determined by radiograph appearance. Photochlor was injected intravenously at a dose of 0.3 mg kg–1. Forty-eight hours later the tumours were treated. Tumours with a surface to base depth of greater than 1 cm were surgically reduced to less than 1 cm. Irradiation with 665 nm light with an energy density of 100 J cm–2was administered. Eight dogs were considered cured with no tumour recurrence for at least 17 months after treatment. Local treatment of oral squamous cell carcinomas with PDT appears to give results similar to those obtained with surgical removal of large portions of the mandible or maxilla. The cosmetic results with PDT are superior to those of radical surgical removal. The new sensitizer, Photochlor, appears effective for oral squamous carcinomas with results similar to those reported for other sensitizers. © 2000 Cancer Research Campaign


photodynamic therapy; squamous cell carcinoma; canine; photochlor; HPPH



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