Journal article
Photodynamic therapy of squamous cell carcinoma. An evaluation of a new photosensitizing agent, benzoporphyrin derivative and new photoimmunoconjugate
Surgical oncology, Vol.2(3), pp.187-196
1993
DOI: 10.1016/0960-7404(93)90006-K
PMID: 8252208
Abstract
Photodynamic therapy for cancer depends on the relatively selective distribution of photosensitizing agents to malignant as compared with normal tissues, rendering the malignant cells more susceptible to light-mediated damage. Photodynamic therapy has been used with only moderate success to date. The purpose of this study was to compare a new photosensitizing agent, benzoporphyrin derivative (BPD), to the standard agent presently in use, photofrin II, in a hamster cheek pouch model of squamous cell carcinoma. As well we have investigated the potential of using a tumour-specific monoclonal antibody-BPD conjugate to improve the tumour localizing properties of BPD. Treatment consisted of photodynamic therapy with either photofrin II, BPD, or a tumour-specific anti-epidermal growth factor receptor-BPD conjugate. Control groups of light alone, anti-EGFr, tumour non-specific MoAb, and tumour nonspecific MoAb-BPD conjugate were included with the contralateral cheek pouch of each animal acting as a dark control. An assessment of differential delivery of BPD to tumour and to normal mucosa was undertaken using a spectrophotometric assay. Parametric statistical analysis included Student's
t-tests and linear regression while non-parametric analysis was undertaken using Fisher's exact test. Animals receiving BPD alone demonstrated tumour-to-tissue levels of approximately 2:1 while animals receiving the tumour-specific anti-EGFr-BPD conjugate had significantly better tumour:tissue ratios of 26:1 (
P < 0.005). Animals treated with photofrin II had a 1 month cancer-free survival of 27% while animals treated with BPD had an improved survival of 67% (
P = 0.03) The group treated with the tumour-specific anti-EGFr-BPD conjugate at a twentieth the total dose of BPD had an 80% 1 month cancer-free survival which was not statistically different from the group treated with BPD alone. Benzoporphyrin appears to be a more effective photosensitizing agent than Photofrin II and its tumour selectivity can be improved using a tumour specific monoclonal antibody conjugate.
Details
- Title: Subtitle
- Photodynamic therapy of squamous cell carcinoma. An evaluation of a new photosensitizing agent, benzoporphyrin derivative and new photoimmunoconjugate
- Creators
- A.W. Hemming - University of British ColumbiaN.L. Davis - University of British ColumbiaB. Dubois - University of British ColumbiaN.F. Quenville - University of British ColumbiaR.J. Finley - University of British Columbia
- Resource Type
- Journal article
- Publication Details
- Surgical oncology, Vol.2(3), pp.187-196
- Publisher
- Elsevier Ltd
- DOI
- 10.1016/0960-7404(93)90006-K
- PMID
- 8252208
- ISSN
- 0960-7404
- eISSN
- 1879-3320
- Language
- English
- Date published
- 1993
- Academic Unit
- Surgery
- Record Identifier
- 9984321865902771
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